Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| is salamander limb regeneration really perfect? anatomical and morphogenetic analysis of forelimb muscle regeneration in gfp-transgenic axolotls as a basis for regenerative, developmental, and evolutionary studies. | the axolotl ambystoma mexicanum is one of the most commonly used model organisms in developmental and regenerative studies because it can reconstitute what is believed to be a completely normal anatomical and functional forelimb/hindlimb after amputation. however, to date it has not been confirmed whether each regenerated forelimb muscle is really a "perfect" copy of the original muscle. this study describes the regeneration of the arm, forearm, hand, and some pectoral muscles (e.g., coracoradia ... | 2014 | 24692358 |
| precise control of mir-125b levels is required to create a regeneration-permissive environment after spinal cord injury: a cross-species comparison between salamander and rat. | most spinal cord injuries lead to permanent paralysis in mammals. by contrast, the remarkable regenerative abilities of salamanders enable full functional recovery even from complete spinal cord transections. the molecular differences underlying this evolutionary divergence between mammals and amphibians are poorly understood. we focused on upstream regulators of gene expression as primary entry points into this question. we identified a group of micrornas (mirnas) that are conserved between the ... | 2014 | 24719025 |
| new insights into vertebrate skin regeneration. | regeneration biology has experienced a renaissance as clinicians, scientists, and engineers have combined forces to drive the field of regenerative medicine. studies investigating the mechanisms that regulate wound healing in adult mammals have led to a good understanding of the stereotypical processes that lead to scarring. despite comparative studies of fetal wound healing in which no scar is produced, the fact remains that insights from this work have failed to produce therapies that can rege ... | 2014 | 24725426 |
| highly efficient targeted mutagenesis in axolotl using cas9 rna-guided nuclease. | among tetrapods, only urodele salamanders, such as the axolotl ambystoma mexicanum, can completely regenerate limbs as adults. the mystery of why salamanders, but not other animals, possess this ability has for generations captivated scientists seeking to induce this phenomenon in other vertebrates. although many recent advances in molecular biology have allowed limb regeneration and tissue repair in the axolotl to be investigated in increasing detail, the molecular toolkit for the study of this ... | 2014 | 24764077 |
| evolving possibilities: post-embryonic axial elongation in salamanders with biphasic (eurcyea cirrigera, e. longicauda, e. quadridigitata) and paedomorphic life cycles (eurycea nana and ambystoma mexicanum). submitted acta zoologica. | typically the number of vertebrae an organism will have post-embryonically is determined during embryogenesis via the development of paired somites. our research investigates the phenomenon of post-embryonic vertebral addition in salamander tails. we describe body and tail growth, and patterns of postsacral vertebral addition and elongation in context with caudal morphology for four plethodontids (eurycea), and one ambystomatid. eurycea nana and a. mexicanum have paedomorphic life cycles; e. cir ... | 2012 | 24790225 |
| mapping hematopoiesis in a fully regenerative vertebrate: the axolotl. | hematopoietic stem cell (hsc)-derived cells are involved in wound healing responses throughout the body. unfortunately for mammals, wound repair typically results in scarring and nonfunctional reparation. among vertebrates, none display such an extensive ability for adult regeneration as urodele amphibians, including 1 of the more popular models: the axolotl. however, a lack of knowledge of axolotl hematopoiesis hinders the use of this animal for the study of hematopoietic cells in scar-free wou ... | 2014 | 24802774 |
| preparation of primary myogenic precursor cell/myoblast cultures from basal vertebrate lineages. | due to the inherent difficulty and time involved with studying the myogenic program in vivo, primary culture systems derived from the resident adult stem cells of skeletal muscle, the myogenic precursor cells (mpcs), have proven indispensible to our understanding of mammalian skeletal muscle development and growth. particularly among the basal taxa of vertebrata, however, data are limited describing the molecular mechanisms controlling the self-renewal, proliferation, and differentiation of mpcs ... | 2014 | 24835774 |
| stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos. | a common feature of development in most vertebrate models is the early segregation of the germ line from the soma. for example, in xenopus and zebrafish embryos primordial germ cells (pgcs) are specified by germ plasm that is inherited from the egg; in mice, blimp1 expression in the epiblast mediates the commitment of cells to the germ line. how these disparate mechanisms of pgc specification evolved is unknown. here, in order to identify the ancestral mechanism of pgc specification in vertebrat ... | 2014 | 24917499 |
| notochord-derived hedgehog is essential for tail regeneration in xenopus tadpole. | appendage regeneration in amphibians is regulated by the combinatorial actions of signaling molecules. the requirement of molecules secreted from specific tissues is reflected by the observation that the whole process of regeneration can be inhibited if a certain tissue is removed from the amputated stump. interestingly, urodeles and anurans show different tissue dependencies during tail regeneration. the spinal cord is essential for tail regeneration in urodele but not in anuran larva, whereas ... | 2014 | 24941877 |
| expression of sarcomeric tropomyosin in striated muscles in axolotl treated with shz-1, a small cardiogenic molecule. | we evaluated the effect of shz-1, a cardiogenic molecule, on the expression of various tropomyosin (tm) isoforms in the mexican axolotl (ambystoma mexicanum) hearts. qrt-pcr data show a ~1.5-fold increase in cardiac transcripts of the nkx2.5 gene, which plays a crucial role in cardiogenesis in vertebrates. shz-1 augments the expression of transcripts of the total sarcomeric tpm1 (both tpm1α & tpm1κ) and sarcomeric tpm4α. in order to understand the mechanism by which shz-1 augments the expression ... | 2015 | 24958154 |
| proteomic analysis of fibroblastema formation in regenerating hind limbs of xenopus laevis froglets and comparison to axolotl. | to gain insight into what differences might restrict the capacity for limb regeneration in xenopus froglets, we used high performance liquid chromatography (hplc)/double mass spectrometry to characterize protein expression during fibroblastema formation in the amputated froglet hindlimb, and compared the results to those obtained previously for blastema formation in the axolotl limb. | 2014 | 25063185 |
| axolotls with an under- or oversupply of neural crest can regulate the sizes of their dorsal root ganglia to normal levels. | how animals adjust the size of their organs is a fundamental, enduring question in biology. here we manipulate the amount of neural crest (nc) precursors for the dorsal root ganglia (drg) in axolotl. we produce embryos with an under- or over-supply of pre-migratory nc in order to find out if drg can regulate their sizes during development. axolotl embryos are perfectly suitable for this research. firstly, they are optimal for microsurgical manipulations and tissue repair. secondly, they possess, ... | 2014 | 25111151 |
