photoreception and signal transduction in corals: proteomic and behavioral evidence for cytoplasmic calcium as a mediator of light responsivity.little is known about how corals sense and respond to light. in this report the proteome of coral is explored using 2d protein electrophoresis in two species, montastraea cavernosa and acropora millepora. multiple protein species have major shifts in abundance in both species when sampled in daylight compared to corals sampled late in the night. these changes were observed both in larvae lacking zooxanthellae and in adult tissue containing zooxanthellae, including both pacific and caribbean cora ...201223264475
effects of herbivory, nutrients, and reef protection on algal proliferation and coral growth on a tropical reef.maintaining coral reef resilience against increasing anthropogenic disturbance is critical for effective reef management. resilience is partially determined by how processes, such as herbivory and nutrient supply, affect coral recovery versus macroalgal proliferation following disturbances. however, the relative effects of herbivory versus nutrient enrichment on algal proliferation remain debated. here, we manipulated herbivory and nutrients on a coral-dominated reef protected from fishing, and ...201122038059
Regulation of Bacterial Communities Through Antimicrobial Activity by the Coral Holobiont.Interactions between corals and associated bacteria and amongst these bacterial groups are likely to play a key role in coral health. However, the complexity of these interactions is poorly understood. We investigated the functional role of specific coral-associated bacteria in maintaining microbial communities on the coral Acropora millepora (Ehrenberg 1834) and the ability of coral mucus to support or inhibit bacterial growth. Culture-independent techniques were used to assess bacterial commun ...201121984347
induction of larval metamorphosis of the coral acropora millepora by tetrabromopyrrole isolated from a pseudoalteromonas bacterium.the induction of larval attachment and metamorphosis of benthic marine invertebrates is widely considered to rely on habitat specific cues. while microbial biofilms on marine hard substrates have received considerable attention as specific signals for a wide and phylogenetically diverse array of marine invertebrates, the presumed chemical settlement signals produced by the bacteria have to date not been characterized. here we isolated and fully characterized the first chemical signal from bacter ...201121559509
unexpected complexity of the reef-building coral acropora millepora transcription factor network.abstract:201121526989
validation of housekeeping genes for gene expression studies in symbiodinium exposed to thermal and light stress.unicellular photosynthetic algae (dinoflagellate) from the genus symbiodinium live in mutualistic symbiosis with reef-building corals. cultured symbiodinium sp. (clade c) were exposed to a range of environmental stresses that included elevated temperatures (29°c and 32°c) under high (100 μmol quanta m(-2) s(-1) photosynthetic active radiation) and low (10 μmol quanta m(-2) s(-1)) irradiances. using real-time rt-pcr the stability of expression for the nine selected putative housekeeping genes (hk ...201020668900
construction of a high-resolution genetic linkage map and comparative genome analysis for the reef-building coral acropora millepora.worldwide, coral reefs are in decline due to a range of anthropogenic disturbances, and are now also under threat from global climate change. virtually nothing is currently known about the genetic factors that might determine whether corals adapt to the changing climate or continue to decline. quantitative genetics studies aiming to identify the adaptively important genomic loci will require a high-resolution genetic linkage map. the phylogenetic position of corals also suggests important applic ...200919900279
chimerism in wild adult populations of the broadcast spawning coral acropora millepora on the great barrier reef.chimeras are organisms containing tissues or cells of two or more genetically distinct individuals, and are known to exist in at least nine phyla of protists, plants, and animals. although widespread and common in marine invertebrates, the extent of chimerism in wild populations of reef corals is unknown.200919888471
diversities of coral-associated bacteria differ with location, but not species, for three acroporid corals on the great barrier reef.patterns in the diversity of bacterial communities associated with three species of acropora (acropora millepora, acropora tenuis and acropora valida) were compared at two locations (magnetic island and orpheus island) on the great barrier reef to better understand the nature and specificity of coral-microbial symbioses. three culture-independent techniques demonstrated consistent bacterial communities among replicate samples of each coral species, confirming that corals associate with specific ...200919302548
evidence of an inflammatory-like response in non-normally pigmented tissues of two scleractinian corals.increasing evidence of links between climate change, anthropogenic stress and coral disease underscores the importance of understanding the mechanisms by which reef-building corals resist infection and recover from injury. cellular inflammation and melanin-producing signalling pathway are two mechanisms employed by invertebrates to remove foreign organisms such as pathogens, but they have not been recorded previously in scleractinian corals. this study demonstrates the presence of the phenoloxid ...200818700208
diversity and evolution of coral fluorescent proteins.gfp-like fluorescent proteins (fps) are the key color determinants in reef-building corals (class anthozoa, order scleractinia) and are of considerable interest as potential genetically encoded fluorescent labels. here we report 40 additional members of the gfp family from corals. there are three major paralogous lineages of coral fps. one of them is retained in all sampled coral families and is responsible for the non-fluorescent purple-blue color, while each of the other two evolved a full com ...200818648549
an ancient and variable mannose-binding lectin from the coral acropora millepora binds both pathogens and symbionts.corals form the framework of the world's coral reefs and are under threat from increases in disease and bleaching (symbiotic dysfunction), yet the mechanisms of pathogen and symbiont recognition remain largely unknown. here we describe the isolation and characterisation of an ancient mannose-binding lectin in the coral acropora millepora, which is likely to be involved in both processes. the lectin ('millectin') was isolated by affinity chromatography and was shown to bind to bacterial pathogens ...200818599120
changes in coral-associated microbial communities during a bleaching event.environmental stressors such as increased sea surface temperatures are well-known for contributing to coral bleaching; however, the effect of increased temperatures and subsequent bleaching on coral-associated microbial communities is poorly understood. colonies of the hard coral acropora millepora were tagged on a reef flat off magnetic island (great barrier reef) and surveyed over 2.5 years, which included a severe bleaching event in january/february 2002. daily average water temperatures exce ...200818059490
