Comparative genomics and transcriptomics in ants provide new insights into the evolution and function of odorant binding and chemosensory proteins
Published Date:Aug 26 2014
Source:BMC Genomics. 15(1).
Gene Expression Regulation
Pubmed Central ID:PMC4161878
Funding:1DP2GM105454-01/DP/NCCDPHP CDC HHS/United States
DP2 GM105454/GM/NIGMS NIH HHS/United States
GM066699/GM/NIGMS NIH HHS/United States
T32 GM066699/GM/NIGMS NIH HHS/United States
The complex societies of ants and other social insects rely on sophisticated chemical communication. Two families of small soluble proteins, the odorant binding and chemosensory proteins (OBPs and CSPs), are believed to be important in insect chemosensation. To better understand the role of these proteins in ant olfaction, we examined their evolution and expression across the ants using phylogenetics and sex- and tissue-specific RNA-seq.
We find that subsets of both OBPs and CSPs are expressed in the antennae, contradicting the previous hypothesis that CSPs have replaced OBPs in ant olfaction. Both protein families have several highly conserved clades with a single ortholog in all eusocial hymenopterans, as well as clades with more dynamic evolution and many taxon-specific radiations. The dynamically evolving OBPs and CSPs have been hypothesized to function in chemical communication. Intriguingly, we find that seven members of the conserved clades are expressed specifically in the antennae of the clonal raider ant Cerapachys biroi, whereas only one dynamically evolving CSP is antenna specific. The orthologs of the conserved, antenna-specific C. biroi genes are also expressed in antennae of the ants Camponotus floridanus and Harpegnathos saltator, indicating that antenna-specific expression of these OBPs and CSPs is conserved across ants. Most members of the dynamically evolving clades in both protein families are expressed primarily in non-chemosensory tissues and thus likely do not fulfill chemosensory functions.
Our results identify candidate OBPs and CSPs that are likely involved in conserved aspects of ant olfaction, and suggest that OBPs and CSPs may not rapidly evolve to recognize species-specific signals.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-718) contains supplementary material, which is available to authorized users.
image/gif image/jpeg image/gif image/jpeg image/gif image/jpeg image/gif image/jpeg application/pdf application/pdf text/csv text/csv text/csv application/pdf text/plain text/plain
You May Also Like: