| a three-dimensional stereotaxic atlas of the gray short-tailed opossum (monodelphis domestica) brain. | the gray short-tailed opossum (monodelphis domestica) is a small marsupial gaining recognition as a laboratory animal in biomedical research. despite numerous studies on opossum neuroanatomy, a consistent and comprehensive neuroanatomical reference for this species is still missing. here we present the first three-dimensional, multimodal atlas of the monodelphis opossum brain. it is based on four complementary imaging modalities: high resolution ex vivo magnetic resonance images, micro-computed ... | 2017 | 29214509 |
| ontogeny of myosin isoform expression and prehensile function in the tail of the gray short-tailed opossum (monodelphis domestica). | terrestrial opossums use their semiprehensile tail for grasping nesting materials as opposed to arboreal maneuvering. we relate the development of this adaptive behavior with ontogenetic changes in myosin heavy chain (mhc) isoform expression from 21 days to adulthood.monodelphis domesticais expected to demonstrate a progressive ability to flex the distal tail up to age 7 mo, when it should exhibit routine nest construction. we hypothesize that juvenile stages (3-7 mo) will be characterized by re ... | 2017 | 28522766 |
| evolution of mammalian sensorimotor cortex: thalamic projections to parietal cortical areas in monodelphis domestica. | the current experiments build upon previous studies designed to reveal the network of parietal cortical areas present in the common mammalian ancestor. understanding this ancestral network is essential for highlighting the basic somatosensory circuitry present in all mammals, and how this basic plan was modified to generate species specific behaviors. our animal model, the short-tailed opossum (monodelphis domestica), is a south american marsupial that has been proposed to have a similar ecologi ... | 2014 | 25620915 |
| arrested development of the dorsal column following neonatal spinal cord injury in the opossum, monodelphis domestica. | developmental studies of spinal cord injury in which regrowth of axons occurs across the site of transection rarely distinguish between the recovery of motor-controlling pathways and that of ascending axons carrying sensory information. we describe the morphological changes that occur in the dorsal column (dc) of the grey short-tailed opossum, monodelphis domestica, following spinal cord injury at two early developmental ages. the spinal cords of opossums that had had their mid-thoracic spinal c ... | 2015 | 25487408 |
| modeling sunscreen-mediated melanoma prevention in the laboratory opossum (monodelphis domestica). | | 2014 | 24931873 |
| age-dependent transcriptome and proteome following transection of neonatal spinal cord of monodelphis domestica (south american grey short-tailed opossum). | this study describes a combined transcriptome and proteome analysis of monodelphis domestica response to spinal cord injury at two different postnatal ages. previously we showed that complete transection at postnatal day 7 (p7) is followed by profuse axon growth across the lesion with near-normal locomotion and swimming when adult. in contrast, at p28 there is no axon growth across the lesion, the animals exhibit weight-bearing locomotion, but cannot use hind limbs when swimming. here we examine ... | 2014 | 24914927 |
| immunohistological study of the endometrial stromal fibroblasts in the opossum, monodelphis domestica: evidence for homology with eutherian stromal fibroblasts. | molecular phylogenetic studies suggest that the hemochorial placentation and decidualization are ancestral traits of eutherian mammals. while the origin of the placental tissue is well understood, the origin of the decidual cells is unclear. here we address the origin of decidual cells by examining the expression patterns of six transcription factors (tfs) as well as four structural proteins in the endometrium of a marsupial, monodelphis domestica, and compared them with the patterns known from ... | 2014 | 24740599 |
| the unique paired retinal vessels of the gray short-tailed opossum (monodelphis domestica) and their relationship to astrocytes and microglial cells. | in marsupials that possess a retinal vasculature, the arterial and venous segments, down to the smallest calibre capillaries, have been shown to occur in pairs. this pattern is seen in the marsupial central nervous system (cns) but not in other tissues in this group or in any tissues in eutherian mammals. the present study aimed to determine if the gray short-tailed opossum (monodelphis domestica), a south american marsupial, possesses double retinal vessels. secondly, we investigated the relati ... | 2017 | 28371527 |
| a new developmental mechanism for the separation of the mammalian middle ear ossicles from the jaw. | multiple mammalian lineages independently evolved a definitive mammalian middle ear (dmme) through breakdown of meckel's cartilage (mc). however, the cellular and molecular drivers of this evolutionary transition remain unknown for most mammal groups. here, we identify such drivers in the living marsupial opossummonodelphis domestica, whose mc transformation during development anatomically mirrors the evolutionary transformation observed in fossils. specifically, we link increases in cellular ap ... | 2017 | 28179517 |
| torpor at high ambient temperature in a neotropical didelphid, the grey short-tailed opossum (monodelphis domestica). | the grey short-tailed opossum, monodelphis domestica, has been an established research animal for more than five decades, but relatively, little is known about its thermophysiology. here we studied core body temperature (t b) and metabolic rate (mr) of female adult m. domestica housed in the laboratory at an ambient temperature (t a) of 26 °c. in expanding previous reports, the average recorded core t b of m. domestica was 34.3 °c. the t b of an individual m. domestica can drop below 30 °c (mini ... | 2014 | 25142634 |
| function of pretribosphenic and tribosphenic mammalian molars inferred from 3d animation. | appearance of the tribosphenic molar in the late jurassic (160 ma) is a crucial innovation for food processing in mammalian evolution. this molar type is characterized by a protocone, a talonid basin and a two-phased chewing cycle, all of which are apomorphic. in this functional study on the teeth of late jurassic dryolestes leiriensis and the living marsupial monodelphis domestica, we demonstrate that pretribosphenic and tribosphenic molars show fundamental differences of food reduction strateg ... | 2014 | 25091547 |
| facial mechanosensory influence on forelimb movement in newborn opossums, monodelphis domestica. | the opossum, monodelphis domestica, is born very immature but crawls, unaided, with its forelimbs (fl) from the mother's birth canal to a nipple where it attaches to pursue its development. what sensory cues guide the newborn to the nipple and trigger its attachment to it? previous experiments showed that low intensity electrical stimulation of the trigeminal ganglion induces fl movement in in vitro preparations and that trigeminal innervation of the facial skin is well developed in the newborn. ... | 2016 | 26848758 |
| genome-wide histone state profiling of fibroblasts from the opossum, monodelphis domestica, identifies the first marsupial-specific imprinted gene. | imprinted genes have been extensively documented in eutherian mammals and found to exhibit significant interspecific variation in the suites of genes that are imprinted and in their regulation between tissues and developmental stages. much less is known about imprinted loci in metatherian (marsupial) mammals, wherein studies have been limited to a small number of genes previously known to be imprinted in eutherians. we describe the first ab initio search for imprinted marsupial genes, in fibrobl ... | 2014 | 24484454 |
