atonal- and achaete-scute-related genes in the annelid Platynereis dumerilii: insights into the evolution of neural basic-Helix-Loop-Helix genes. Export

@article{citeulike:2880824, abstract = {BACKGROUND: Functional studies in model organisms, such as vertebrates and Drosophila, have shown that basic Helix-loop-Helix (bHLH) proteins have important roles in different steps of neurogenesis, from the acquisition of neural fate to the differentiation into specific neural cell types. However, these studies highlighted many differences in the expression and function of orthologous bHLH proteins during neural development between vertebrates and Drosophila. To understand how the functions of neural bHLH genes have evolved among bilaterians, we have performed a detailed study of bHLH genes during nervous system development in the polychaete annelid, Platynereis dumerilii, an organism which is evolutionary distant from both Drosophila and vertebrates. RESULTS: We have studied Platynereis orthologs of the most important vertebrate neural bHLH genes, i.e. achaete-scute, neurogenin, atonal, olig, and NeuroD genes, the latter two being genes absent of the Drosophila genome. We observed that all these genes have specific expression patterns during nervous system formation in Platynereis. Our data suggest that in Platynereis, like in vertebrates but unlike Drosophila, (i) neurogenin is the main proneural gene for the formation of the trunk central nervous system, (ii) achaete-scute and olig genes are involved in neural subtype specification in the central nervous system, in particular in the specification of the serotonergic phenotype. In addition, we found that the Platynereis NeuroD gene has a broad and early neuroectodermal expression, which is completely different from the neuronal expression of vertebrate NeuroD genes. CONCLUSION: Our analysis suggests that the Platynereis bHLH genes have both proneural and neuronal specification functions, in a way more akin to the vertebrate situation than to that of Drosophila. We conclude that these features are ancestral to bilaterians and have been conserved in the vertebrates and annelids lineages, but have diverged in the evolutionary lineage leading to Drosophila.}, author = {Simionato, Elena and Kerner, Pierre and Dray, Nicolas and Le Gouar, Martine and Ledent, Val\'{e}rie and Arendt, Detlev and Vervoort, Michel}, citeulike-article-id = {2880824}, citeulike-linkout-0 = {http://dx.doi.org/10.1186/1471-2148-8-170}, citeulike-linkout-1 = {http://view.ncbi.nlm.nih.gov/pubmed/18541016}, citeulike-linkout-2 = {http://www.hubmed.org/display.cgi?uids=18541016}, day = {09}, doi = {10.1186/1471-2148-8-170}, issn = {1471-2148}, journal = {BMC evolutionary biology}, keywords = {platynereis}, month = {June}, pages = {170+}, posted-at = {2008-10-06 19:05:11}, priority = {2}, title = {atonal- and achaete-scute-related genes in the annelid Platynereis dumerilii: insights into the evolution of neural basic-Helix-Loop-Helix genes.}, url = {http://dx.doi.org/10.1186/1471-2148-8-170}, volume = {8}, year = {2008} }

TY - JOUR ID - citeulike:2880824 L3 - citeulike-article-id:2880824 N2 - BACKGROUND: Functional studies in model organisms, such as vertebrates and Drosophila, have shown that basic Helix-loop-Helix (bHLH) proteins have important roles in different steps of neurogenesis, from the acquisition of neural fate to the differentiation into specific neural cell types. However, these studies highlighted many differences in the expression and function of orthologous bHLH proteins during neural development between vertebrates and Drosophila. To understand how the functions of neural bHLH genes have evolved among bilaterians, we have performed a detailed study of bHLH genes during nervous system development in the polychaete annelid, Platynereis dumerilii, an organism which is evolutionary distant from both Drosophila and vertebrates. RESULTS: We have studied Platynereis orthologs of the most important vertebrate neural bHLH genes, i.e. achaete-scute, neurogenin, atonal, olig, and NeuroD genes, the latter two being genes absent of the Drosophila genome. We observed that all these genes have specific expression patterns during nervous system formation in Platynereis. Our data suggest that in Platynereis, like in vertebrates but unlike Drosophila, (i) neurogenin is the main proneural gene for the formation of the trunk central nervous system, (ii) achaete-scute and olig genes are involved in neural subtype specification in the central nervous system, in particular in the specification of the serotonergic phenotype. In addition, we found that the Platynereis NeuroD gene has a broad and early neuroectodermal expression, which is completely different from the neuronal expression of vertebrate NeuroD genes. CONCLUSION: Our analysis suggests that the Platynereis bHLH genes have both proneural and neuronal specification functions, in a way more akin to the vertebrate situation than to that of Drosophila. We conclude that these features are ancestral to bilaterians and have been conserved in the vertebrates and annelids lineages, but have diverged in the evolutionary lineage leading to Drosophila. JF - BMC evolutionary biology SN - 1471-2148 TI - atonal- and achaete-scute-related genes in the annelid Platynereis dumerilii: insights into the evolution of neural basic-Helix-Loop-Helix genes. VL - 8 SP - 170 KW - platynereis AU - Simionato, Elena AU - Kerner, Pierre AU - Dray, Nicolas AU - Le Gouar, Martine AU - Ledent, Valérie AU - Arendt, Detlev AU - Vervoort, Michel PY - 2008/06/09/ UR - http://dx.doi.org/10.1186/1471-2148-8-170 ER -