apparent involvement of a beta1 type integrin in coral fertilization.integrins are involved in a wide variety of cell adhesion processes, and have roles in gamete binding and fusion in mammals. integrins have been also discovered in the scleractinian coral acropora millepora (cnidaria: anthozoa). as a first step toward understanding the molecular basis of fertilization in corals, we examined the effect of polyclonal antisera raised against recombinant coral integrins on gamete interactions in a. millepora. antiserum raised against integrin betacn1 dramatically de ...200717694414
immunohistochemical localization of a retinoic acid-like receptor in nerve cells of two colonial anthozoans (cnidaria).retinoic acid is known to induce vertebrate stem cells to differentiate into a variety of cell types, including neurons. although retinoic acid was reported to affect morphogenetic pattern specification in the hydrozoan hydractinia (müller, w.a., 1984. retinoids and pattern formation in a hydroid. j. embryol. exp. morph. 81, 253-271) and a retinoid rxr receptor was cloned in the jellyfish tripedalia (kostrouch, z., kostrouchova, m., love, w., jannini, e., piatigorsky, j., rall, j.e., 1998. retin ...200717376496
the role of zooxanthellae in the thermal tolerance of corals: a 'nugget of hope' for coral reefs in an era of climate change.the ability of coral reefs to survive the projected increases in temperature due to global warming will depend largely on the ability of corals to adapt or acclimatize to increased temperature extremes over the next few decades. many coral species are highly sensitive to temperature stress and the number of stress (bleaching) episodes has increased in recent decades. we investigated the acclimatization potential of acropora millepora, a common and widespread indo-pacific hard coral species, thro ...200616928632
snail expression during embryonic development of the coral acropora: blurring the diploblast/triploblast divide?although corals are nominally diploblastic, the early development of acropora millepora involves a process that clearly resembles gastrulation in higher metazoans. this similarity at the morphological level led us to search for the acropora equivalents of genes whose key roles in gastrulation are conserved across the higher metazoa. we here report the characterisation of one such gene, snail, which in both drosophila and the mouse is expressed in cells undergoing an epithelial-mesenchyme transit ...200415029498
coral-associated bacteria and their role in the biogeochemical cycling of sulfur.marine bacteria play a central role in the degradation of dimethylsulfoniopropionate (dmsp) to dimethyl sulfide (dms) and acrylic acid, dms being critical to cloud formation and thereby cooling effects on the climate. high concentrations of dmsp and dms have been reported in scleractinian coral tissues although, to date, there have been no investigations into the influence of these organic sulfur compounds on coral-associated bacteria. two coral species, montipora aequituberculata and acropora m ...200919346350
predicting water toxicity: pairing passive sampling with bioassays on the great barrier reef.many coral reefs worldwide occur adjacent to urban or agricultural land which places these ecosystems at threat of exposure to complex mixtures of pollutants. in this study, the pairing of passive sampler extracts with bioassays is proposed as a tool for predicting effects of organic pollutant mixtures on key biota within coral reef ecosystems. passive samplers, sdb-rps empore disks, which sequester a mixture of the contaminants present in the environment, were deployed at three sites in the gre ...200919819564
sequencing and de novo analysis of a coral larval transcriptome using 454 methods are needed for genomic-scale analysis of emerging model organisms that exemplify important biological questions but lack fully sequenced genomes. for example, there is an urgent need to understand the potential for corals to adapt to climate change, but few molecular resources are available for studying these processes in reef-building corals. to facilitate genomics studies in corals and other non-model systems, we describe methods for transcriptome sequencing using 454, as well as s ...200919435504
est analysis of the cnidarian acropora millepora reveals extensive gene loss and rapid sequence divergence in the model invertebrates.a significant proportion of mammalian genes are not represented in the genomes of drosophila, caenorhabditis or saccharomyces, and many of these are assumed to have been vertebrate innovations. to test this assumption, we conducted a preliminary est project on the anthozoan cnidarian, acropora millepora, a basal metazoan. more than 10% of the acropora ests with strong metazoan matches to the databases had clear human homologs but were not represented in the drosophila or caenorhabditis genomes; ...200314680636
gene expression profiles of cytosolic heat shock proteins hsp70 and hsp90 from symbiotic dinoflagellates in response to thermal stress: possible implications for coral bleaching.unicellular photosynthetic dinoflagellates of the genus symbiodinium are the most common endosymbionts of reef-building scleractinian corals, living in a symbiotic partnership known to be highly susceptible to environmental changes such as hyperthermic stress. in this study, we identified members of two major heat shock proteins (hsps) families, hsp70 and hsp90, in symbiodinium sp. (clade c) with full-length sequences that showed the highest similarity and evolutionary relationship with other kn ...201120821176
transcriptional activation of c3 and hsp70 as part of the immune response of acropora millepora to bacterial challenges.the impact of disease outbreaks on coral physiology represents an increasing concern for the fitness and resilience of reef ecosystems. predicting the tolerance of corals to disease relies on an understanding of the coral immune response to pathogenic interactions. this study explored the transcriptional response of two putative immune genes (c3 and c-type lectin) and one stress response gene (hsp70) in the reef building coral, acropora millepora challenged for 48 hours with bacterial strains, v ...201323861754
the acute transcriptional response of the coral acropora millepora to immune challenge: expression of gimap/ian genes links the innate immune responses of corals with those of mammals and a step towards understanding coral immunity we present the first whole transcriptome analysis of the acute responses of acropora millepora to challenge with the bacterial cell wall derivative mdp and the viral mimic poly i:c, defined immunogens provoking distinct but well characterised responses in higher animals.201323768317
differential regulation by heat stress of novel cytochrome p450 genes from the dinoflagellate symbionts of reef-building corals.exposure to heat stress has been recognized as one of the major factors leading to the breakdown of the coral-alga symbiosis and coral bleaching. here, we describe the presence of three new cytochrome p450 (cyp) genes from the reef-building coral endosymbiont symbiodinium (type c3) and changes in their expression during exposure to severe and moderate heat stress conditions. sequence analysis of the cyp c-terminal region and two conserved domains, the "perf" and "heme-binding" domains, confirmed ...201020228102
corals form characteristic associations with symbiotic nitrogen-fixing bacteria.the complex symbiotic relationship between corals and their dinoflagellate partner symbiodinium is believed to be sustained through close associations with mutualistic bacterial communities, though little is known about coral associations with bacterial groups able to fix nitrogen (diazotrophs). in this study, we investigated the diversity of diazotrophic bacterial communities associated with three common coral species (acropora millepora, acropora muricata, and pocillopora damicormis) from thre ...201222344646