| complete mitochondrial genome of tlacuatzin canescens (grayish mouse opossum). | in this study, we report the complete mitochondrial genome of the grayish mouse opossumm, tlacuatzin canescens. the mitochondrial genome is 16 460 bp in length and has a base composition of a (35.7%), t (31.3%), c (21.3%), and g (11.7%), demonstrating an obvious bias of high at content (67%). the mitochondrial genome contains a typically conserved structure, encoding 13 protein-coding genes (pcgs), 20 transfer rna genes (trna), 2 ribosomal rna genes (12s rrna and 16s rrna), and a control region ... | 2017 | 26714099 |
| correlation between dopaminergic phenotype and expression of calretinin in the midbrain nuclei of the opossum (monodelphis domestica): an immunohistological study. | we investigated distribution and morphology of neurons of the midbrain nuclei: the ventral tegmental area (vta), substantia nigra (sn) and periaqueductal gray (pag) of the adult grey short-tailed opossums that were double immunolabeled for the presence of calretinin (cr) and/or tyrosine hydroxylase (th). the majority of th-immunopositive neurons and fibers were located in the vta, sn, and only scarce population of small neurons expressing th was present in the pag. in the sn 80 percent of th-exp ... | 2013 | 24457643 |
| distribution and function of trkb receptors in the developing brain of the opossum monodelphis domestica. | the expression, development pattern, spatiotemporal distribution, and function of trkb receptors were investigated during the postnatal brain development of the opossum. full-length trkb receptor expression was detectable in the newborn opossum, whereas three different short forms that are expressed in the adult brain were almost undetectable in the newborn opossum brain. the highest level of full-length trkb receptor expression was observed at p35, which corresponds to the time of eye opening. ... | 2014 | 24443161 |
| the cellular composition of the marsupial neocortex. | in the current investigation we examined the number and proportion of neuronal and non-neuronal cells in the primary sensory areas of the neocortex of a south american marsupial, the short-tailed opossum (monodelphis domestica). the primary somatosensory (s1), auditory (a1), and visual (v1) areas were dissected from the cortical sheet and compared with each other and the remaining neocortex using the isotropic fractionator technique. we found that although the overall sizes of v1, s1, a1, and th ... | 2014 | 24414857 |
| a new mammalian model system for thalidomide teratogenesis: monodelphis domestica. | from 1957 to 1962, thalidomide caused birth defects in >10,000 children. while the drug was pulled from the market, thalidomide is currently prescribed to treat conditions including leprosy. as a result, a new generation of babies with thalidomide defects is being born in the developing world. this represents a serious problem, as the mechanisms by which thalidomide disrupts development remain unresolved. this lack of resolution is due, in part, to the absence of an appropriate mammalian model f ... | 2017 | 28130151 |
| on the prenatal initiation of t cell development in the opossum monodelphis domestica. | thymus-dependent lymphocytes (t cells) are a critical cell lineage in the adaptive immune system of all jawed vertebrates. in eutherian mammals the initiation of t cell development takes place prenatally and the offspring of many species are born relatively immuno-competent. marsupials, in contrast, are born in a comparatively altricial state and with a less well developed immune system. as such, marsupials are valuable models for studying the peri- and postnatal initiation of immune system deve ... | 2017 | 28052333 |
| cortical plasticity following stripe rearing in the marsupial monodelphis domestica: neural response properties of v1. | the functional organization of the primary visual area (v1) and the importance of sensory experience in its normal development have been well documented in eutherian mammals. however, very few studies have investigated the response properties of v1 neurons in another large class of mammals, or whether sensory experience plays a role in shaping their response properties. thus we reared opossums (monodelphis domestica) in normal and vertically striped cages until they reached adulthood. they were ... | 2017 | 27852732 |
| the ut family of mhc class i loci unique to non-eutherian mammals has limited polymorphism and tissue specific patterns of expression in the opossum. | the major histocompatibility complex (mhc) class i family of genes encode for molecules that have well-conserved structures, but have evolved to perform diverse functions. the availability of the gray, short-tailed opossum, monodelphis domestica whole genome sequence has allowed for analysis of mhc class i gene content in this marsupial. utilization of a novel method to search for mhc related domain structures revealed a previously unknown family of mhc class i-related genes. these genes, named ... | 2016 | 27825298 |
| convergent and divergent evolution of genomic imprinting in the marsupial monodelphis domestica. | genomic imprinting is an epigenetic phenomenon resulting in parent-of-origin specific monoallelic gene expression. it is postulated to have evolved in placental mammals to modulate intrauterine resource allocation to the offspring. in this study, we determined the imprint status of metatherian orthologues of eutherian imprinted genes. | 2012 | 22899817 |
| conserved and divergent expression patterns of markers of axial development in the laboratory opossum, monodelphis domestica. | previous comparative studies suggest that the requirement for nodal in epiblast and hypoblast development is unique to mammalians. expression of anterior visceral endoderm (ave) genes in the visceral endoderm and of their orthologs in the hypoblast may be unique to mammalians and avians, and is absent in the reptilian hypoblast. axis formation in reptiles is signaled by the formation of the posterior marginal epiblast (pme), which expresses a series of primitive streak genes. to assess the phylo ... | 2016 | 27666927 |
| functional conservation of the lncrna neat1 in the ancestrally diverged marsupial lineage: evidence for neat1 expression and associated paraspeckle assembly during late gestation in the opossum monodelphis domestica. | long non-coding rnas (lncrnas) are widely expressed and play various roles in cell homeostasis. however, because of their low conservation at the sequence level, recapitulating lncrna evolutionary history is often challenging. while performing an ultrastructural analysis of viral particles present in uterine glands of gestating opossum females, we serendipitously noticed the presence of numerous structures similar to paraspeckles, nuclear bodies which in human and mouse cells are assembled aroun ... | 2016 | 27315396 |
| body size and the small branch niche: using marsupial ontogeny to model primate locomotor evolution. | recently proposed ancestral locomotor and morphological 'stages' leading to the evolution of primates have emphasized small body size, and a transition from a clawed non-grasping stage, to a clawed, grasping stage with clawless opposable hallux, to a fully-nailed primate with grasping extremities. this evolutionary transition was presumably associated with frequent use of the small branch niche. to model elements of these evolutionary transitions, we investigate how body size, substrate size, su ... | 2014 | 24508352 |
