English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Nematode chemosensory GPCRs in  Caenorhabditis elegans  (NemChRs) are classified into 19 gene families, and are initially thought to have split from the ancestral  Rhodopsin  family of GPCRs. However, earlier studies have shown that among all 19 NemChR gene families, only the srw family has a clear sequence relationship to the ancestral  Rhodopsin  GPCR family. Yet, the phylogenetic relationships between the srw family of NemChRs and the  Rhodopsin  subfamilies are not fully understood. Also, a widespread search was not previously performed to check for the presence of putative srw family-like sequences or the other 18 NemChR families in several new protostome species outside the nematode lineage. In this study, we have investigated for the presence of 19 NemChR families across 26 eukaryotic species, covering basal eukaryotic branches and provide the first evidence that the srw family of NemChRs is indeed present across several phyla of protostomes. We could identify 29 putative orthologs of the srw family in insects (15 genes), molluscs (11 genes) and  Schistosoma mansoni  (3 genes). Furthermore, using HMM-HMM profile based comparisons and phylogenetic analysis we show that among all  Rhodopsin  subfamilies, the peptide and SOG (somatostatin/opioid/galanin) subfamilies are phylogenetically the closest relatives to the srw family of NemChRs. Taken together, we demonstrate that the srw family split from the large  Rhodopsin  family, possibly from the peptide and/or SOG subfamilies, well before the split of the nematode lineage, somewhere close to the divergence of the common ancestor of protostomes. Our analysis also suggests that the srsx family of NemChRs shares a clear sequence homology with the  Rhodopsin  subfamilies, as well as with few of the vertebrate olfactory receptors. Overall, this study provides further insights into the evolutionary events that shaped the GPCR chemosensory system in protostome species.

Insights into the Origin of Nematode Chemosensory GPCRs: Putative Orthologs of the Srw Family Are Found across Several Phyla of Protostomes