differential coral bleaching-contrasting the activity and response of enzymatic antioxidants in symbiotic partners under thermal stress.mass coral bleaching due to thermal stress represents a major threat to the integrity and functioning of coral reefs. thermal thresholds vary, however, between corals, partly as a result of the specific type of endosymbiotic dinoflagellate (symbiodinium sp.) they harbour. the production of reactive oxygen species (ros) in corals under thermal and light stress has been recognised as one mechanism that can lead to cellular damage and the loss of their symbiont population (oxidative theory of coral ...201526310104
characterization of a group of mites with unusual features from two coral genomes.miniature inverted-repeat transposable elements (mites), which are common in eukaryotic genomes, are small non-coding elements that transpose by utilizing transposases encoded by autonomous transposons. recent genome-wide analyses and cross-mobilization assays have greatly improved our knowledge on mite proliferation, however, specific mechanisms for the origin and evolution of mites are still unclear.201020502527
larval settlement: the role of surface topography for sessile coral reef invertebrates.for sessile marine invertebrates with complex life cycles, habitat choice is directed by the larval phase. defining which habitat-linked cues are implicated in sessile invertebrate larval settlement has largely concentrated on chemical cues which are thought to signal optimal habitat. there has been less effort establishing physical settlement cues, including the role of surface microtopography. this laboratory based study tested whether surface microtopography alone (without chemical cues) play ...201525671562
impacts of turbidity on corals: the relative importance of light limitation and suspended part of an investigation of the effects of water quality from dredging/natural resuspension on reefs, the effects of suspended sediment concentrations (sscs) (0, 30, 100mgl(-1)) and light (~0, 1.1, 8.6molphotonsm(-2)d(-1)) were examined alone and in combination, on the corals acropora millepora, montipora capricornis and porites spp. over an extended (28d) period. no effects were observed at any sediment concentrations when applied alone. all corals in the lowest light treatments lost chlorop ...201728162249
recovery from bleaching is mediated by threshold densities of background thermo-tolerant symbiont types in a reef-building coral.sensitive molecular analyses show that most corals host a complement of symbiodinium genotypes that includes thermo-tolerant types in low abundance. while tolerant symbiont types are hypothesized to facilitate tolerance to temperature and recovery from bleaching, empirical data on their distribution and relative abundance in corals under ambient and stress conditions are still rare. we quantified visual bleaching and mortality of coral hosts, along with relative abundance of c- and d-type symbio ...201627429786
genetic markers for antioxidant capacity in a reef-building coral.the current lack of understanding of the genetic basis underlying environmental stress tolerance in reef-building corals impairs the development of new management approaches to confronting the global demise of coral reefs. on the great barrier reef (gbr), an approximately 51% decline in coral cover occurred over the period 1985-2012. we conducted a gene-by-environment association analysis across 12° latitude on the gbr, as well as both in situ and laboratory genotype-by-phenotype association ana ...201627386515
lunar phase modulates circadian gene expression cycles in the broadcast spawning coral acropora millepora.many broadcast spawning corals in multiple reef regions release their gametes with incredible temporal precision just once per year, using the lunar cycle to set the night of spawning. moonlight, rather than tides or other lunar-regulated processes, is thought to be the proximate factor responsible for linking the night of spawning to the phase of the moon. we compared patterns of gene expression among colonies of the broadcast spawning coral acropora millepora at different phases of the lunar c ...201627132135
congruent patterns of connectivity can inform management for broadcast spawning corals on the great barrier reef.connectivity underpins the persistence and recovery of marine ecosystems. the great barrier reef (gbr) is the world's largest coral reef ecosystem and managed by an extensive network of no-take zones; however, information about connectivity was not available to optimize the network's configuration. we use multivariate analyses, bayesian clustering algorithms and assignment tests of the largest population genetic data set for any organism on the gbr to date (acropora tenuis, >2500 colonies; >50 r ...201627085309
gene expression of corals in response to macroalgal corals decline and macroalgae proliferate on coral reefs, coral-macroalgal competition becomes more frequent and ecologically important. whether corals are damaged by these interactions depends on susceptibility of the coral and traits of macroalgal competitors. investigating changes in gene expression of corals and their intracellular symbiotic algae, symbiodinium, in response to contact with different macroalgae provides insight into the biological processes and cellular pathways affected b ...201425500576
effects of high dissolved inorganic and organic carbon availability on the physiology of the hard coral acropora millepora from the great barrier reef.coral reefs are facing major global and local threats due to climate change-induced increases in dissolved inorganic carbon (dic) and because of land-derived increases in organic and inorganic nutrients. recent research revealed that high availability of labile dissolved organic carbon (doc) negatively affects scleractinian corals. studies on the interplay of these factors, however, are lacking, but urgently needed to understand coral reef functioning under present and near future conditions. th ...201626959499
a comparative view of early development in the corals favia lizardensis, ctenactis echinata, and acropora millepora - morphology, transcriptome, and developmental gene expression.research into various aspects of coral biology has greatly increased in recent years due to anthropogenic threats to coral health including pollution, ocean warming and acidification. however, knowledge of coral early development has lagged. the present paper describes the embryonic development of two previously uncharacterized robust corals, favia lizardensis (a massive brain coral) and ctenactis echinata (a solitary coral) and compares it to that of the previously characterized complex coral, ...201626924819
sequence and expression of four coral g protein-coupled receptors distinct from all classifiable members of the rhodopsin family.a measure of the functional importance of g protein-coupled receptors (gpcrs) as signalling molecules is that over seven hundred have been cloned and identified in the human genome alone. yet few have been characterized in the lower metazoan phyla, especially in the phylum cnidaria which is well positioned phylogenetically for tracing the early evolution of gpcrs owing to their possession of the first-evolved nervous systems. we report here the cloning and characterization of four novel rhodopsi ...200717196770