| cellular basis of differential limb growth in postnatal gray short-tailed opossums (monodelphis domestica). | while growth has been studied extensively in invertebrates, the mechanisms by which it is controlled in vertebrates, particularly in mammals, remain poorly understood. in this study, we investigate the cellular basis of differential limb growth in postnatal monodelphis domestica, the gray short-tailed opossum, to gain insights into the mechanisms regulating mammalian growth. opossums are an ideal model for the study of growth because they are born with relatively large, well-developed forelimbs ... | 2014 | 24500902 |
| cellular and molecular drivers of differential organ growth: insights from the limbs of monodelphis domestica. | a fundamental question in biology is "how is growth differentially regulated during development to produce organs of particular sizes?" we used a new model system for the study of differential organ growth, the limbs of the opossum (monodelphis domestica), to investigate the cellular and molecular basis of differential organ growth in mammals. opossum forelimbs grow much faster than hindlimbs, making opossum limbs an exceptional system with which to study differential growth. we first used the g ... | 2016 | 27194412 |
| asp-ase activity of the opossum granzyme b supports the role of granzyme b as part of anti-viral immunity already during early mammalian evolution. | granzyme b is one of the key effector molecules in our defense against viruses and intracellular bacteria. this serine protease together with the pore forming protein perforin, induces caspase or bid-dependent apoptosis in target cells. here we present the first characterization of a granzyme b homolog, the grathepsodenase, in a non-placental mammal, the american opossum (monodelphis domestica). the recombinant enzyme was produced in a human cell line and used to study its primary and extended c ... | 2016 | 27152961 |
| the evolution of whisker-mediated somatosensation in mammals: sensory processing in barrelless s1 cortex of a marsupial, monodelphis domestica. | movable tactile sensors in the form of whiskers are present in most mammals, but sensory coding in the cortical whisker representation has been studied almost exclusively in mice and rats. many species that possess whiskers lack the modular "barrel" organization found in the primary somatosensory cortex (s1) of mice and rats, but it is unclear how whisker-related input is represented in these species. we used single-unit extracellular recording techniques to characterize receptive fields and res ... | 2016 | 27098555 |
| the cytoskeletal system of mammalian primitive erythrocytes: studies in developing marsupials. | seeking to resolve conflicting literature on cytoskeletal structure in mammalian "primitive" generation erythrocytes, we have utilized the circulating blood of developing marsupials. in young of the tammar wallaby (macropus eugenii) and the gray short-tailed opossum (monodelphis domestica), relatively large, nucleated primitive erythrocytes constituted nearly 100% of the circulating population at birth (= day 0) and in fetuses (tammar) several days before birth. these cells were discoidal or ell ... | 1990 | 2376068 |
| spermiogenesis and spermiation in a marsupial, the tammar wallaby (macropus eugenii). | fourteen steps of spermatid development in the tammar wallaby (macropus eugenii), from the newly formed spermatid to the release of the spermatozoon into the lumen of the seminiferous tubules, were recognised at the ultrastructural level using transmission and scanning electron microscopy. this study confirmed that although the main events are generally similar, the process of the differentiation of the spermatid in marsupials is notably different and relatively more complex than that in most st ... | 1997 | 9147224 |
| cranial osteogenesis in monodelphis domestica (didelphidae) and macropus eugenii (macropodidae). | the pattern of onset and general rate of cranial ossification are compared in two marsupials, monodelphis domestica (didelphidae) and macropus eugenii (macropodidae). in both species a similar suite of bones is present at birth, specifically those surrounding the oral cavity and the exoccipital, and in both postnatal events follow a similar course. the facial skeleton matures more rapidly than the neurocranium, which is characterized by an extended period of ossification. most dermal bones begin ... | 1993 | 8445660 |
| the evolution of active vibrissal sensing in mammals: evidence from vibrissal musculature and function in the marsupial opossum monodelphis domestica. | facial vibrissae, or whiskers, are found in nearly all extant mammal species and are likely to have been present in early mammalian ancestors. a sub-set of modern mammals, including many rodents, move their long mystacial whiskers back and forth at high speed whilst exploring in a behaviour known as 'whisking'. it is not known whether the vibrissae of early mammals moved in this way. the grey short-tailed opossum, monodelphis domestica, is considered a useful species from the perspective of trac ... | 2013 | 23737559 |
| immunolocalization of cation-chloride cotransporters in the developing and mature spinal cord of opossums, monodelphis domestica. | spinal inhibition is required to generate coordinated outputs between antagonistic muscles during locomotion. it relies on low neuronal chloride concentration set by two cation-chloride cotransporters, nkcc1 and kcc2 which, respectively, pumps cl(-) in or out of neurons. it is generally accepted that nkcc1 is gradually inactivated during development, while kcc2 is upregulated and activated, resulting in low intracellular [cl(-)]. newborn opossums are very immature but perform rhythmic and altern ... | 2013 | 23720613 |
| expression and cellular distribution of ubiquitin in response to injury in the developing spinal cord of monodelphis domestica. | ubiquitin, an 8.5 kda protein associated with the proteasome degradation pathway has been recently identified as differentially expressed in segment of cord caudal to site of injury in developing spinal cord. here we describe ubiquitin expression and cellular distribution in spinal cord up to postnatal day p35 in control opossums (monodelphis domestica) and in response to complete spinal transection (t10) at p7, when axonal growth through site of injury occurs, and p28 when this is no longer pos ... | 2013 | 23626776 |
| expression patterns of oct4, cdx2, tead4, and yap1 proteins during blastocyst formation in embryos of the marsupial, monodelphis domestica wagner. | the marsupial blastocyst forms in an entirely different manner from its eutherian counterpart, involving cell-zona rather than cell-cell adhesion during the 8- to-16-cell transition. while the eutherian blastocyst consists of a spherical trophoblast completely enveloping a pluripotent inner cell mass, or pluriblast, the marsupial blastocyst forms initially as a bowl-shaped monolayer of cells lining the zona pellucida at the embryonic pole (ep). this monolayer contains a small patch of centrally ... | 2013 | 23607301 |
| marsupials and monotremes possess a novel family of mhc class i genes that is lost from the eutherian lineage. | major histocompatibility complex (mhc) class i genes are found in the genomes of all jawed vertebrates. the evolution of this gene family is closely tied to the evolution of the vertebrate genome. family members are frequently found in four paralogous regions, which were formed in two rounds of genome duplication in the early vertebrates, but in some species class is have been subject to additional duplication or translocation, creating additional clusters. the gene family is traditionally group ... | 2015 | 26194104 |