| translational control of tropomyosin expression in vertebrate hearts. | the tropomyosin (tm) gene family produces a set of related tm proteins with important functions in striated and smooth muscle, and nonmuscle cells. in vertebrate striated muscle, the thin filament consists largely of actin, tm, the troponin (tn) complex (tn-i, tn-c and tn-t), and tropomodulin (tmod) and is responsible for mediating ca(2+) control of muscle contraction and relaxation. there are four known genes (designated as tpm1, tpm2, tpm3, and tpm4) for tm in vertebrates. the four tm genes ge ... | 2014 | 25125172 |
| hematopoietic ontogeny in the axolotl. | 2014 | 25147373 | |
| comparative and phylogenetic perspectives of the cleavage process in tailed amphibians. | the order caudata includes about 660 species and displays a variety of important developmental traits such as cleavage pattern and egg size. however, the cleavage process of tailed amphibians has never been analyzed within a phylogenetic framework. we use published data on the embryos of 36 species concerning the character of the third cleavage furrow (latitudinal, longitudinal or variable) and the magnitude of synchronous cleavage period (up to 3-4 synchronous cell divisions in the animal hemis ... | 2015 | 25180466 |
| crispr-mediated genomic deletion of sox2 in the axolotl shows a requirement in spinal cord neural stem cell amplification during tail regeneration. | the salamander is the only tetrapod that functionally regenerates all cell types of the limb and spinal cord (sc) and thus represents an important regeneration model, but the lack of gene-knockout technology has limited molecular analysis. we compared transcriptional activator-like effector nucleases (talens) and clustered regularly interspaced short palindromic repeats (crisprs) in the knockout of three loci in the axolotl and find that crisprs show highly penetrant knockout with less toxic eff ... | 2014 | 25241743 |
| co-operative bmp- and fgf-signaling inputs convert skin wound healing to limb formation in urodele amphibians. | urodele amphibians have remarkable organ regeneration capability, and their limb regeneration capability has been investigated as a representative phenomenon. in the early 19th century, nerves were reported to be an essential tissue for the successful induction of limb regeneration. nerve substances that function in the induction of limb regeneration responses have long been sought. a new experimental system called the accessory limb model (alm) has been established to identify the nerve factors ... | 2014 | 25286122 |
| successful nucleofection of rat adipose-derived stroma cells with ambystoma mexicanum epidermal lipoxygenase (ambloxe). | adipose-derived stroma cells (ascs) are attractive cells for cell-based gene therapy but are generally difficult to transfect. nucleofection has proven to be an efficient method for transfection of primary cells. therefore, we used this technique to transfect ascs with a vector encoding for ambystoma mexicanum epidermal lipoxygenase (ambloxe) which is a promising bioactive enzyme in regenerative processes. thereby, we thought to even further increase the large regenerative potential of the ascs. | 2014 | 25300230 |
| dynamic evolution of the gnrh receptor gene family in vertebrates. | elucidating the mechanisms underlying coevolution of ligands and receptors is an important challenge in molecular evolutionary biology. peptide hormones and their receptors are excellent models for such efforts, given the relative ease of examining evolutionary changes in genes encoding for both molecules. most vertebrates possess multiple genes for both the decapeptide gonadotropin releasing hormone (gnrh) and for the gnrh receptor. the evolutionary history of the receptor family, including anc ... | 2014 | 25344287 |
| identification of a human mitochondrial rna that promotes tropomyosin synthesis and myocardial differentiation. | heart disease is the number one killer in the usa, making cardiogenesis and its related pathways a relevant area of study for improving health and life expectancy. the mexican salamander (axolotl), ambystoma mexicanum, provides an excellent vertebrate animal model for studying myofibrillogenesis due to its naturally occurring cardiac nonfunction mutation. homozygous recessive embryos do not develop normal hearts due to a lack of myofibril formation. in previous studies, myofibril-inducing ribonu ... | 2015 | 25408381 |
| immunocytochemical characterisation of ensheathing glia in the olfactory and vomeronasal systems of ambystoma mexicanum (caudata: ambystomatidae). | the olfactory and vomeronasal systems of vertebrates are characterised by neurogenesis occurring throughout life. the regenerative ability of olfactory receptor neurons relies on specific glial cells, the olfactory and vomeronasal axon-surrounding cells. numerous studies have examined mammalian olfactory ensheathing cells which are considered potential candidates for spinal cord injury repair using cell-based therapy. with regard to non-mammalian vertebrates, limited information is available on ... | 2016 | 25433448 |
| evolutionary innovation and conservation in the embryonic derivation of the vertebrate skull. | development of the vertebrate skull has been studied intensively for more than 150 years, yet many essential features remain unresolved. one such feature is the extent to which embryonic derivation of individual bones is evolutionarily conserved or labile. we perform long-term fate mapping using gfp-transgenic axolotl and xenopus laevis to document the contribution of individual cranial neural crest streams to the osteocranium in these amphibians. here we show that the axolotl pattern is strikin ... | 2014 | 25434971 |
| homodimeric anoctamin-1, but not homodimeric anoctamin-6, is activated by calcium increases mediated by the p2y1 and p2x7 receptors. | the p2x7 receptor (p2x7r) is a ligand-gated ion channel that conducts na(+), k(+), and ca(2+) when activated by extracellular atp. in various cell types, such as secretory epithelia, the p2x7r is co-expressed with ca(2+)-dependent cl(-) channels of the tmem16/anoctamin family. here, we studied whether the p2x7r and tmem16a/anoctamin-1 (ano1) or tmem16f/anoctamin-6 (ano6) interact functionally and physically, using oocytes of xenopus laevis and ambystoma mexicanum (axolotl) for heterologous expre ... | 2015 | 25592660 |
| evaluation of de novo transcriptome assemblies from rna-seq data. | de novo rna-seq assembly facilitates the study of transcriptomes for species without sequenced genomes, but it is challenging to select the most accurate assembly in this context. to address this challenge, we developed a model-based score, rsem-eval, for evaluating assemblies when the ground truth is unknown. we show that rsem-eval correctly reflects assembly accuracy, as measured by ref-eval, a refined set of ground-truth-based scores that we also developed. guided by rsem-eval, we assembled t ... | 2014 | 25608678 |