host coenzyme q redox state is an early biomarker of thermal stress in the coral acropora millepora.bleaching episodes caused by increasing seawater temperatures may induce mass coral mortality and are regarded as one of the biggest threats to coral reef ecosystems worldwide. the current consensus is that this phenomenon results from enhanced production of harmful reactive oxygen species (ros) that disrupt the symbiosis between corals and their endosymbiotic dinoflagellates, symbiodinium. here, the responses of two important antioxidant defence components, the host coenzyme q (coq) and symbion ...201526426118
expression of calcification and metabolism-related genes in response to elevated pco2 and temperature in the reef-building coral acropora millepora.declining health of scleractinian corals in response to deteriorating environmental conditions is widely acknowledged, however links between physiological and functional genomic responses of corals are less well understood. here we explore growth and the expression of 20 target genes with putative roles in metabolism and calcification in the branching coral, acropora millepora, in two separate experiments: 1) elevated pco2 (464, 822, 1187 and 1638 μatm) and ambient temperature (27°c), and 2) ele ...201526275825
a population genetic assessment of coral recovery on highly disturbed reefs of the keppel island archipelago in the southern great barrier reef.coral reefs surrounding the islands lying close to the coast are unique to the great barrier reef (gbr) in that they are frequently exposed to disturbance events including floods caused by cyclonic rainfall, strong winds and occasional periods of prolonged above-average temperatures during summer. in one such group of islands in the southern gbr, the keppel island archipelago, climate-driven disturbances frequently result in major coral mortality. whilst these island reefs have clearly survived ...201526244109
transcriptomic differences between day and night in acropora millepora provide new insights into metabolite exchange and light-enhanced calcification in corals.the evolutionary success of reef-building corals is often attributed to their symbiotic relationship with photosynthetic dinoflagellates of the genus symbiodinium, but metabolic interactions between the partners and the molecular bases of light-enhanced calcification (lec) are not well understood. here, the metabolic bases of the interaction between the coral acropora millepora and its dinoflagellate symbiont were investigated by comparing gene expression levels under light and dark conditions a ...201526198296
profiling molecular and behavioral circadian rhythms in the non-symbiotic sea anemone nematostella vectensis.endogenous circadian clocks are poorly understood within early-diverging animal lineages. we have characterized circadian behavioral patterns and identified potential components of the circadian clock in the starlet sea anemone, nematostella vectensis: a model cnidarian which lacks algal symbionts. using automatic video tracking we showed that nematostella exhibits rhythmic circadian locomotor activity, which is persistent in constant dark, shifted or disrupted by external dark/light cues and ma ...201526081482
quantitative high resolution melting: two methods to determine snp allele frequencies from pooled samples.the advent of next-generation sequencing has brought about an explosion of single nucleotide polymorphism (snp) data in non-model organisms; however, profiling these snps across multiple natural populations still requires substantial time and resources.201526070466
physiological and ecological performance differs in four coral taxa at a volcanic carbon dioxide seep.around volcanic carbon dioxide (co2) seeps in papua new guinea, partial pressures of co2 (pco2) approximate those as predicted for the end of this century, and coral communities have low diversity and low structural complexity. to assess the mechanisms for such community shifts in response to ocean acidification, we examined the physiological performance of two hard corals that occur with increased or unaltered abundance at a seep site (mean phtotal=7.8, pco2=862 μatm) compared to a control site ...201525727938
highly heterogeneous bacterial communities associated with the south china sea reef corals porites lutea, galaxea fascicularis and acropora millepora.coral harbor diverse and specific bacteria play significant roles in coral holobiont function. bacteria associated with three of the common and phylogenetically divergent reef-building corals in the south china sea, porites lutea, galaxea fascicularis and acropora millepora, were investigated using 454 barcoded-pyrosequencing. three colonies of each species were sampled, and 16s rrna gene libraries were constructed individually. analysis of pyrosequencing libraries showed that bacterial communit ...201323940737
the organizer in evolution-gastrulation and organizer gene expression highlight the importance of brachyury during development of the coral, acropora millepora.organizer activity, once thought to be restricted to vertebrates, has ancient origins. however, among non-bilaterians, it has only been subjected to detailed investigation during embryonic development of the sea anemone, nematostella vectensis. as a step toward establishing the extent to which findings in nematostella can be generalized across the large and diverse phylum cnidaria, we examined the expression of some key organizer and gastrulation genes during the embryonic development of the cor ...201525601451
symbiodinium identity alters the temperature-dependent settlement behaviour of acropora millepora coral larvae before the onset of symbiosis.the global distribution of marine species, many of which disperse during the larval stages, is influenced by ocean temperature regimes. here, we test how temperature and the coral symbionts (symbiodinium) affect survival, symbiont uptake, settlement success and habitat choice of acropora millepora larvae. experiments were conducted at heron island (australia), where larvae were exposed to 22.5, 24.5, 26.5 and 28.5°c. within each temperature treatment, larvae were offered symbionts with distinct ...201525589607
integrins of the starlet sea anemone nematostella vectensis.integrins are extracellular matrix receptors composed of α and β subunits. here we describe two α subunits and four β subunits from the starlet sea anemone nematostella vectensis. phylogenetic analysis suggests that the α subunits are most closely related to rgd- and ldv-dependent α subunits of chordates. the β subunits cluster with the previously described β integrins of the hard coral acropora millepora. the expression of one of the α subunits and three of the β subunits was confirmed by rever ...201425572209
comparative immune responses of corals to stressors associated with offshore reef-based tourist platforms.unravelling the contributions of local anthropogenic and seasonal environmental factors in suppressing the coral immune system is important for prioritizing management actions at reefs exposed to high levels of human activities. here, we monitor health of the model coral acropora millepora adjacent to a high-use and an unused reef-based tourist platform, plus a nearby control site without a platform, over 7 months spanning a typical austral summer. comparisons of temporal patterns in a range of ...201527293717
bimodal signatures of germline methylation are linked with gene expression plasticity in the coral acropora invertebrates, genes belonging to dynamically regulated functional categories appear to be less methylated than "housekeeping" genes, suggesting that dna methylation may modulate gene expression plasticity. to date, however, experimental evidence to support this hypothesis across different natural habitats has been lacking.201425511458