| amelotin gene structure and expression during enamel formation in the opossum monodelphis domestica. | amelotin (amtn) is an ameloblast-secreted protein that belongs to the secretory calcium-binding phosphoprotein family, which also includes the enamel matrix proteins amelogenin, ameloblastin and enamelin. although amtn is supposed to play an important role in enamel formation, data were long limited to the rodents, in which it is expressed during the maturation stage. recent comparative studies in sauropsids and amphibians revealed that (i) amtn was expressed earlier, i.e. as soon as ameloblasts ... | 2015 | 26186457 |
| genomic identification of chemokines and cytokines in opossum. | the cytokine repertoire of marsupials is largely unknown. the sequencing of the opossum genome has expedited the identification of many immune genes. however, many genes have not been identified using automated annotation pipelines because of high levels of sequence divergence. to fill gaps in our knowledge of the cytokine gene complement in marsupials, we searched the genome assembly of the gray short-tailed opossum for chemokine, interleukin, colony-stimulating factor, tumor necrosis factor, a ... | 2011 | 21214366 |
| ultrastructural analysis between fetal and adult wound healing process of marsupial opossum skin. | the opossum delivers a newborn baby equivalent to tremature fetus state by postpregnancy. the peculiarity is advantageous for studies of fetus, because operations to take out fetus from the uterus of a mother are not necessary. when mammalian skin is wounded by full-thickness excision, fetal and adult wound healing processes differ. fetal-type wound healing does not leave a scar. however, studies of how the fetal wound healing process differs in detail from the adult type are not advanced. we fi ... | 2015 | 25912322 |
| forelimb preferences in quadrupedal marsupials and their implications for laterality evolution in mammals. | acquisition of upright posture in evolution has been argued to facilitate manual laterality in primates. owing to the high variety of postural habits marsupials can serve as a suitable model to test whether the species-typical body posture shapes forelimb preferences in non-primates or this phenomenon emerged only in the course of primate evolution. in the present study we aimed to explore manual laterality in marsupial quadrupeds and compare them with the results in the previously studied biped ... | 2013 | 23497116 |
| differential changes in the cellular composition of the developing marsupial brain. | throughout development both the body and the brain change at remarkable rates. specifically, the number of cells in the brain undergoes dramatic nonlinear changes, first exponentially increasing in cell number and then decreasing in cell number. different cell types, such as neurons and glia, undergo these changes at different stages of development. the current investigation used the isotropic fractionator method to examine the changes in cellular composition at multiple developmental milestones ... | 2013 | 23322491 |
| chromosome-wide profiling of x-chromosome inactivation and epigenetic states in fetal brain and placenta of the opossum, monodelphis domestica. | evidence from a few genes in diverse species suggests that x-chromosome inactivation (xci) in marsupials is characterized by exclusive, but leaky inactivation of the paternally derived x chromosome. to study the phenomenon of marsupial xci more comprehensively, we profiled parent-of-origin allele-specific expression, dna methylation, and histone modifications in fetal brain and extra-embryonic membranes in the gray, short-tailed opossum (monodelphis domestica). the majority of x-linked genes (15 ... | 2014 | 24065774 |
| cephalic sensory influence on forelimb movement in newborn opossums, monodelphis domestica. | like other marsupials, the opossum monodelphis domestica is born very immature and crawls, unaided by the mother, from the urogenital opening to a nipple where it attaches and pursues its development. if the alternate, rhythmic movements of the forelimbs which allow this locomotion are generated by the developing spinal motor networks, sensory information is nonetheless needed to guide the newborn to a nipple. behavioral, anatomical and physiological studies suggest that the auditory and the vis ... | 2013 | 23103914 |
| early postnatal b cell ontogeny and antibody repertoire maturation in the opossum, monodelphis domestica. | marsupials are a lineage of mammals noted for giving birth to highly altricial young, which complete much of their "fetal" development externally attached to a teat. postnatal b cell ontogeny and diversity was investigated in a model marsupial species, the gray short-tailed opossum, monodelphis domestica. the results support the initiation of b cell development late in gestation and progressing into the first two weeks of postnatal life. transcription of cd79a and cd79b was detected in embryonic ... | 2012 | 23029324 |
| heterochrony in somitogenesis rate in a model marsupial, monodelphis domestica. | marsupial newborns are highly altricial and also show a wide array of shifts in the rate or timing of developmental events so that certain neonatal structures are quite mature. one particularly notable feature is the steep gradient in development along the anterior-posterior axis such that anterior structures are generally well developed relative to posterior ones. here, we study somitogenesis in the marsupial, monodelphis domestica, and document two heterochronies that may be important in gener ... | 2012 | 23016977 |
| visual acuity in the short-tailed opossum (monodelphis domestica). | monodelphis domestica (short-tailed opossum) is an emerging animal model for studies of neural development due to the extremely immature state of the nervous system at birth and its subsequent rapid growth to adulthood. yet little is known about its normal sensory discrimination abilities. in the present investigation, visual acuity was determined in this species using the optokinetic test (opt), which relies on involuntary head tracking of a moving stimulus and can be easily elicited using a ro ... | 2012 | 22871523 |
| disparate igf1 expression and growth in the fore- and hind limbs of a marsupial mammal (monodelphis domestica). | proper regulation of growth is essential to all stages of life, from development of the egg into an embryo to the maintenance of normal cell cycle progression in adults. however, despite growth's importance to basic biology and health, little is known about how mammalian growth is regulated. in this study, we investigated the molecular basis of the highly disparate growth of opossum fore- and hind limbs in utero. we first used a novel, opossum-specific microarray to identify several growth-relat ... | 2012 | 22821864 |
| response to novelty in the laboratory wistar rat, wild-captive wwcps rat, and the gray short-tailed opossum (monodelphis domestica). | behavior of the laboratory gray short-tailed opossums (monodelphis domestica), warsaw wild captive pisula stryjek rats (wwcps) and laboratory rats (wistar) has been registered in the period of familiarization with a new environment and consecutive confrontation with a novel, innocuous object placed in that familiarized environment. in the new environment the sequence of anxiety, investigation, and habituation was shortest in the opossum, longer in the laboratory rat and longest in the wwcps rat. ... | 2012 | 22776746 |