| presence and prevalence of batrachochytrium dendrobatidis in commercial amphibians in mexico city. | in mexico city, native and exotic amphibians are commonly sold through the pet trade. this study investigates the presence of batrachochytrium dendrobatidis (bd) in native amphibians being sold at two commercial markets and at a herpetarium in mexico city. a total of 238 individuals (6 genera and 12 species) were tested for bd using real-time polymerase chain reaction (pcr) analysis. there were 197 bd-positive individuals (prevalence 82%) from five species of amphibians. hyla eximia from the mar ... | 2014 | 25632670 |
| identification of reference genes and validation for gene expression studies in diverse axolotl (ambystoma mexicanum) tissues. | for the precise quantitative rt-pcr normalization a set of valid reference genes is obligatory. moreover have to be taken into concern the experimental conditions as they bias the regulation of reference genes. up till now, no reference targets have been described for the axolotl (ambystoma mexicanum). in a search in the public database salsite for genetic information of the axolotl we identified fourteen presumptive reference genes, eleven of which were further tested for their gene expression ... | 2015 | 25637570 |
| long-duration muscle dedifferentiation during limb regeneration in axolotls. | although still debated, limb regeneration in salamanders is thought to depend on the dedifferentiation of remnant tissue occurring early after amputation and generating the progenitor cells that initiate regeneration. this dedifferentiation has been demonstrated previously by showing the fragmentation of muscle fibers into mononucleated cells and by revealing the contribution of mature muscle fibers to the regenerates by using lineage-tracing studies. here, we provide additional evidence of dedi ... | 2015 | 25671422 |
| vesicular stomatitis virus enables gene transfer and transsynaptic tracing in a wide range of organisms. | current limitations in technology have prevented an extensive analysis of the connections among neurons, particularly within nonmammalian organisms. we developed a transsynaptic viral tracer originally for use in mice, and then tested its utility in a broader range of organisms. by engineering the vesicular stomatitis virus (vsv) to encode a fluorophore and either the rabies virus glycoprotein (rabv-g) or its own glycoprotein (vsv-g), we created viruses that can transsynaptically label neuronal ... | 2015 | 25688551 |
| [on the classification of the cleavage patterns in amphibian embryos]. | this paper presents a brief survey and preliminary classification of embryonic cleavage patterns in the class amphibia. we use published data on 41 anuran and 22 urodele species concerning the character of the third cleavage furrow (latitudinal or longitudinal) and the stage of transition from synchronous to asynchronous blastomere divisions in the animal hemisphere (4-8-celled stage, 8-16-celled stage or later). based on this, four patterns of amphibian embryonic cleavage are recognized, and an ... | 2015 | 25720261 |
| housing and maintenance of ambystoma mexicanum, the mexican axolotl. | the aim of this paper is to assemble a significant amount of information on ambystoma mexicanum, the axolotl salamander, to assist in the basic knowledge needed to raise, breed, and study most aspects of axolotl biology. it is important to understand the basic biology of the axolotl in order to make informed decisions on their proper care and use in experiments. therefore, we will provide necessary information to the non-herpetologist that will assist in their study of this unique and fascinatin ... | 2015 | 25740475 |
| studying newt brain regeneration following subtype specific neuronal ablation. | the realization that neuronal injury does not result in permanent functional or cellular loss in all vertebrates has fascinated regenerative biologists. neuronal regeneration occurs in a subset of species, including lizards, teleost fish, axolotls, and newts. one tool for studying neuronal regeneration in the adult brain is intraventricular injection of selective neuronal toxins, which leads to loss of subpopulations of neurons. to trace cells involved in the regeneration process, plasmids encod ... | 2015 | 25740479 |
| high-efficiency electroporation of the spinal cord in larval axolotl. | axolotls are well known for their remarkable ability to regenerate complex body parts and structures throughout life, including the entire limb and tail. particularly fascinating is their ability to regenerate a fully functional spinal cord after losing the tail. electroporation of dna plasmids or morpholinos is a valuable tool to gain mechanistic insight into the cellular and molecular basis of regeneration. it provides among other advantages a simple and fast method to test gene function in a ... | 2015 | 25740481 |
| pseudotyped retroviruses for infecting axolotl. | the ability to introduce dna elements into host cells and analyze the effects has revolutionized modern biology. here we describe a protocol to generate moloney murine leukemia virus (mmlv)-based, replication-incompetent pseudotyped retrovirus capable of infecting axolotls and incorporating genetic information into their genome. when pseudotyped with vesicular stomatitis virus (vsv)-g glycoprotein, the retroviruses can infect a broad range of proliferative axolotl cell types. however, if the ret ... | 2015 | 25740482 |
| thyroxine-induced metamorphosis in the axolotl (ambystoma mexicanum). | the axolotl (ambystoma mexicanum) has remained an important model for regeneration and developmental biology for over a century. although axolotls in captive-bred colonies usually exist in an aquatic form, they retain the ability to undergo metamorphosis following exposure to thyroid hormone. here we present a robust method for inducing metamorphosis in adult axolotls that results in high survivability and produces terrestrial animals that can be maintained in long-term captivity. | 2015 | 25740483 |
| in vivo modulation and quantification of micrornas during axolotl tail regeneration. | the ability to regenerate diseased, injured, or missing complex tissue is widespread throughout lower vertebrates and invertebrates; however, our knowledge of the molecular mechanisms that regulate this amazing ability is still in its infancy. many recent papers have shown important roles for micrornas in regulating regeneration in a number of species. the ability to detect and quantify mirna expression fluctuations at a single cell level in vivo in different cell types during processes like reg ... | 2015 | 25740485 |
| culture and transfection of axolotl cells. | the use of cells grown in vitro has been instrumental for multiple aspects of biomedical research and especially molecular and cellular biology. the ability to grow cells from multicellular organisms like humans, squids, or salamanders is important to simplify the analyses and experimental designs to help understand the biology of these organisms. the advent of the first cell culture has allowed scientists to tease apart the cellular functions, and in many situations these experiments help under ... | 2015 | 25740487 |
