Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from... more Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from these organisms have been sequenced. We have, therefore, formed a "Global Invertebrate Genomics Alliance" (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture. 3 Figure 1. Metazoan relationships. This phylogeny of Metazoa is largely based on recent phylogenomic analyses by Dunn et al. (2008) and Hejnol et al. (2009). The basal nodes of the tree are shown as a polytomy based on varying results in recent analyses
Climate change is negatively affecting the stability of natural
ecosystems, especially coral reef... more Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral’s resistance to stressors can help make informed predictions on the future of corals and coral reefs.
Proceedings of the National Academy of Sciences, 2015
We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated... more We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated K(+) channels to better understand how neuronal excitability evolved. In bilaterians, the Shaker family consists of four functionally distinct gene families (Shaker, Shab, Shal, and Shaw) that share a subunit structure consisting of a voltage-gated K(+) channel motif coupled to a cytoplasmic domain that mediates subfamily-exclusive assembly (T1). We traced the origin of this unique Shaker subunit structure to a common ancestor of ctenophores and parahoxozoans (cnidarians, bilaterians, and placozoans). Thus, the Shaker family is metazoan specific but is likely to have evolved in a basal metazoan. Phylogenetic analysis suggested that the Shaker subfamily could predate the divergence of ctenophores and parahoxozoans, but that the Shab, Shal, and Shaw subfamilies are parahoxozoan specific. In support of this, putative ctenophore Shaker subfamily channel subunits coassembled with cnidarian and mouse Shaker subunits, but not with cnidarian Shab, Shal, or Shaw subunits. The KCNQ family, which has a distinct subunit structure, also appears solely within the parahoxozoan lineage. Functional analysis indicated that the characteristic properties of Shaker, Shab, Shal, Shaw, and KCNQ currents evolved before the divergence of cnidarians and bilaterians. These results show that a major diversification of voltage-gated K(+) channels occurred in ancestral parahoxozoans and imply that many fundamental mechanisms for the regulation of action potential propagation evolved at this time. Our results further suggest that there are likely to be substantial differences in the regulation of neuronal excitability between ctenophores and parahoxozoans.
HCN channels play a unique role in bilaterian physiology as the only hyperpolarizationgated
catio... more HCN channels play a unique role in bilaterian physiology as the only hyperpolarizationgated cation channels. Their voltage-gating is regulated by cyclic nucleotides and phosphatidylinositol 4,5-bisphosphate (PIP2). Activation of HCN channels provides the depolarizing current in response to hyperpolarization that is critical for intrinsic rhythmicity in neurons and the sinoatrial node. Additionally, HCN channels regulate dendritic excitability in a wide variety of neurons. Little is known about the early functional evolution of HCN channels, but the presence of HCN sequences in basal metazoan phyla and choanoflagellates, a protozoan sister group to the metazoans, indicate that the gene family predates metazoan emergence. We functionally characterized two HCN channel orthologs from Nematostella vectensis (Cnidaria, Anthozoa) to determine which properties of HCN channels were established prior to the emergence of bilaterians. We find Nematostella HCN channels share all the major functional features of bilaterian HCNs, including reversed voltage-dependence, activation by cAMP and PIP2, and block by extracellular Cs+ . Thus bilaterian-like HCN channels were already present in the common parahoxozoan ancestor of bilaterians and cnidarians, at a time when the functional diversity of voltage-gated K+ channels was rapidly expanding. NvHCN1 and NvHCN2 are expressed broadly in planulae and in both the endoderm and ectoderm of juvenile polyps.
Climate change is negatively affecting the stability of natural ecosystems, especially coral reef... more Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral's resistance to stressors can help make informed predictions on the future of corals and coral reefs.
We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated... more We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated K + channels to better understand how neuronal excitability evolved. In bilaterians, the Shaker family consists of four functionally distinct gene families (Shaker, Shab, Shal, and Shaw) that share a subunit structure consisting of a voltage-gated K + channel motif coupled to a cytoplasmic domain that mediates subfamily-exclusive assembly (T1). We traced the origin of this unique Shaker subunit structure to a common ancestor of ctenophores and parahoxozoans (cnidarians, bilaterians, and placozoans). Thus, the Shaker family is metazoan specific but is likely to have evolved in a basal metazoan. Phylogenetic analysis suggested that the Shaker subfamily could predate the divergence of ctenophores and parahoxozoans, but that the Shab, Shal, and Shaw subfamilies are parahoxozoan specific. In support of this, putative ctenophore Shaker subfamily channel subunits coassembled with cnidarian and mouse Shaker subunits, but not with cnidarian Shab, Shal, or Shaw subunits. The KCNQ family, which has a distinct subunit structure, also appears solely within the parahoxozoan lineage. Functional analysis indicated that the characteristic properties of Shaker, Shab, Shal, Shaw, and KCNQ currents evolved before the divergence of cnidarians and bilaterians. These results show that a major diversification of voltage-gated K + channels occurred in ancestral parahoxozoans and imply that many fundamental mechanisms for the regulation of action potential propagation evolved at this time. Our results further suggest that there are likely to be substantial differences in the regulation of neuronal excitability between ctenophores and parahoxozoans.
Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from... more Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from these organisms have been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture.
Opisthobranch molluscs exhibit fascinating body plans associated with the evolution
of shell loss... more Opisthobranch molluscs exhibit fascinating body plans associated with the evolution of shell loss in multiple lineages. Sea hares in particular are interesting because Aplysia californica is a well-studied model organism that offers a large suite of genetic tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and therefore lends itself to comparative analysis with A. californica. We have established an enhanced culturing procedure for B. leachii in husbandry that enabled the study of shell formation and loss in this lineage with respect to A. californica life staging.
Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from... more Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from these organisms have been sequenced. We have, therefore, formed a "Global Invertebrate Genomics Alliance" (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture. 3 Figure 1. Metazoan relationships. This phylogeny of Metazoa is largely based on recent phylogenomic analyses by Dunn et al. (2008) and Hejnol et al. (2009). The basal nodes of the tree are shown as a polytomy based on varying results in recent analyses
Climate change is negatively affecting the stability of natural
ecosystems, especially coral reef... more Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral’s resistance to stressors can help make informed predictions on the future of corals and coral reefs.
Proceedings of the National Academy of Sciences, 2015
We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated... more We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated K(+) channels to better understand how neuronal excitability evolved. In bilaterians, the Shaker family consists of four functionally distinct gene families (Shaker, Shab, Shal, and Shaw) that share a subunit structure consisting of a voltage-gated K(+) channel motif coupled to a cytoplasmic domain that mediates subfamily-exclusive assembly (T1). We traced the origin of this unique Shaker subunit structure to a common ancestor of ctenophores and parahoxozoans (cnidarians, bilaterians, and placozoans). Thus, the Shaker family is metazoan specific but is likely to have evolved in a basal metazoan. Phylogenetic analysis suggested that the Shaker subfamily could predate the divergence of ctenophores and parahoxozoans, but that the Shab, Shal, and Shaw subfamilies are parahoxozoan specific. In support of this, putative ctenophore Shaker subfamily channel subunits coassembled with cnidarian and mouse Shaker subunits, but not with cnidarian Shab, Shal, or Shaw subunits. The KCNQ family, which has a distinct subunit structure, also appears solely within the parahoxozoan lineage. Functional analysis indicated that the characteristic properties of Shaker, Shab, Shal, Shaw, and KCNQ currents evolved before the divergence of cnidarians and bilaterians. These results show that a major diversification of voltage-gated K(+) channels occurred in ancestral parahoxozoans and imply that many fundamental mechanisms for the regulation of action potential propagation evolved at this time. Our results further suggest that there are likely to be substantial differences in the regulation of neuronal excitability between ctenophores and parahoxozoans.