| the opossum mhc genomic region revisited. | the gray short-tailed opossum monodelphis domestica is one of the few marsupial species for which a high quality whole genome sequence is available and the major histocompatibility complex (mhc) region has been annotated. previous analyses revealed only a single locus within the opossum mhc region, designated modo-ua1, with the features expected for encoding a functionally classical class i α-chain. nine other class i genes found within the mhc are highly divergent and have features usually asso ... | 2015 | 25737310 |
| exogenous retinoic acid induces digit reduction in opossums (monodelphis domestica) by disrupting cell death and proliferation, and apical ectodermal ridge and zone of polarizing activity function. | retinoic acid (ra) is a vitamin a derivative. exposure to exogenous ra generates congenital limb malformations (clms) in species from frogs to humans. these clms include but are not limited to oligodactyly and long-bone hypoplasia. the processes by which exogenous ra induces clms in mammals have been best studied in mouse, but as of yet remain unresolved. | 2015 | 25656823 |
| rsx is a metatherian rna with xist-like properties in x-chromosome inactivation. | in female (xx) mammals, one of the two x chromosomes is inactivated to ensure an equal dose of x-linked genes with males (xy). x-chromosome inactivation in eutherian mammals is mediated by the non-coding rna xist. xist is not found in metatherians (marsupials), and how x-chromosome inactivation is initiated in these mammals has been the subject of speculation for decades. using the marsupial monodelphis domestica, here we identify rsx (rna-on-the-silent x), an rna that has properties consistent ... | 2012 | 22722828 |
| horizontal spinning of transposons. | the term 'horizontal transfer (ht)' refers to the transfer of genetic material between two reproductively isolated organisms. ht is thought to occur rarely in eukaryotes compared to vertical inheritance, the transmission of dna from parent to offspring. in a recent study we have provided evidence that a family of dna transposons, called space invaders or spin, independently invaded horizontally the genome of seven distantly related tetrapod species and subsequently amplified to high copy number ... | 2009 | 19704906 |
| recombination, transcription, and diversity of a partially germline-joined vh in a mammal. | full or partially germline-joined v genes have been described in a number of different vertebrate lineages where they can contribute to the expressed antibody repertoire through different mechanisms. here we demonstrate that vh3.1, a partially germline-joined vh gene in the opossum monodelphis domestica, can undergo v(d)j recombination to generate productive igh transcripts. vh3.1 is fused to a dh gene segment in the germline dna and is the only known example of a germline-joined vh in a mammal. ... | 2012 | 22710822 |
| weight-bearing locomotion in the developing opossum, monodelphis domestica following spinal transection: remodeling of neuronal circuits caudal to lesion. | complete spinal transection in the mature nervous system is typically followed by minimal axonal repair, extensive motor paralysis and loss of sensory functions caudal to the injury. in contrast, the immature nervous system has greater capacity for repair, a phenomenon sometimes called the infant lesion effect. this study investigates spinal injuries early in development using the marsupial opossum monodelphis domestica whose young are born very immature, allowing access to developmental stages ... | 2013 | 23951105 |
| marsupial-specific micrornas evolved from marsupial-specific transposable elements. | using a direct mirna cloning strategy we previously identified fourteen marsupial- or species-specific micrornas in the marsupial species monodelphis domestica. in the present study we examined each of the pre-mirnas and their flanking sequences and demonstrate that half of these mirnas evolved from marsupial-specific transposable elements. these findings reinforce the view that transposable elements are a previously unappreciated source of new, lineage-specific micrornas. | 2009 | 19577616 |
| a connection to the past: monodelphis domestica provides insight into the organization and connectivity of the brains of early mammals. | the current experiment is one of a series of comparative studies in our laboratory designed to determine the network of somatosensory areas that are present in the neocortex of the mammalian common ancestor. such knowledge is critical for appreciating the basic functional circuitry that all mammals possess and how this circuitry was modified to generate species-specific, sensory-mediated behavior. our animal model, the gray short-tailed opossum (monodelphis domestica), is a marsupial that is pro ... | 2013 | 23784751 |
| a vpreb3 homologue in a marsupial, the gray short-tailed opossum, monodelphis domestica. | a vpreb surrogate light (sl) chain was identified for the first time in a marsupial, the opossum monodelphis domestica. comparing the opossum vpreb to homologues from eutherian (placental mammals) and avian species supported the marsupial gene being vpreb3. vpreb3 is a protein that is not known to traffic to the cell surface as part of the pre-b cell receptor. rather, vpreb3 associates with nascent immunoglobulin chains in the endoplasmic reticulum. homologues of other known sl chains vpreb1, vp ... | 2012 | 22684248 |
| shape, variance and integration during craniogenesis: contrasting marsupial and placental mammals. | studies of morphological integration can provide insight into developmental patterns, even in extinct taxa known only from skeletal remains, thus making them an important tool for studies of evolutionary development. however, interpreting patterns of integration and assessing their significance for organismal evolution requires detailed understanding of the developmental interactions that shape integration and how those interactions change through ontogeny. thus far, relatively little comparativ ... | 2012 | 22356604 |
| age-dependent changes in the proteome following complete spinal cord transection in a postnatal south american opossum (monodelphis domestica). | recovery from severe spinal injury in adults is limited, compared to immature animals who demonstrate some capacity for repair. using laboratory opossums (monodelphis domestica), the aim was to compare proteomic responses to injury at two ages: one when there is axonal growth across the lesion and substantial behavioural recovery and one when no axonal growth occurs. anaesthetized pups at postnatal day (p) 7 or p28 were subjected to complete transection of the spinal cord at thoracic level t10. ... | 2011 | 22110655 |
| spontaneous development of full weight-supported stepping after complete spinal cord transection in the neonatal opossum, monodelphis domestica. | spinal cord trauma in the adult nervous system usually results in permanent loss of function below the injury level. the immature spinal cord has greater capacity for repair and can develop considerable functionality by adulthood. this study used the marsupial laboratory opossum monodelphis domestica, which is born at a very early stage of neural development. complete spinal cord transection was made in the lower-thoracic region of pups at postnatal-day 7 (p7) or p28, and the animals grew to adu ... | 2011 | 22073202 |
| microscopic anatomy of the lower respiratory tract of the grey short-tailed opossum (monodelphis domestica). | the respiratory tracts of seven grey short-tailed opossums were histologically examined. six opossums were prepared by perfusion with buffered formalin. opossum seven was perfused with gluteraldehyde. samples taken from the respiratory passages and lungs of specimens 1-6 were stained with haematoxylin and eosin. a mixture of methylene and azure blue was used for specimen 7. the trachea and right and left principal bronchi are lined with a pseudostratified ciliated columnar epithelium with occasi ... | 2012 | 21919952 |