| methods for axolotl blood collection, intravenous injection, and efficient leukocyte isolation from peripheral blood and the regenerating limb. | the vertebrate immune system comprises both adaptive and innate immune cells with distinct functions during the resolution of inflammation and wound healing after tissue injury. recent evidence implicates a requirement for innate immune cells from the myeloid lineage during the early stages of limb regeneration in the mexican axolotl. understanding the functions of innate and adaptive immune cells in the axolotl has been hampered by a lack of approaches to isolate and analyze these cells. here w ... | 2015 | 25740489 |
| transgenesis in axolotl (ambystoma mexicanum). | transgenic animals have been indispensable in elucidating and deciphering mechanisms underlying various biological phenomena. in regeneration, transgenic animals expressing fluorescent protein genes have been crucial for identifying the source cells for regeneration and the mechanism of blastema formation. animals are usually generated by manipulating their genome using various techniques at/in one cell embryo/fertilized egg stage. here, we describe the generation of germline transgenic axolotls ... | 2015 | 25740493 |
| generating and identifying axolotls with targeted mutations using cas9 rna-guided nuclease. | the crispr/cas9 rna-guided nuclease now enables a reverse genetics approach to investigate the function of genes of interest during regeneration in the axolotl. the process of generating the constructs necessary for targeting a gene of interest is considerably less labor intensive than for other methods of targeted mutagenesis such as zinc finger nucleases or transcription activator-like effector nucleases. here, we describe the identification of targetable sequences in the gene of interest, the ... | 2015 | 25740494 |
| transcriptomics using axolotls. | microarray and rna-sequencing technology now exists for the characterization of the ambystoma mexicanum transcriptome. with sufficient replication, these tools give the opportunity to truly investigate gene expression in a variety of experimental paradigms. analysis of data from the amby002 array and rna-sequencing technology can identify genes that change expression levels in concert with each other, which in turn may reveal mechanisms associated with biological processes and molecular function ... | 2015 | 25740496 |
| sal-site: research resources for the mexican axolotl. | sal-site serves axolotl research efforts by providing web access to genomic data and information, and living stocks that are reared and made available by the ambystoma genetic stock center (agsc). in this chapter, we detail how investigators can search for genes of interest among sal-site resources to identify orthologous nucleotide and protein-coding sequences, determine genome positions within the ambystoma meiotic map, and obtain estimates of gene expression. in the near future, additional ge ... | 2015 | 25740497 |
| probability of regenerating a normal limb after bite injury in the mexican axolotl (ambystoma mexicanum). | multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. we examined adult and juvenile axolotls (ambystoma mexicanum) in the ambystoma genetic stock center (agsc) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. we observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. among 7 ... | 2014 | 25745564 |
| characterization of in vitro transcriptional responses of dorsal root ganglia cultured in the presence and absence of blastema cells from regenerating salamander limbs. | during salamander limb regeneration, nerves provide signals that induce the formation of a mass of proliferative cells called the blastema. to better understand these signals, we developed a blastema-dorsal root ganglia (drg) co-culture model system to test the hypothesis that nerves differentially express genes in response to cues provided by the blastema. drg with proximal and distal nerve trunks were isolated from axolotls (ambystoma mexicanum), cultured for five days, and subjected to microa ... | 2014 | 25750744 |
| cooperative regulation of substrate stiffness and extracellular matrix proteins in skin wound healing of axolotls. | urodele amphibians (ambystoma mexicanum), unique among vertebrates, can regenerate appendages and other body parts entirely and functionally through a scar-free healing process. the wound epithelium covering the amputated or damaged site forms early and is essential for initiating the subsequent regenerative steps. however, the molecular mechanism through which the wound reepithelializes during regeneration remains unclear. in this study, we developed an in vitro culture system that mimics an in ... | 2015 | 25839038 |
| analysis of signal processing in vestibular circuits with a novel light-emitting diodes-based fluorescence microscope. | optical visualization of neural network activity is limited by imaging system-dependent technical tradeoffs. to overcome these constraints, we have developed a powerful low-cost and flexible imaging system with high spectral variability and unique spatio-temporal precision for simultaneous optical recording and manipulation of neural activity of large cell groups. the system comprises eight high-power light-emitting diodes, a camera with a large metal-oxide-semiconductor sensor and a high numeri ... | 2015 | 25847143 |
| the history of the oldest self-sustaining laboratory animal: 150 years of axolotl research. | today the mexican axolotl is critically endangered in its natural habitat in lakes around mexico city, but thrives in research laboratories around the world, where it is used for research on development, regeneration, and evolution. here, we concentrate on the early history of the axolotl as a laboratory animal to celebrate that the first living axolotls arrived in paris in 1864, 150 years ago. maybe surprisingly, at first the axolotl was distributed across europe without being tied to specific ... | 2015 | 25920413 |
| regulation of axolotl (ambystoma mexicanum) limb blastema cell proliferation by nerves and bmp2 in organotypic slice culture. | we have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possi ... | 2015 | 25923915 |
| an aryl hydrocarbon receptor from the salamander ambystoma mexicanum exhibits low sensitivity to 2,3,7,8-tetrachlorodibenzo-p-dioxin. | structural features of the aryl hydrocarbon receptor (ahr) can underlie species- and population-specific differences in its affinity for 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd). these differences often explain variations in tcdd toxicity. frogs are relatively insensitive to dioxin, and xenopus ahrs bind tcdd with low affinity. weak tcdd binding results from the combination of three residues in the ligand-binding domain: a354 and a370, and n325. here we sought to determine whether this mechani ... | 2015 | 25941739 |
| recurrent turnover of senescent cells during regeneration of a complex structure. | cellular senescence has been recently linked to the promotion of age-related pathologies, including a decline in regenerative capacity. while such capacity deteriorates with age in mammals, it remains intact in species such as salamanders, which have an extensive repertoire of regeneration and can undergo multiple episodes through their lifespan. here we show that, surprisingly, there is a significant induction of cellular senescence during salamander limb regeneration, but that rapid and effect ... | 2015 | 25942455 |