dimethylsulfoniopropionate, superoxide dismutase and glutathione as stress response indicators in three corals under short-term hyposalinity stress.corals are among the most active producers of dimethylsulfoniopropionate (dmsp), a key molecule in marine sulfur cycling, yet the specific physiological role of dmsp in corals remains elusive. here, we examine the oxidative stress response of three coral species (acropora millepora, stylophora pistillata and pocillopora damicornis) and explore the antioxidant role of dmsp and its breakdown products under short-term hyposalinity stress. symbiont photosynthetic activity declined with hyposalinity ...201626865302
functional conservation of the apoptotic machinery from coral to man: the diverse and complex bcl-2 and caspase repertoires of acropora millepora.apoptotic cell death is a defining and ubiquitous characteristic of metazoans, but its evolutionary origins are unclear. although caenorhabditis and drosophila played key roles in establishing the molecular bases of apoptosis, it is now clear that cell death pathways of these animals do not reflect ancestral characteristics. conversely, recent work suggests that the apoptotic networks of cnidarians may be complex and vertebrate-like, hence characterization of the apoptotic complement of represen ...201626772977
host-associated coral reef microbes respond to the cumulative pressures of ocean warming and ocean acidification.key calcifying reef taxa are currently threatened by thermal stress associated with elevated sea surface temperatures (sst) and reduced calcification linked to ocean acidification (oa). here we undertook an 8 week experimental exposure to near-future climate change conditions and explored the microbiome response of the corals acropora millepora and seriatopora hystrix, the crustose coralline algae hydrolithon onkodes, the foraminifera marginopora vertebralis and heterostegina depressa and the se ...201626758800
imaging the uptake of nitrogen-fixing bacteria into larvae of the coral acropora millepora.diazotrophic bacteria are instrumental in generating biologically usable forms of nitrogen by converting abundant dinitrogen gas (n2) into available forms, such as ammonium. although nitrogen is crucial for coral growth, direct observation of associations between diazotrophs and corals has previously been elusive. we applied fluorescence in situ hybridization (fish) and nanoscale secondary ion mass spectrometry to observe the uptake of (15)n-enriched diazotrophic vibrio sp. isolated from acropor ...201626696324
physiological response to elevated temperature and pco2 varies across four pacific coral species: understanding the unique host+symbiont response.the physiological response to individual and combined stressors of elevated temperature and pco2 were measured over a 24-day period in four pacific corals and their respective symbionts (acropora millepora/symbiodinium c21a, pocillopora damicornis/symbiodinium c1c-d-t, montipora monasteriata/symbiodinium c15, and turbinaria reniformis/symbiodinium trenchii). multivariate analyses indicated that elevated temperature played a greater role in altering physiological response, with the greatest degre ...201526670946
red fluorescence in coral larvae is associated with a diapause-like state.effective dispersal across environmental gradients is the key to species resilience to environmental perturbation, including climate change. coral reefs are among the most sensitive ecosystems to global warming, but factors predicting coral dispersal potential remain unknown. in a reef-building coral acropora millepora, larval fluorescence emerged as a possible indicator of dispersal potential since it correlates with responsiveness to a settlement cue. here, we show that gene expression in red ...201626600127
expression of putative immune response genes during early ontogeny in the coral acropora millepora.corals, like many other marine invertebrates, lack a mature allorecognition system in early life history stages. indeed, in early ontogeny, when corals acquire and establish associations with various surface microbiota and dinoflagellate endosymbionts, they do not efficiently distinguish between closely and distantly related individuals from the same population. however, very little is known about the molecular components that underpin allorecognition and immunity responses or how they change th ...201222792163
differential responses of coral larvae to the colour of ambient light guide them to suitable settlement microhabitat.reef-building corals produce planktonic planula larvae that must select an appropriate habitat to settle and spend the rest of their life, a behaviour that plays a critical role in survival. here, we report that larvae obtained from a deep-water population of pseudodiploria strigosa settled more readily under blue light and in the dark, which aligns well with the light field characteristics of their natal habitat. by contrast, larvae of the shallow-water coral acropora millepora settled in high ...201526587247
distribution and evolution of the serine/aspartate racemase family in d-amino acids have been found in various invertebrate phyla, while amino acid racemase genes have been identified in few species. the purpose of this study is to elucidate the distribution, function, and evolution of amino acid racemases in invertebrate animals. we searched the genbank databases, and found 11 homologous serine racemase genes from eight species in eight different invertebrate phyla. the cloned genes were identified based on their maximum activity as acropora millepora (cnida ...201626352274
mutational analysis of the acropora millepora paxd paired domain highlights the importance of the linker region for dna binding.pax transcription factors are found in animals, from simple sponges to insects and vertebrates. the defining feature of pax proteins is the dna-binding paired domain (pd), which consists of two helix-turn-helix subdomains, joined with a linker region. despite high specificity in vivo, the paired domains of different pax proteins bind similar consensus dna sequences in vitro. using bandshift techniques, we show here that the paired domain of the acropora millepora paxd protein, which unambiguousl ...200314597391
natural volcanic co2 seeps reveal future trajectories for host-microbial associations in corals and sponges.atmospheric carbon dioxide (co2) levels are rapidly rising causing an increase in the partial pressure of co2 (pco2) in the ocean and a reduction in ph known as ocean acidification (oa). natural volcanic seeps in papua new guinea expel 99% pure co2 and thereby offer a unique opportunity to explore the effects of oa in situ. the corals acropora millepora and porites cylindrica were less abundant and hosted significantly different microbial communities at the co2 seep than at nearby control sites ...201425325380
transcriptomic changes in coral holobionts provide insights into physiological challenges of future climate and ocean change.tropical reef-building coral stress levels will intensify with the predicted rising atmospheric co2 resulting in ocean temperature and acidification increase. most studies to date have focused on the destabilization of coral-dinoflagellate symbioses due to warming oceans, or declining calcification due to ocean acidification. in our study, ph and temperature conditions consistent with the end-of-century scenarios of the intergovernmental panel on climate change (ipcc) caused major changes in pho ...201526510159