| lung development of monotremes: evidence for the mammalian morphotype. | the reproductive strategies and the extent of development of neonates differ markedly between the three extant mammalian groups: the monotremata, marsupialia, and eutheria. monotremes and marsupials produce highly altricial offspring whereas the neonates of eutherian mammals range from altricial to precocial. the ability of the newborn mammal to leave the environment in which it developed depends highly on the degree of maturation of the cardio-respiratory system at the time of birth. the lung s ... | 2009 | 19051249 |
| progesterone receptor in the forebrain of female gray short-tailed opossums: effects of exposure to male stimuli. | progesterone receptor immunoreactivity (prir) in brain areas involved in reproductive behavior in eutherian species was examined for the first time in a female marsupial, the gray short-tailed opossum (monodelphis domestica, hereinafter, opossum). prir in nuclei of neurons, measured as area covered by stained nuclei, was seen in the arcuate nucleus (arc); anteroventral periventricular nucleus (avpv); bed nucleus of the stria terminalis (bst); medial preoptic area (mpoa), and ventromedial hypotha ... | 2009 | 19000689 |
| sparc/osteonectin, an endogenous mechanism for targeting albumin to the blood-cerebrospinal fluid interface during brain development. | specialized populations of choroid plexus epithelial cells have previously been shown to be responsible for the transfer of individual plasma proteins from blood to the cerebrospinal fluid (csf), contributing to their characteristically high concentrations in csf of the developing brain. the mechanism of this protein transfer remains elusive. using a marsupial, monodelphis domestica, we demonstrate that the albumin-binding protein sparc (osteonectin/bm-40/culture-shock protein) is present in a s ... | 2011 | 21899600 |
| an x chromosome microrna cluster in the marsupial species monodelphis domestica. | micrornas (mirnas) are an important class of posttranscriptional gene expression regulators. in the course of mapping novel marsupial-specific mirnas in the genome of the gray short-tailed opossum, monodelphis domestica, we encountered a cluster of 39 actual and potential mirnas spanning 102 kb of the x chromosome. analysis of the cluster revealed that 37 of the 39 mirnas are predicted to form thermodynamically stable hairpins, and at least 3 members have been directly cloned from m. domestica t ... | 2017 | 21685406 |
| histone h3 trimethylation at lysine 9 marks the inactive metaphase x chromosome in the marsupial monodelphis domestica. | in somatic cells of female marsupial and eutherian mammals, x chromosome inactivation (xci) occurs. xci results in the transcriptional silencing of one of the two x chromosomes and is accompanied by specific covalent histone modifications attributable to the inactive chromatin state. because data about repressed chromatin of the inactive x chromosome (xi) in marsupials are sparse, we examined in more detail the distribution of active and inactive chromatin markers on metaphase x chromosomes of a ... | 2011 | 21110203 |
| development of the lateral ventricular choroid plexus in a marsupial, monodelphis domestica. | choroid plexus epithelial cells are the site of blood/cerebrospinal fluid (csf) barrier and regulate molecular transfer between the two compartments. their mitotic activity in the adult is low. during development, the pattern of growth and timing of acquisition of functional properties of plexus epithelium are not known. | 2010 | 20920364 |
| chemical communication and reproduction in the gray short-tailed opossum (monodelphis domestica). | the gray short-tailed opossum is one of the most widely studied of all marsupials and an important model for study of olfactory communication, particularly as it relates to pheromonal activation of reproduction. males respond to differentially to female skin gland secretions and urine from anestrous females, while females respond only skin gland secretions, particularly that of the suprasternal gland. divergent responses by male and female opossums to odors from these different body sources are ... | 2010 | 20831955 |
| ontogenetic variation in the bony labyrinth of monodelphis domestica (mammalia: marsupialia) following ossification of the inner ear cavities. | ontogeny, or the development of an individual from conception to death, is a major source of variation in vertebrate morphology. all anatomical systems are affected by ontogeny, and knowledge of the ontogenetic history of these systems is important to understand when formulating biological interpretations of evolutionary history and physiology. the present study is focused on how variation affects the bony labyrinth across a growth series of an extant mammal after ossification of the inner ear c ... | 2010 | 20730862 |
| differential expression of intestinal genes in opossums with high and low responses to dietary cholesterol. | high and low responding opossums (monodelphis domestica) differ in their plasma very low density lipoprotein and low density lipoprotein (vldl+ldl) cholesterol concentrations when they consume a high cholesterol diet, which is due in part to absorption of a higher percentage of dietary cholesterol in high responders. we compared the expression of a set of genes that influence cholesterol absorption in high and low responders fed a basal or a high cholesterol and low fat (hclf) diet. up-regulatio ... | 2010 | 20721351 |
| the divergent development of the apical ectodermal ridge in the marsupial monodelphis domestica. | marsupials give birth after short gestation times to neonates that have an intriguing combination of precocial and altricial features, based on their functional necessity after birth. perhaps most noticeably, marsupial newborns have highly developed forelimbs, which provide the propulsion necessary for the newborn's crawl to the teat. to achieve their advanced state at birth, the development of marsupial forelimbs is accelerated. the development of the newborn's hind limb, which plays no part in ... | 2010 | 20665811 |
| localization of genes for v+ldl plasma cholesterol levels on two diets in the opossum monodelphis domestica. | plasma cholesterol levels among individuals vary considerably in response to diet. however, the genes that influence this response are largely unknown. non-hdl (v+ldl) cholesterol levels vary dramatically among gray, short-tailed opossums fed an atherogenic diet, and we previously reported that two quantitative trait loci (qtls) influenced v+ldl cholesterol on two diets. we used hypothesis-free, genome-wide linkage analyses on data from 325 pedigreed opossums and located one qtl for v+ldl choles ... | 2010 | 20650928 |
| husbandry of monodelphis domestica in the study of mammalian embryogenesis. | monodelphis domestica, commonly called the laboratory opossum, is a useful laboratory animal for studying marsupial embryogenesis and mammalian development. females breed year-round and the animals can be sustainably bred indoors. the authors draw on their own laboratory's experience to supplement previously published research on laboratory opossums. they describe a breeding protocol that reliably produces timed-pregnant m. domestica. additionally, the authors discuss general laboratory opossum ... | 2010 | 20567232 |