| dual embryonic origin and patterning of the pharyngeal skeleton in the axolotl (ambystoma mexicanum). | the impressive morphological diversification of vertebrates was achieved in part by innovation and modification of the pharyngeal skeleton. extensive fate mapping in amniote models has revealed a primarily cranial neural crest derivation of the pharyngeal skeleton. although comparable fate maps of amphibians produced over several decades have failed to document a neural crest derivation of ventromedial elements in these vertebrates, a recent report provides evidence of a mesodermal origin of one ... | 2015 | 25963195 |
| expression of tropomyosin in relation to myofibrillogenesis in axolotl hearts. | the anatomy, function and embryonic development of the heart have been of interest to clinicians and researchers alike for centuries. a beating heart is one of the key criteria in defining life or death in humans. an understanding of the multitude of genetic and functional elements that interplay to form such a complex organ is slowly evolving with new genetic, molecular and experimental techniques. despite the need for ever more complex molecular techniques some of our biggest leaps in knowledg ... | 2013 | 25984327 |
| mesodermal origin of median fin mesenchyme and tail muscle in amphibian larvae. | mesenchyme is an embryonic precursor tissue that generates a range of structures in vertebrates including cartilage, bone, muscle, kidney, and the erythropoietic system. mesenchyme originates from both mesoderm and the neural crest, an ectodermal cell population, via an epithelial to mesenchymal transition (emt). because ectodermal and mesodermal mesenchyme can form in close proximity and give rise to similar derivatives, the embryonic origin of many mesenchyme-derived tissues is still unclear. ... | 2015 | 26086331 |
| using ambystoma mexicanum (mexican axolotl) embryos, chemical genetics, and microarray analysis to identify signaling pathways associated with tissue regeneration. | amphibian vertebrates are important models in regenerative biology because they present exceptional regenerative capabilities throughout life. however, it takes considerable effort to rear amphibians to juvenile and adult stages for regeneration studies, and the relatively large sizes that frogs and salamanders achieve during development make them difficult to use in chemical screens. here, we introduce a new tail regeneration model using late stage mexican axolotl embryos. we show that axolotl ... | 2015 | 26092703 |
| the axolotl fibula as a model for the induction of regeneration across large segment defects in long bones of the extremities. | we tested the ability of the axolotl (ambystoma mexicanum) fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (sis) scaffold, with or without incorporated growth factor combinations or tissue protein extract. fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of b ... | 2015 | 26098852 |
| regeneration inducers in limb regeneration. | limb regeneration ability, which can be observed in amphibians, has been investigated as a representative phenomenon of organ regeneration. recently, an alternative experimental system called the accessory limb model was developed to investigate early regulation of amphibian limb regeneration. the accessory limb model contributed to identification of limb regeneration inducers in urodele amphibians. furthermore, the accessory limb model may be applied to other species to explore universality of ... | 2015 | 26100345 |
| comparative analysis of cartilage marker gene expression patterns during axolotl and xenopus limb regeneration. | axolotls (ambystoma mexicanum) can completely regenerate lost limbs, whereas xenopus laevis frogs cannot. during limb regeneration, a blastema is first formed at the amputation plane. it is thought that this regeneration blastema forms a limb by mechanisms similar to those of a developing embryonic limb bud. furthermore, xenopus laevis frogs can form a blastema after amputation; however, the blastema results in a terminal cone-shaped cartilaginous structure called a "spike." the causes of this p ... | 2015 | 26186213 |
| primordial germ cells: the first cell lineage or the last cells standing? | embryos of many animal models express germ line determinants that suppress transcription and mediate early germ line commitment, which occurs before the somatic cell lineages are established. however, not all animals segregate their germ line in this manner. the 'last cell standing' model describes primordial germ cell (pgc) development in axolotls, in which pgcs are maintained by an extracellular signalling niche, and germ line commitment occurs after gastrulation. here, we propose that this 's ... | 2015 | 26286941 |
| dna methylation dynamics regulate the formation of a regenerative wound epithelium during axolotl limb regeneration. | the formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. one of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. we have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression pattern ... | 2015 | 26308461 |
| immunodetection of telomerase-like immunoreactivity in normal and regenerating tail of amphibians suggests it is related to their regenerative capacity. | the high regenerative power of amphibians suggests that numerous signaling pathways remain active in larvae and adult tissues, including those stimulated by telomerases. the protein component of telomerase (tert) shows high amino acid homology in numerous vertebrates and we have utilized an antibody made for a lizard telomerase to detect a putative telomerase in amphibians tissues based on 60-75% epitope identity. western blotting studies indicate that telomerase is constitutionally present in n ... | 2015 | 26351773 |
| generation of axolotl hematopoietic chimeras. | wound repair is an extremely complex process that requires precise coordination between various cell types including immune cells. unfortunately, in mammals this usually results in scar formation instead of restoration of the original fully functional tissue, otherwise known as regeneration. various animal models like frogs and salamanders are currently being studied to determine the intracellular and intercellular pathways, controlled by gene expression, that elicit cell proliferation, differen ... | 2015 | 26366424 |
| identification of conserved and novel micrornas during tail regeneration in the mexican axolotl. | the mexican axolotl salamander (ambystoma mexicanum) is one member of a select group of vertebrate animals that have retained the amazing ability to regenerate multiple body parts. in addition to being an important model system for regeneration, the axolotl has also contributed extensively to studies of basic development. while many genes known to play key roles during development have now been implicated in various forms of regeneration, much of the regulatory apparatus controlling the underlyi ... | 2015 | 26378530 |
| hyperbaric oxygen promotes proximal bone regeneration and organized collagen composition during digit regeneration. | oxygen is critical for optimal bone regeneration. while axolotls and salamanders have retained the ability to regenerate whole limbs, mammalian regeneration is restricted to the distal tip of the digit (p3) in mice, primates, and humans. our previous study revealed the oxygen microenvironment during regeneration is dynamic and temporally influential in building and degrading bone. given that regeneration is dependent on a dynamic and changing oxygen environment, a better understanding of the eff ... | 2015 | 26452224 |