coral calcification under daily oxygen saturation and ph dynamics reveals the important role of oxygen.coral reefs are essential to many nations, and are currently in global decline. although climate models predict decreases in seawater ph (∼0.3 units) and oxygen saturation (∼5 percentage points), these are exceeded by the current daily ph and oxygen fluctuations on many reefs (ph 7.8-8.7 and 27-241% o2 saturation). we investigated the effect of oxygen and ph fluctuations on coral calcification in the laboratory using the model species acropora millepora. light calcification rates were greatly en ...201424857847
discovery of a strongly-interrelated gene network in corals under constant darkness by correlation analysis after wavelet transform on complex network model.coral reefs occupy a relatively small portion of sea area, yet serve as a crucial source of biodiversity by establishing harmonious ecosystems with marine plants and animals. previous researches mainly focused on screening several key genes induced by stress. here we proposed a novel method--correlation analysis after wavelet transform of complex network model, to explore the effect of light on gene expression in the coral acropora millepora based on microarray data. in this method, wavelet tran ...201424651851
gene expression patterns during the early stages of chemically induced larval metamorphosis and settlement of the coral acropora millepora.the morphogenetic transition of motile coral larvae into sessile primary polyps is triggered and genetically programmed upon exposure to environmental biomaterials, such as crustose coralline algae (cca) and bacterial biofilms. although the specific chemical cues that trigger coral larval morphogenesis are poorly understood there is much more information available on the genes that play a role in this early life phase. putative chemical cues from natural biomaterials yielded defined chemical sam ...201424632854
corals like it waxed: paraffin-based antifouling technology enhances coral spat survival.the early post-settlement stage is the most sensitive during the life history of reef building corals. however, few studies have examined the factors that influence coral mortality during this period. here, the impact of fouling on the survival of newly settled coral spat of acropora millepora was investigated by manipulating the extent of fouling cover on settlement tiles using non-toxic, wax antifouling coatings. survival of spat on coated tiles was double that on control tiles. moreover, ther ...201424489936
amplicon pyrosequencing reveals spatial and temporal consistency in diazotroph assemblages of the acropora millepora microbiome.diazotrophic bacteria potentially play an important functional role in supplying fixed nitrogen to the coral holobiont, but the value of such a partnership depends on the stability of the association. here we evaluate the composition of diazotroph assemblages associated with the coral acropora millepora throughout four seasons and at two reefs, an inshore and an offshore (mid-shelf) reef on the great barrier reef, australia. amplicon pyrosequencing of the nifh gene revealed that diazotrophs are ...201424373029
coral energy reserves and calcification in a high-co2 world at two temperatures.rising atmospheric co2 concentrations threaten coral reefs globally by causing ocean acidification (oa) and warming. yet, the combined effects of elevated pco2 and temperature on coral physiology and resilience remain poorly understood. while coral calcification and energy reserves are important health indicators, no studies to date have measured energy reserve pools (i.e., lipid, protein, and carbohydrate) together with calcification under oa conditions under different temperature scenarios. fo ...201324146747
reduced salinity decreases the fertilization success and larval survival of two scleractinian coral species.successful reproduction by scleractinian corals is essential for the maintenance of populations that form the foundation of coral reef ecosystems. laboratory experiments were done to determine the effects of reduced salinity on the fertilization success and larval survival of two coral species, platygyra daedalea and acropora millepora, from the great barrier reef, australia. fertilization rates of p. daedalea and a. millepora were significantly reduced at 25.8 psu and 33.1 psu, respectively, an ...201324008005
gene expression patterns of the coral acropora millepora in response to contact with with macroalgae often causes coral mortality, but the roles of abrasion versus shading versus allelopathy in these interactions are rarely clear and effects on gene expression are unknown. identification of gene expression changes within corals in response to contact with macroalgae can provide insight into the mode of action of allelochemicals, as well as reveal transcriptional strategies of the coral that mitigate damage from this competitive interaction, enabling the coral to survive. ...201223997654
historical and contemporary factors shape the population genetic structure of the broadcast spawning coral, acropora millepora, on the great barrier reef.effective management of reef corals requires knowledge of the extent to which populations are open or closed and the scales over which genetic exchange occurs, information which is commonly derived from population genetic data. such data are sparse for great barrier reef (gbr) corals and other organisms, with the studies that are available being mostly based on a small number of sampling locations spanning only part of the gbr. using 11 microsatellite loci, we genotyped 947 colonies of the reef- ...201122026459
resistance to thermal stress in corals without changes in symbiont composition.discovering how corals can adjust their thermal sensitivity in the context of global climate change is important in understanding the long-term persistence of coral reefs. in this study, we showed that short-term preconditioning to higher temperatures, 3°c below the experimentally determined bleaching threshold, for a period of 10 days provides thermal tolerance for the symbiosis stability between the scleractinian coral, acropora millepora and symbiodinium. based on genotypic analysis, our resu ...201221976690
historical thermal regimes define limits to coral acclimatization.knowledge of the degree to which corals undergo physiological acclimatization or genetic adaptation in response to changes in their thermal environment is crucial to the success of coral reef conservation strategies. the potential of corals to acclimatize to temperatures exceeding historical thermal regimes was investigated by reciprocal transplantation of acropora millepora colonies between the warm central and cool southern regions of the great barrier reef (gbr) for a duration of 14 months. c ...201323858648
profiling gene expression responses of coral larvae (acropora millepora) to elevated temperature and settlement inducers using a novel rna-seq procedure.elevated temperatures resulting from climate change pose a clear threat to reef-building corals; however, the traits that might influence corals' survival and dispersal during climate change remain poorly understood. global gene expression profiling is a powerful hypothesis-forming tool that can help elucidate these traits. here, we applied a novel rna-seq protocol to study molecular responses to heat and settlement inducers in aposymbiotic larvae of the reef-building coral acropora millepora. t ...201121801258