| perinatal exposure to progesterone, estradiol, or mifepristone affects sexual differentiation of behavior in opossums (monodelphis domestica). | the effects of perinatal exposure to progesterone (p) and estradiol (e) on sexual differentiation of behavior and morphology were examined by treating male and female gray short-tailed opossums on postnatal day 8 with progesterone alone (p), p plus estradiol (e) (pe), the p receptor antagonist mifepristone/ru486 (mif), or corn oil control (c) and gonadectomizing them before puberty. when given female hormone replacement therapy in adulthood and tested with intact stimulus males, mif animals show ... | 2010 | 20362579 |
| the developmental reduction of the marsupial coracoid: a case study in monodelphis domestica. | during their embryogenesis, marsupials develop a unique structure, the shoulder arch, which provides the structural and muscle-attachment support necessary for the newborn's crawl to the teat. one of the most pronounced and important aspects of the shoulder arch is an enlarged coracoid. after marsupial newborns reach the teat, the shoulder arch is remodeled and the coracoid is reduced to a small process on the scapula. although an understanding of marsupial coracoid reduction has the potential t ... | 2010 | 20151407 |
| distribution of the neuronal gap junction protein connexin36 in the spinal cord enlargements of developing and adult opossums, monodelphis domestica. | we use opossums monodelphis domestica to study the development of mammalian motor systems. the immature forelimbs of the newborn perform rhythmic and alternating movements that are likely under spinal control. the hindlimbs start moving in the second week. chemical synapses are scant in the spinal enlargements of neonatal opossums and the presence of electrochemical synapses has not been evaluated in this species or in other marsupials. as a first step aiming at evaluating the existence of such ... | 2010 | 20134154 |
| necrosis of the pinnae in a grey short-tailed opossum (monodelphis domestica). | | 2010 | 20097895 |
| american marsupials chromosomes: why study them? | marsupials, one of the three main groups of mammals, are only found in australia and in the american continent. studies performed in australian marsupials have demonstrated the great potential provided by the group for the understanding of basic genetic mechanisms and chromosome evolution in mammals. genetic studies in american marsupials are relatively scarce and cytogenetic data of most species are restricted to karyotype descriptions, usually without banding patterns. nevertheless, the first ... | 2009 | 21637437 |
| the effects of substrate texture on the mechanics of quadrupedal arboreal locomotion in the gray short-tailed opossum (monodelphis domestica). | among small mammals, the ability to move on tree trunks, branches, and twigs is nearly ubiquitous. performance and locomotor mechanics on arboreal substrates may be influenced by variation in the coefficient of friction between the hands/feet of the animal and the surface of the arboreal substrate. to test this, i examined speed, substrate reaction forces, and torque around the long axis of two cylindrical trackways with rough and smooth surfaces in gray short-tailed opossums (monodelphis domest ... | 2009 | 19691059 |
| reduction of the number of new cells reaching olfactory bulbs impairs olfactory perception in the adult opossum. | in adult mammals cells generated in the subventricular zone (svz) migrate to olfactory bulbs (ob). functional significance of this continuous neurogenesis is not clear. we injected opossums (monodelphis domestica) for seven consecutive days with a 5ht(1a) agonist (8-oh-dpat or buspirone) or its antagonist way100635. one hour after each of these injections bromodeoxyuridine (brdu) a marker of dividing cells was also injected. two months later, when newly generated neurons settled in the ob and ma ... | 2009 | 19593331 |
| an architectonic study of the neocortex of the short-tailed opossum (monodelphis domestica). | short-tailed opossums (monodelphis domestica) belong to the branch of marsupial mammals that diverged from eutherian mammals approximately 180 million years ago. they are small in size, lack a marsupial pouch, and may have retained more morphological characteristics of early marsupial neocortex than most other marsupials. in the present study, we used several different histochemical and immunochemical procedures to reveal the architectonic characteristics of cortical areas in short-tailed opossu ... | 2009 | 19546531 |
| developmental expression of spontaneous activity in the spinal cord of postnatal opossums, monodelphis domestica: an anatomical study. | using sulforhodamine-101 (sr101) labeling and calcium imaging on in vitro preparations, we investigated the development of spontaneous activity in the spinal enlargements of a marsupial born more immature than eutherian mammals, the opossum monodelphis domestica. following the retrograde transport of calcium green dye from the limb nerves, we observed the occurrence of spontaneous calcium waves activating the motor columns of the cervical enlargement of opossums aged from p3 to p15 (day of birth ... | 2009 | 19501058 |
| cage change intervals for opossums (monodelphis domestica) in individually ventilated cages. | the opossum monodelphis domestica is the most commonly used marsupial in biomedical research. at our institution, these opossums are housed in polycarbonate (35.6 cm × 25.4 cm × 17.8 cm) individually ventilated cages. previous studies of the cage microenvironment of rodents housed in individually ventilated cages have demonstrated that the cage-change frequency could be extended from 7 to 14 d, without detriment to the animals' wellbeing. we sought to determine whether the cage change frequency ... | 2011 | 22330710 |
| evolution of the opossum major histocompatibility complex: evidence for diverse alternative splice patterns and low polymorphism among class i genes. | the opossum major histocompatibility complex (mhc) shares a similar organization with that of non-mammals while containing a diverse set of class i genes more like that of eutherian (placental) mammals. there are 11 class i loci in the opossum mhc region, seven of which are known to be transcribed. the previously described monodelphis domestica (modo)-ua1 and modo-ug display characteristics consistent with their being classical and non-classical class i genes, respectively. here we describe the ... | 2009 | 19191910 |
| factors involved in inflammation-induced developmental white matter damage. | developmental white matter damage is a brain pathology associated with several long-term neurological disorders. an inflammatory insult has been suggested as the major instigating event. this study investigated the relative influence of inflammation, blood-brain barrier permeability and glial ontogeny in white matter damage. systemic inflammation was induced in monodelphis domestica (opossum) by serial intraperitoneal injections of lipopolysaccharide at different stages of brain development. vol ... | 2009 | 19152829 |
| behavioral and reproductive responses of female opossums to volatile and nonvolatile components of male suprasternal gland secretion. | female gray short-tailed opossums (monodelphis domestica) lack an estrous cycle and are induced into estrus by exposure to a pheromone in male scent marks. behavioral and physiological responses of females to the volatile and nonvolatile components of scent marks were examined in two experiments. young females (n=9) were tested prior to and during their first estrus for behavioral responses to scent marks, collected on a 7-ml glass vial rubbed over the suprasternal gland of a mature male. the re ... | 2008 | 18771668 |