HCN channels play a unique role in bilaterian physiology as the only hyperpolarizationgated
catio... more HCN channels play a unique role in bilaterian physiology as the only hyperpolarizationgated cation channels. Their voltage-gating is regulated by cyclic nucleotides and phosphatidylinositol 4,5-bisphosphate (PIP2). Activation of HCN channels provides the depolarizing current in response to hyperpolarization that is critical for intrinsic rhythmicity in neurons and the sinoatrial node. Additionally, HCN channels regulate dendritic excitability in a wide variety of neurons. Little is known about the early functional evolution of HCN channels, but the presence of HCN sequences in basal metazoan phyla and choanoflagellates, a protozoan sister group to the metazoans, indicate that the gene family predates metazoan emergence. We functionally characterized two HCN channel orthologs from Nematostella vectensis (Cnidaria, Anthozoa) to determine which properties of HCN channels were established prior to the emergence of bilaterians. We find Nematostella HCN channels share all the major functional features of bilaterian HCNs, including reversed voltage-dependence, activation by cAMP and PIP2, and block by extracellular Cs+ . Thus bilaterian-like HCN channels were already present in the common parahoxozoan ancestor of bilaterians and cnidarians, at a time when the functional diversity of voltage-gated K+ channels was rapidly expanding. NvHCN1 and NvHCN2 are expressed broadly in planulae and in both the endoderm and ectoderm of juvenile polyps.
Climate change is negatively affecting the stability of natural ecosystems, especially coral reef... more Climate change is negatively affecting the stability of natural ecosystems, especially coral reefs. The dissociation of the symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral's resistance to stressors can help make informed predictions on the future of corals and coral reefs.
We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated... more We examined the origins and functional evolution of the Shaker and KCNQ families of voltage-gated K + channels to better understand how neuronal excitability evolved. In bilaterians, the Shaker family consists of four functionally distinct gene families (Shaker, Shab, Shal, and Shaw) that share a subunit structure consisting of a voltage-gated K + channel motif coupled to a cytoplasmic domain that mediates subfamily-exclusive assembly (T1). We traced the origin of this unique Shaker subunit structure to a common ancestor of ctenophores and parahoxozoans (cnidarians, bilaterians, and placozoans). Thus, the Shaker family is metazoan specific but is likely to have evolved in a basal metazoan. Phylogenetic analysis suggested that the Shaker subfamily could predate the divergence of ctenophores and parahoxozoans, but that the Shab, Shal, and Shaw subfamilies are parahoxozoan specific. In support of this, putative ctenophore Shaker subfamily channel subunits coassembled with cnidarian and mouse Shaker subunits, but not with cnidarian Shab, Shal, or Shaw subunits. The KCNQ family, which has a distinct subunit structure, also appears solely within the parahoxozoan lineage. Functional analysis indicated that the characteristic properties of Shaker, Shab, Shal, Shaw, and KCNQ currents evolved before the divergence of cnidarians and bilaterians. These results show that a major diversification of voltage-gated K + channels occurred in ancestral parahoxozoans and imply that many fundamental mechanisms for the regulation of action potential propagation evolved at this time. Our results further suggest that there are likely to be substantial differences in the regulation of neuronal excitability between ctenophores and parahoxozoans.
Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from... more Over 95% of all metazoan (animal) species comprise the “invertebrates,” but very few genomes from these organisms have been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture.
Opisthobranch molluscs exhibit fascinating body plans associated with the evolution
of shell loss... more Opisthobranch molluscs exhibit fascinating body plans associated with the evolution of shell loss in multiple lineages. Sea hares in particular are interesting because Aplysia californica is a well-studied model organism that offers a large suite of genetic tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and therefore lends itself to comparative analysis with A. californica. We have established an enhanced culturing procedure for B. leachii in husbandry that enabled the study of shell formation and loss in this lineage with respect to A. californica life staging.
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Papers by Bishoy Kamel
ecosystems, especially coral reefs. The dissociation of the
symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral’s resistance to stressors can help make informed predictions on the future of corals and coral reefs.
cation channels. Their voltage-gating is regulated by cyclic nucleotides and phosphatidylinositol
4,5-bisphosphate (PIP2). Activation of HCN channels provides the depolarizing
current in response to hyperpolarization that is critical for intrinsic rhythmicity in neurons
and the sinoatrial node. Additionally, HCN channels regulate dendritic excitability in a wide
variety of neurons. Little is known about the early functional evolution of HCN channels, but
the presence of HCN sequences in basal metazoan phyla and choanoflagellates, a protozoan
sister group to the metazoans, indicate that the gene family predates metazoan emergence.