the skeletal proteome of the coral acropora millepora: the evolution of calcification by co-option and domain corals, biocalcification is a major function that may be drastically affected by ocean acidification (oa). scleractinian corals grow by building up aragonitic exoskeletons that provide support and protection for soft tissues. although this process has been extensively studied, the molecular basis of biocalcification is poorly understood. notably lacking is a comprehensive catalog of the skeleton-occluded proteins-the skeletal organic matrix proteins (somps) that are thought to regulate the mi ...201323765379
rapid evolution of coral proteins responsible for interaction with the environment.corals worldwide are in decline due to climate change effects (e.g., rising seawater temperatures), pollution, and exploitation. the ability of corals to cope with these stressors in the long run depends on the evolvability of the underlying genetic networks and proteins, which remain largely unknown. a genome-wide scan for positively selected genes between related coral species can help to narrow down the search space considerably.201121633702
a comparative study of phenoloxidase activity in diseased and bleached colonies of the coral acropora scleractinian (hard) corals, immune responses involving phenoloxidase (po) activity are known to play a role in coral wound healing, but there have been no studies investigating their roles in mitigating either disease or bleaching in an indo-pacific coral. po activity induces the release of reactive oxygen species leading to a cytotoxic cellular environment, which enhances resistance against pathogens, but is also likely to compound oxidative stress induced during bleaching. antioxidants suc ...201121527282
spatial and temporal genetic structure of symbiodinium populations within a common reef-building coral on the great barrier reef.the dinoflagellate photosymbiont symbiodinium plays a fundamental role in defining the physiological tolerances of coral holobionts, but little is known about the dynamics of these endosymbiotic populations on coral reefs. sparse data indicate that symbiodinium populations show limited spatial connectivity; however, no studies have investigated temporal dynamics for in hospite symbiodinium populations following significant mortality and recruitment events in coral populations. we investigated th ...201323730715
gene expression signatures of energetic acclimatisation in the reef building coral acropora millepora.understanding the mechanisms by which natural populations cope with environmental stress is paramount to predict their persistence in the face of escalating anthropogenic impacts. reef-building corals are increasingly exposed to local and global stressors that alter nutritional status causing reduced fitness and mortality, however, these responses can vary considerably across species and populations.201323671571
high natural gene expression variation in the reef-building coral acropora millepora: potential for acclimative and adaptive plasticity.ecosystems worldwide are suffering the consequences of anthropogenic impact. the diverse ecosystem of coral reefs, for example, are globally threatened by increases in sea surface temperatures due to global warming. studies to date have focused on determining genetic diversity, the sequence variability of genes in a species, as a proxy to estimate and predict the potential adaptive response of coral populations to environmental changes linked to climate changes. however, the examination of natur ...201323565725
the neuronal calcium sensor protein acrocalcin: a potential target of calmodulin regulation during development in the coral acropora understand the calcium-mediated signalling pathways underlying settlement and metamorphosis in the scleractinian coral acropora millepora, a predicted protein set derived from larval cdnas was scanned for the presence of ef-hand domains (pfam id: pf00036). this approach led to the identification of a canonical calmodulin (amcam) protein and an uncharacterised member of the neuronal calcium sensor (ncs) family of proteins known here as acrocalcin (amac). while amcam transcripts were present th ...201223284743
detection of polyketide synthase and nonribosomal peptide synthetase biosynthetic genes from antimicrobial coral-associated actinomycetes.the diversity and properties of actinobacteria, predominant residents in coral holobionts, have been rarely documented. in this study, we aimed to explore the species diversity, antimicrobial activities and biosynthetic potential of culturable actinomycetes within the tissues of the scleractinian corals porites lutea, galaxea fascicularis and acropora millepora from the south china sea. a total of 70 strains representing 13 families and 15 genera of actinobacteria were isolated. the antimicrobia ...201425190333
the n-terminal intrinsically disordered domain of mgm101p is localized to the mitochondrial nucleoid.the mitochondrial genome maintenance gene, mgm101, is essential for yeasts that depend on mitochondrial dna replication. previously, in saccharomyces cerevisiae, it has been found that the carboxy-terminal two-thirds of mgm101p has a functional core. furthermore, there is a high level of amino acid sequence conservation in this region from widely diverse species. by contrast, the amino-terminal region, that is also essential for function, does not have recognizable conservation. using a bioinfor ...201323418572
chemical and physical environmental conditions underneath mat- and canopy-forming macroalgae, and their effects on understorey corals.disturbed coral reefs are often dominated by dense mat- or canopy-forming assemblages of macroalgae. this study investigated how such dense macroalgal assemblages change the chemical and physical microenvironment for understorey corals, and how the altered environmental conditions affect the physiological performance of corals. field measurements were conducted on macroalgal-dominated inshore reefs in the great barrier reef in quadrats with macroalgal biomass ranging from 235 to 1029 g dw m(-2) ...201020856882
fluorescent protein-mediated colour polymorphism in reef corals: multicopy genes extend the adaptation/acclimatization potential to variable light environments.the genomic framework that enables corals to adjust to unfavourable conditions is crucial for coral reef survival in a rapidly changing climate. we have explored the striking intraspecific variability in the expression of coral pigments from the green fluorescent protein (gfp) family to elucidate the genomic basis for the plasticity of stress responses among reef corals. we show that multicopy genes can greatly increase the dynamic range over which corals can modulate transcript levels in respon ...201525496144
rapid acclimation of juvenile corals to co2 -mediated acidification by upregulation of heat shock protein and bcl-2 genes.corals play a key role in ocean ecosystems and carbonate balance, but their molecular response to ocean acidification remains unclear. the only previous whole-transcriptome study (moya et al. molecular ecology, 2012; 21, 2440) documented extensive disruption of gene expression, particularly of genes encoding skeletal organic matrix proteins, in juvenile corals (acropora millepora) after short-term (3 d) exposure to elevated pco2 . in this study, whole-transcriptome analysis was used to compare t ...201525444080
characterisation of nitric oxide synthase in three cnidarian-dinoflagellate symbioses.nitric oxide synthase (nos) is an enzyme catalysing the conversion of l-arginine to l-citrulline and nitric oxide (no), the latter being an essential messenger molecule for a range of biological processes. whilst its role in higher vertebrates is well understood little is known about the role of this enzyme in early metazoan groups. for instance, nos-mediated signalling has been associated with cnidaria-algal symbioses, however controversy remains about the contribution of enzyme activities by t ...201020442851