| dynamic membrane depolarization is an early regulator of ependymoglial cell response to spinal cord injury in axolotl. | salamanders, such as the mexican axolotl, are some of the few vertebrates fortunate in their ability to regenerate diverse structures after injury. unlike mammals they are able to regenerate a fully functional spinal cord after injury. however, the molecular circuitry required to initiate a pro-regenerative response after spinal cord injury is not well understood. to address this question we developed a spinal cord injury model in axolotls and used in vivo imaging of labeled ependymoglial cells ... | 2015 | 26477559 |
| linking vertebral number to performance of aquatic escape responses in the axolotl (ambystoma mexicanum). | environmental conditions during early development in ectothermic vertebrates can lead to variation in vertebral number among individuals of the same species. it is often seen that individuals of a species raised at cooler temperatures have more vertebrae than individuals raised at warmer temperatures, although the functional consequences of this variation in vertebral number on swimming performance are relatively unclear. to investigate this relationship, we tested how vertebral number in axolot ... | 2015 | 26489369 |
| changes in regenerative capacity through lifespan. | most organisms experience changes in regenerative abilities through their lifespan. during aging, numerous tissues exhibit a progressive decline in homeostasis and regeneration that results in tissue degeneration, malfunction and pathology. the mechanisms responsible for this decay are both cell intrinsic, such as cellular senescence, as well as cell-extrinsic, such as changes in the regenerative environment. understanding how these mechanisms impact on regenerative processes is essential to dev ... | 2015 | 26512653 |
| initial characterization of the large genome of the salamander ambystoma mexicanum using shotgun and laser capture chromosome sequencing. | vertebrates exhibit substantial diversity in genome size, and some of the largest genomes exist in species that uniquely inform diverse areas of basic and biomedical research. for example, the salamander ambystoma mexicanum (the mexican axolotl) is a model organism for studies of regeneration, development and genome evolution, yet its genome is ~10× larger than the human genome. as part of a hierarchical approach toward improving genome resources for the species, we generated 600 gb of shotgun s ... | 2015 | 26553646 |
| planar cell polarity-mediated induction of neural stem cell expansion during axolotl spinal cord regeneration. | axolotls are uniquely able to mobilize neural stem cells to regenerate all missing regions of the spinal cord. how a neural stem cell under homeostasis converts after injury to a highly regenerative cell remains unknown. here, we show that during regeneration, axolotl neural stem cells repress neurogenic genes and reactivate a transcriptional program similar to embryonic neuroepithelial cells. this dedifferentiation includes the acquisition of rapid cell cycles, the switch from neurogenic to pro ... | 2015 | 26568310 |
| positional plasticity in regenerating amybstoma mexicanum limbs is associated with cell proliferation and pathways of cellular differentiation. | the endogenous ability to dedifferentiate, re-pattern, and re-differentiate adult cells to repair or replace damaged or missing structures is exclusive to only a few tetrapod species. the mexican axolotl is one example of these species, having the capacity to regenerate multiple adult structures including their limbs by generating a group of progenitor cells, known as the blastema, which acquire pattern and differentiate into the missing tissues. the formation of a limb regenerate is dependent o ... | 2015 | 26597593 |
| cellular dynamics underlying regeneration of appropriate segment number during axolotl tail regeneration. | salamanders regenerate their tails after amputation anywhere along their length. how the system faithfully reconstitutes the original number of segments and length is not yet known. | 2015 | 26647066 |
| cooperative inputs of bmp and fgf signaling induce tail regeneration in urodele amphibians. | urodele amphibians have remarkable organ regeneration ability. they can regenerate not only limbs but also a tail throughout their life. it has been demonstrated that the regeneration of some organs are governed by the presence of neural tissues. for instance, limb regeneration cannot be induced without nerves. thus, identifying the nerve factors has been the primary focus in amphibian organ regeneration research. recently, substitute molecules for nerves in limb regeneration, bmp and fgfs, were ... | 2016 | 26703427 |
| the evolution of basal progenitors in the developing non-mammalian brain. | the amplification of distinct neural stem/progenitor cell subtypes during embryogenesis is essential for the intricate brain structures present in various vertebrate species. for example, in both mammals and birds, proliferative neuronal progenitors transiently appear on the basal side of the ventricular zone of the telencephalon (basal progenitors), where they contribute to the enlargement of the neocortex and its homologous structures. in placental mammals, this proliferative cell population c ... | 2016 | 26732839 |
| tissue specific reactions to positional discontinuities in the regenerating axolotl limb. | we investigated cellular contributions to intercalary regenerates and 180° supernumerary limbs during axolotl limb regeneration using the cell autonomous gfp marker and exchanged blastemas between white and gfp animals. after distal blastemas were grafted to proximal levels tissues of the intercalary regenerate behaved independently with regard to the law of distal transformation; graft epidermis was replaced by stump epidermis, muscle-derived cells, blood vessels and schwann cells of the distal ... | 2015 | 26755943 |
| localization of amylin-like immunoreactivity in melanocyte-stimulating hormone-containing cells of the pars intermedia but not those of the pars distalis in the axolotl (ambystoma mexicanum) pituitary. | immunohistochemical techniques were employed to investigate the distribution of amylin-like immunoreactivity in the axolotl (ambystoma mexicanum) pituitary. amylin-immunoreactive cells were observed in the pars intermedia, and these cells were found to be immunoreactive for α-melanocyte-stimulating hormone (αmsh) as well. in contrast, αmsh-immunoreactive cells in the pars distalis were immuno-negaitive for amylin. these light microscopic findings were confirmed by immunoelectron microscopy. amyl ... | 2016 | 26797189 |
| courtship pheromone use in a model urodele, the mexican axolotl (ambystoma mexicanum). | sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. until now, courtship pheromones of salamandridae and plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. the axolotl (ambystoma mexicanum, ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characteriz ... | 2016 | 26842386 |
| proteinaceous pheromone homologs identified from the cloacal gland transcriptome of a male axolotl, ambystoma mexicanum. | pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. the first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male cynops pyrrhogaster. other proteinaceous pheromones in salamanders have been shown to elicit resp ... | 2016 | 26885665 |