| mechanics of generating friction during locomotion on rough and smooth arboreal trackways. | traveling on arboreal substrates is common among most small mammals living anywhere vegetation grows. because arboreal supports vary considerably in surface texture, animals must be able to adjust their locomotor biomechanics to remain stable on such supports. i examined how gray short-tailed opossums (monodelphis domestica), which are generalized marsupials living on or near the ground, adjust to travel on rough and smooth 2 cm-diameter arboreal trackways. limb contact position was determined v ... | 2009 | 19329749 |
| cellular transfer of macromolecules across the developing choroid plexus of monodelphis domestica. | choroid plexus epithelial cells secrete cerebrospinal fluid (csf) and transfer molecules from blood into csf. tight junctions between choroidal epithelial cells are functionally effective from early in development: the route of transfer is suggested to be transcellular. routes of transfer for endogenous and exogenous plasma proteins and dextrans were studied in monodelphis domestica (opossum). pups at postnatal (p) days 1-65 and young adults were injected with biotinylated dextrans (3-70 kda) an ... | 2009 | 19200232 |
| mechanics of torque generation during quadrupedal arboreal locomotion. | quadrupedal animals moving on arboreal substrates face unique challenges to maintain stability. the torque generated by the limbs around the long axis of a branch during locomotion may clarify how the animals remain stable on arboreal supports. we sought to determine what strategy gray short-tailed opossums (monodelphis domestica) use to exert torque and avoid toppling. the opossums moved across a branch trackway about half the diameter of their bodies. part of the trackway was instrumented to m ... | 2008 | 18619599 |
| thalamic nuclei in the opossum monodelphis domestica. | we investigated nuclear divisions of the thalamus in the gray short-tailed opossum (monodelphis domestica) to gain detailed information for further developmental and comparative studies. nissl and myelin staining, histochemistry for acetylcholinesterase and immunohistochemistry for calretinin and parvalbumin were performed on parallel series of sections. many features of the monodelphis opossum thalamus resemble those in didelphis and small eutherians showing no particular sensory specialization ... | 2008 | 18571895 |
| differential expression of hepatic genes involved in cholesterol homeostasis in high- and low-responding strains of laboratory opossums. | plasma very low-density lipoprotein and low-density lipoprotein (vldl+ldl) cholesterol levels of 2 partially inbred strains of opossums (monodelphis domestica) differ markedly when they are fed a high-cholesterol and low-fat (hclf) diet. high-responding opossums exhibit a dramatic increase (>10-fold) in vldl+ldl cholesterol, whereas low-responding opossums exhibit a minimal increase (<2-fold) in vldl+ldl cholesterol. the genes responsible for the accumulation of high levels of plasma vldl+ldl ch ... | 2008 | 18442639 |
| cell birth and death in the developing retina of the brazilian opossum, monodelphis domestica. | the purpose of this study was to characterize cytogenesis and apoptosis in the developing retina of the brazilian opossum, monodelphis domestica. monodelphis is a small pouchless marsupial whose young undergo a protracted period of postnatal development. moreover, the monodelphis retina represents a unique in vivo compartment for investigating cellular interactions that occur during early neural development and is an important system to study plasticity of neural stem cells following transplanta ... | 2008 | 18191114 |
| basic maintenance and breeding of the opossum monodelphis domestica. | introductionmonodelphis domestica, the gray, short-tailed, or laboratory opossum, is the most commonly used laboratory marsupial. in addition to the factors that make it a convenient laboratory animal (small size, ease of care, nonseasonal breeding), it is the first marsupial whose genome has been sequenced. monodelphis has proven useful as a model organism for studies on spinal cord regeneration, ultraviolet (uv)-induced melanoma, and genetic influences on cholesterol, as well as comparative st ... | 2008 | 21356704 |
| opossum (monodelphis domestica): a marsupial development model. | introductionmonodelphis domestica is the most commonly used laboratory marsupial. in addition to the many factors that make it a convenient laboratory animal (small size, ease of care, nonseasonal breeding), it is the first marsupial whose genome has been sequenced. in this article, we present an overview of aspects of its biology and its use as a model organism. we also discuss basic care, breeding, embryo manipulation, and modifications of common techniques for the study of the development of ... | 2008 | 21356687 |
| effect of minocycline on inflammation-induced damage to the blood-brain barrier and white matter during development. | damage to white matter in some premature infants exposed to intrauterine infections is thought to involve disruption of the blood-brain barrier. we have examined the effect of minocycline, an agent reported to reduce brain damage resulting from inflammation, on inflammation-induced disruption of the blood-brain barrier and damage to white matter. post-natal marsupial opossums (monodelphis domestica) were studied as most brain development in this species occurs after birth. single intraperitoneal ... | 2007 | 18088277 |
| meiotic sex chromosome inactivation in the marsupial monodelphis domestica. | in eutherian mammals, the x and y chromosomes undergo meiotic sex chromosome inactivation (msci) during spermatogenesis in males. however, following fertilization, both the paternally (xp) and maternally (xm) inherited x chromosomes are active in the inner cell mass of the female blastocyst, and then random inactivation of one x chromosome occurs in each cell, leading to a mosaic pattern of x-chromosome activity in adult female tissues. in contrast, marsupial females show a nonrandom pattern of ... | 2007 | 17987663 |
| marsupial uncoupling protein 1 sheds light on the evolution of mammalian nonshivering thermogenesis. | brown adipose tissue expressing uncoupling protein 1 (ucp1) is responsible for adaptive nonshivering thermogenesis giving eutherian mammals crucial advantage to survive the cold. the emergence of this thermogenic organ during mammalian evolution remained unknown as the identification of ucp1 in marsupials failed so far. here, we unequivocally identify the marsupial ucp1 ortholog in a genomic library of monodelphis domestica. in south american and australian marsupials, ucp1 is exclusively expres ... | 2008 | 17971503 |
| changes in the oviducal epithelium during the estrous cycle in the marsupial monodelphis domestica. | the monodelphis oviduct can be divided into four anatomical segments: preampulla (comprising fimbriae and infundibulum), ampulla, isthmus with crypts and uterotubal junction. ovaries are enclosed in a periovarial sac, the bursa, and in some specimens tubules of an epoophoron could be identified. in both structures non-ciliated cells develop small translucent vesicles, which accumulate in the cell apices and presumably produce fluid as often seen in the bursa and in the tubules of the epooophoron ... | 2007 | 17883438 |
| the opossum genome reveals further evidence for regulatory evolution in mammalian diversification. | the sequencing of the euchromatic genome of a marsupial, the opossum monodelphis domestica, identifies shared and unique features of marsupial and placental genomes and reveals a prominent role for the evolution of non-protein-coding elements. | 2007 | 17688679 |