onset and establishment of diazotrophs and other bacterial associates in the early life history stages of the coral acropora millepora.early establishment of coral-microbial symbioses is fundamental to the fitness of corals, but comparatively little is known about the onset and succession of bacterial communities in their early life history stages. in this study, bacterial associates of the coral acropora millepora were characterized throughout the first year of life, from larvae and 1-week-old juveniles reared in laboratory conditions in the absence of the dinoflagellate endosymbiont symbiodinium to field-outplanted juveniles ...201425156176
genotype - environment correlations in corals from the great barrier reef.knowledge of genetic markers that are correlated to stress tolerance may improve spatial mapping of reef vulnerability and can inform restoration efforts, including the choice of genotypes for breeding and reseeding. in this manuscript we present two methods for screening transcriptome data for candidate genetic markers in two reef building corals, acropora millepora and pocillopora damicornis (types α and β). in a. millepora, single nucleotide polymorphisms (snps) were pre-selected by targeting ...201323433436
does trophic status enhance or reduce the thermal tolerance of scleractinian corals? a review, experiment and conceptual warming, and nutrient and sediment runoff from coastal development, both exert increasing pressures on coastal coral reefs. the objective of this study was to resolve the question of whether coastal eutrophication may protect corals from thermal stress by improving their nutritional status, or rather diminish their thermal tolerance through the synergy of dual stressors. a review of previous studies on the topic of combined trophic status and heat exposure on the thermal tolerance of cora ...201323349876
coral thermal tolerance: tuning gene expression to resist thermal stress.the acclimatization capacity of corals is a critical consideration in the persistence of coral reefs under stresses imposed by global climate change. the stress history of corals plays a role in subsequent response to heat stress, but the transcriptomic changes associated with these plastic changes have not been previously explored. in order to identify host transcriptomic changes associated with acquired thermal tolerance in the scleractinian coral acropora millepora, corals preconditioned to a ...201223226355
the roles and interactions of symbiont, host and environment in defining coral fitness.reef-building corals live in symbiosis with a diverse range of dinoflagellate algae (genus symbiodinium) that differentially influence the fitness of the coral holobiont. the comparative role of symbiont type in holobiont fitness in relation to host genotype or the environment, however, is largely unknown. we addressed this knowledge gap by manipulating host-symbiont combinations and comparing growth, survival and thermal tolerance among the resultant holobionts in different environments.200919629182
interactions among chronic and acute impacts on coral recruits: the importance of size-escape thresholds.newly settled recruits typically suffer high mortality from disturbances, but rapid growth reduces their mortality once size-escape thresholds are attained. ocean acidification (oa) reduces the growth of recruiting benthic invertebrates, yet no direct effects on survivorship have been demonstrated. we tested whether the reduced growth of coral recruits caused by oa would increase their mortality by prolonging their vulnerability to an acute disturbance: fish herbivory on surrounding algal turf. ...201223185875
the skeleton of the staghorn coral acropora millepora: molecular and structural characterization.the scleractinian coral acropora millepora is one of the most studied species from the great barrier reef. this species has been used to understand evolutionary, immune and developmental processes in cnidarians. it has also been subject of several ecological studies in order to elucidate reef responses to environmental changes such as temperature rise and ocean acidification (oa). in these contexts, several nucleic acid resources were made available. when combined to a recent proteomic analysis ...201424893046
a lipidomic approach to understanding free fatty acid lipogenesis derived from dissolved inorganic carbon within cnidarian-dinoflagellate symbiosis.the cnidarian-dinoflagellate symbiosis is arguably one of the most important within the marine environment in that it is integral to the formation of coral reefs. however, the regulatory processes that perpetuate this symbiosis remain unresolved. it is essential to understand these processes, if we are to elucidate the mechanisms that support growth and resource accumulation by coral host, and conversely, recently observed reduction and/or mortality of corals in response to rapid environmental c ...201223115631
chronic exposure of corals to fine sediments: lethal and sub-lethal impacts.understanding the sedimentation and turbidity thresholds for corals is critical in assessing the potential impacts of dredging projects in tropical marine systems. in this study, we exposed two species of coral sampled from offshore locations to six levels of total suspended solids (tss) for 16 weeks in the laboratory, including a 4 week recovery period. dose-response relationships were developed to quantify the lethal and sub-lethal thresholds of sedimentation and turbidity for the corals. the ...201222662225
first frozen repository for the great barrier reef coral build new tools for the continued protection and propagation of coral from the great barrier reef (gbr), an international group of coral and cryopreservation scientists known as the reef recovery initiative joined forces during the november 2011 mass-spawning event. the outcome was the creation of the first frozen bank for australian coral from two important gbr reef-building species, acropora tenuis and acropora millepora. approximately 190 frozen samples each with billions of cells were pla ...201222659104
major cellular and physiological impacts of ocean acidification on a reef building atmospheric levels of co(2) increase, reef-building corals are under greater stress from both increased sea surface temperatures and declining sea water ph. to date, most studies have focused on either coral bleaching due to warming oceans or declining calcification due to decreasing oceanic carbonate ion concentrations. here, through the use of physiology measurements and cdna microarrays, we show that changes in ph and ocean chemistry consistent with two scenarios put forward by the intergo ...201222509341
a "neural" enzyme in nonbilaterian animals and algae: preneural origins for peptidylglycine α-amidating monooxygenase.secreted peptides, produced by enzymatic processing of larger precursor molecules, are found throughout the animal kingdom and play important regulatory roles as neurotransmitters and hormones. many require a carboxy-terminal modification, involving the conversion of a glycine residue into an α-amide, for their biological activity. two sequential enzymatic activities catalyze this conversion: a monooxygenase (peptidylglycine α-hydroxylating monooxygenase or phm) and an amidating lyase (peptidyl- ...201222496439
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