We functionally characterized two HCN channel orthologs from Nematostella
vectensis (Cnidaria, Anthozoa) to determine which properties of HCN channels were established
prior to the emergence of bilaterians. We find Nematostella HCN channels share all
the major functional features of bilaterian HCNs, including reversed voltage-dependence,
activation by cAMP and PIP2, and block by extracellular Cs+
. Thus bilaterian-like HCN
channels were already present in the common parahoxozoan ancestor of bilaterians and
cnidarians, at a time when the functional diversity of voltage-gated K+ channels was rapidly
expanding. NvHCN1 and NvHCN2 are expressed broadly in planulae and in both the endoderm
and ectoderm of juvenile polyps.
been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a
collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage,
sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic
spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations
across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria,
Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target
7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the
oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement;
relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight
benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data
access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched
to facilitate this collaborative venture.
of shell loss in multiple lineages. Sea hares in particular are interesting because
Aplysia californica is a well-studied model organism that offers a large suite of genetic
tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and
therefore lends itself to comparative analysis with A. californica. We have established
an enhanced culturing procedure for B. leachii in husbandry that enabled the study of
shell formation and loss in this lineage with respect to A. californica life staging.
ecosystems, especially coral reefs. The dissociation of the
symbiosis between reef-building corals and their algal symbiont, or coral bleaching, has been linked to increased sea surface temperatures. Coral bleaching has significant impacts on corals, including an increase in disease outbreaks that can permanently change the entire reef ecosystem. Yet, little is known about the impacts of coral bleaching on the coral immune system. In this study, whole transcriptome analysis of the coral holobiont and each of the associate components (i.e. coral host, algal symbiont and other associated microorganisms) was used to determine changes in gene expression in corals affected by a natural bleaching event as well as during the recovery phase. The main findings include evidence that the coral holobiont and the coral host have different responses to bleaching, and the host immune system appears suppressed even a year after a bleaching event. These results support the hypothesis that coral bleaching changes 2015 The Authors. Published by the Royal Society under the terms of the Creative Commons the expression of innate immune genes of corals, and these effects can last even after recovery of symbiont populations. Research on the role of immunity on coral’s resistance to stressors can help make informed predictions on the future of corals and coral reefs.
cation channels. Their voltage-gating is regulated by cyclic nucleotides and phosphatidylinositol
4,5-bisphosphate (PIP2). Activation of HCN channels provides the depolarizing
current in response to hyperpolarization that is critical for intrinsic rhythmicity in neurons
and the sinoatrial node. Additionally, HCN channels regulate dendritic excitability in a wide
variety of neurons. Little is known about the early functional evolution of HCN channels, but
the presence of HCN sequences in basal metazoan phyla and choanoflagellates, a protozoan
sister group to the metazoans, indicate that the gene family predates metazoan emergence.
We functionally characterized two HCN channel orthologs from Nematostella
vectensis (Cnidaria, Anthozoa) to determine which properties of HCN channels were established
prior to the emergence of bilaterians. We find Nematostella HCN channels share all
the major functional features of bilaterian HCNs, including reversed voltage-dependence,
activation by cAMP and PIP2, and block by extracellular Cs+
. Thus bilaterian-like HCN
channels were already present in the common parahoxozoan ancestor of bilaterians and
cnidarians, at a time when the functional diversity of voltage-gated K+ channels was rapidly
expanding. NvHCN1 and NvHCN2 are expressed broadly in planulae and in both the endoderm
and ectoderm of juvenile polyps.
been sequenced. We have, therefore, formed a “Global Invertebrate Genomics Alliance” (GIGA). Our intent is to build a
collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage,
sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic
spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations
across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria,
Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target
7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the
oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement;
relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight
benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data
access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched
to facilitate this collaborative venture.
of shell loss in multiple lineages. Sea hares in particular are interesting because
Aplysia californica is a well-studied model organism that offers a large suite of genetic
tools. Bursatella leachii is a related tropical sea hare that lacks a shell as an adult and
therefore lends itself to comparative analysis with A. californica. We have established
an enhanced culturing procedure for B. leachii in husbandry that enabled the study of
shell formation and loss in this lineage with respect to A. californica life staging.