| marcks-like protein is an initiating molecule in axolotl appendage regeneration. | identifying key molecules that launch regeneration has been a long-sought goal. multiple regenerative animals show an initial wound-associated proliferative response that transits into sustained proliferation if a considerable portion of the body part has been removed. in the axolotl, appendage amputation initiates a round of wound-associated cell cycle induction followed by continued proliferation that is dependent on nerve-derived signals. a wound-associated molecule that triggers the initial ... | 2016 | 26934225 |
| multicellular mathematical modelling of mesendoderm formation in amphibians. | the earliest cell fate decisions in a developing embryo are those associated with establishing the germ layers. the specification of the mesoderm and endoderm is of particular interest as the mesoderm is induced from the endoderm, potentially from an underlying bipotential group of cells, the mesendoderm. mesendoderm formation has been well studied in an amphibian model frog, xenopus laevis, and its formation is driven by a gene regulatory network (grn) induced by maternal factors deposited in t ... | 2016 | 26934886 |
| the role of stem cells in limb regeneration. | limb regeneration is a complex yet fascinating process observed to some extent in many animal species, though seen in its entirety in urodele amphibians. accomplished by formation of a morphologically uniform intermediate, the blastema, scientists have long attempted to define the cellular constituents that enable regrowth of a functional appendage. today, we know that the blastema consists of a variety of multipotent progenitor cells originating from a variety of tissues, and which contribute t ... | 2016 | 27008101 |
| evolution of the head-trunk interface in tetrapod vertebrates. | vertebrate neck musculature spans the transition zone between head and trunk. the extent to which the cucullaris muscle is a cranial muscle allied with the gill levators of anamniotes or is instead a trunk muscle is an ongoing debate. novel computed tomography datasets reveal broad conservation of the cucullaris in gnathostomes, including coelacanth and caecilian, two sarcopterygians previously thought to lack it. in chicken, lateral plate mesoderm (lpm) adjacent to occipital somites is a recent ... | 2016 | 27090084 |
| fgf8 and shh substitute for anterior-posterior tissue interactions to induce limb regeneration. | in salamanders, grafting of a left limb blastema onto a right limb stump yields regeneration of three limbs, the normal limb and two 'supernumerary' limbs. this experiment and other research have shown that the juxtaposition of anterior and posterior limb tissue plus innervation are necessary and sufficient to induce complete limb regeneration in salamanders. however, the cellular and molecular basis of the requirement for anterior-posterior tissue interactions were unknown. here we have clarifi ... | 2016 | 27120163 |
| expression analysis of baf60c during heart regeneration in axolotls and neonatal mice. | some organisms, such as zebrafish, urodele amphibians, and newborn mice, have a capacity for heart regeneration following injury. however, adult mammals fail to regenerate their hearts. to know why newborn mice can regenerate their hearts, we focused on epigenetic factors, which are involved in cell differentiation in many tissues. baf60c (brg1/brm-associated factor 60c), a component of atp-dependent chromatin-remodeling complexes, has an essential role for cardiomyocyte differentiation at the e ... | 2016 | 27125315 |
| adult axolotls can regenerate original neuronal diversity in response to brain injury. | the axolotl can regenerate multiple organs, including the brain. it remains, however, unclear whether neuronal diversity, intricate tissue architecture, and axonal connectivity can be regenerated; yet, this is critical for recovery of function and a central aim of cell replacement strategies in the mammalian central nervous system. here, we demonstrate that, upon mechanical injury to the adult pallium, axolotls can regenerate several of the populations of neurons present before injury. notably, ... | 2016 | 27156560 |
| gene expression during the first 28 days of axolotl limb regeneration i: experimental design and global analysis of gene expression. | while it is appreciated that global gene expression analyses can provide novel insights about complex biological processes, experiments are generally insufficiently powered to achieve this goal. here we report the results of a robust microarray experiment of axolotl forelimb regeneration. at each of 20 post-amputation time points, we estimated gene expression for 10 replicate rna samples that were isolated from 1 mm of heterogeneous tissue collected from the distal limb tip. we show that the lim ... | 2015 | 27168937 |
| accessories to limb regeneration. | in a recent issue of nature, nacu et al. (2016) identified fgf and hh ligands as interacting molecular influences that are necessary and sufficient to induce the formation of supernumerary limbs from blastemal tissue in axolotl salamanders. | 2016 | 27219058 |
| cartilage and bone cells do not participate in skeletal regeneration in ambystoma mexicanum limbs. | the mexican axolotl is one of the few tetrapod species that is capable of regenerating complete skeletal elements in injured adult limbs. whether the skeleton (bone and cartilage) plays a role in the patterning and contribution to the skeletal regenerate is currently unresolved. we tested the induction of pattern formation, the effect on cell proliferation, and contributions of skeletal tissues (cartilage, bone, and periosteum) to the regenerating axolotl limb. we found that bone tissue grafts f ... | 2016 | 27316294 |
| neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration. | the mexican axolotl (ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. the molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. an essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in d ... | 2016 | 27317805 |
| could we also be regenerative superheroes, like salamanders? | development of methods to reawaken the semi-dormant regenerative potential that lies within adult human tissues would hold promise for the restoration of diseased or damaged organs and tissues. while most of the regeneration potential is suppressed in many vertebrates, including humans, during adult life, urodele amphibians (salamanders) retain their regenerative ability throughout adulthood. studies in newts and axolotls, two salamander models, have provided significant knowledge about adult li ... | 2016 | 27338874 |
| a conserved microrna regulatory circuit is differentially controlled during limb/appendage regeneration. | although regenerative capacity is evident throughout the animal kingdom, it is not equally distributed throughout evolution. for instance, complex limb/appendage regeneration is muted in mammals but enhanced in amphibians and teleosts. the defining characteristic of limb/appendage regenerative systems is the formation of a dedifferentiated tissue, termed blastema, which serves as the progenitor reservoir for regenerating tissues. in order to identify a genetic signature that accompanies blastema ... | 2016 | 27355827 |
| a concise review of common animal models for the study of limb regeneration. | correct selection of an appropriate animal mode to closely mimic human extremity diseases or to exhibit desirable phenotypes of limb regeneration is the first critical step for all scientists in biomedical and regenerative researches. the commonly-used animals in limb regeneration and repairing studies, such as axolotl, mice, and rats, are discussed in the review and other models including cockroaches, dogs, and horses are also mentioned. the review weighs the general advantages, disadvantages, ... | 2016 | 27391218 |
| fgf and bmp derived from dorsal root ganglia regulate blastema induction in limb regeneration in ambystoma mexicanum. | urodele amphibians have a remarkable organ regeneration ability that is regulated by neural inputs. the identification of these neural inputs has been a challenge. recently, fibroblast growth factor (fgf) and bone morphogenic protein (bmp) were shown to substitute for nerve functions in limb and tail regeneration in urodele amphibians. however, direct evidence of fgf and bmp being secreted from nerve endings and regulating regeneration has not yet been shown. thus, it remained uncertain whether ... | 2016 | 27432514 |
| a histological atlas of the tissues and organs of neotenic and metamorphosed axolotl. | axolotl (ambystoma mexicanum) has been emerging as a promising model in stem cell and regeneration researches due to its exceptional regenerative capacity. although it represents lifelong lasting neoteny, induction to metamorphosis with thyroid hormones (ths) treatment advances the utilization of axolotl in various studies. it has been reported that amphibians undergo anatomical and histological remodeling during metamorphosis and this transformation is crucial for adaptation to terrestrial cond ... | 2016 | 27436816 |
| analysis of embryonic development in the unsequenced axolotl: waves of transcriptomic upheaval and stability. | the axolotl (ambystoma mexicanum) has long been the subject of biological research, primarily owing to its outstanding regenerative capabilities. however, the gene expression programs governing its embryonic development are particularly underexplored, especially when compared to other amphibian model species. therefore, we performed whole transcriptome polya+ rna sequencing experiments on 17 stages of embryonic development. as the axolotl genome is unsequenced and its gene annotation is incomple ... | 2017 | 27475628 |
| myocardial plasticity: cardiac development, regeneration and disease. | the adult mammalian heart is unable to recover from myocardial cell loss due to cardiac ischemia and infarction because terminally differentiated cardiomyocytes proliferate at a low rate. however, cardiomyocytes in other vertebrate animal models such as zebrafish, axolotls, newts and mammalian mouse neonates are capable of de-differentiating in order to promote cardiomyocyte proliferation and subsequent cardiac regeneration after injury. although de-differentiation may occur in adult mammalian c ... | 2016 | 27498024 |
| experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity. | while most tetrapods are unable to regenerate severed body parts, amphibians display a remarkable ability to regenerate an array of structures. frogs can regenerate appendages as larva, but they lose this ability around metamorphosis. in contrast, salamanders regenerate appendages as larva, juveniles, and adults. however, the extent to which fundamental traits (e.g., metamorphosis, body size, aging, etc.) restrict regenerative ability remains contentious. here we utilize the ability of normally ... | 2014 | 27499857 |
| position-specific induction of ectopic limbs in non-regenerating blastemas on axolotl forelimbs. | ectopic retinoic acid (ra) has been hypothesized to reprogram the positional identity of cells in developing and regenerating limbs to a single positional value corresponding to the posterior-ventral-proximal (pvpr) position on the limb. we tested this hypothesis by using ra to reprogram the information of blastema cells that were induced to form at different positions around the limb circumference. we observed that ra treatment of blastemas in anterior and dorsal locations, but not posterior an ... | 2014 | 27499858 |
| ectopic blastema induction by nerve deviation and skin wounding: a new regeneration model in xenopus laevis. | recently, the accessory limb model (alm) has become an alternative study system for limb regeneration studies in axolotls instead of using an amputated limb. alm progresses limb regeneration study in axolotls because of its advantages. to apply and/or to compare knowledge in axolotl alm studies to other vertebrates is a conceivable next step. first, xenopus laevis, an anuran amphibian, was investigated. a xenopus frog has hypomorphic regeneration ability. its regeneration ability has been consid ... | 2014 | 27499859 |
| implication of two different regeneration systems in limb regeneration. | limb regeneration is a representative phenomenon of organ regeneration in urodele amphibians, such as an axolotl. an amputated limb starts regenerating from a remaining stump (proximal) to lost finger tips (distal). in the present case, proximal-distal (pd) reorganization takes place in a regenerating tissue, called a blastema. it has been a mystery how an induced blastema recognizes its position and restores an exact replica of missing parts. recently, a new experimental system called the acces ... | 2014 | 27499860 |
| plasticity for axolotl lens regeneration is associated with age-related changes in gene expression. | mexican axolotls lose potential for lens regeneration 2 weeks after hatching. we used microarrays to identify differently expressed genes before and after this critical time, using rna isolated from iris. over 3700 genes were identified as differentially expressed in response to lentectomy between young (7 days post-hatching) and old (3 months post-hatching) axolotl larvae. strikingly, many of the genes were only expressed in the early or late iris. genes that were highly expressed in young iris ... | 2014 | 27499863 |
| talen-mediated gene editing of the thrombospondin-1 locus in axolotl. | loss-of-function genetics provides strong evidence for a gene's function in a wild-type context. in many model systems, this approach has been invaluable for discovering the function of genes in diverse biological processes. axolotls are urodele amphibians (salamanders) with astonishing regenerative abilities, capable of regenerating entire limbs, portions of the tail (including spinal cord), heart, and brain into adulthood. with their relatively short generation time among salamanders, they off ... | 2015 | 27499866 |
| the axolotl limb blastema: cellular and molecular mechanisms driving blastema formation and limb regeneration in tetrapods. | the axolotl is one of the few tetrapods that are capable of regenerating complicated biological structures, such as complete limbs, throughout adulthood. upon injury the axolotl generates a population of regeneration-competent limb progenitor cells known as the blastema, which will grow, establish pattern, and differentiate into the missing limb structures. in this review we focus on the crucial early events that occur during wound healing, the neural-epithelial interactions that drive the forma ... | 2015 | 27499868 |