Independent evolutionary origin of fem paralogous genes and complementary sex determination in hymenopteran insects.

Bibliographic Details
Title: Independent evolutionary origin of fem paralogous genes and complementary sex determination in hymenopteran insects.
Authors: Vasco Koch, Inga Nissen, Björn D Schmitt, Martin Beye
Source: PLoS ONE, Vol 9, Iss 4, p e91883 (2014)
Publisher Information: Public Library of Science (PLoS), 2014.
Publication Year: 2014
Collection: LCC:Medicine
LCC:Science
Subject Terms: Medicine, Science
More Details: The primary signal of sex determination in the honeybee, the complementary sex determiner (csd) gene, evolved from a gene duplication event from an ancestral copy of the fem gene. Recently, other paralogs of the fem gene have been identified in several ant and bumblebee genomes. This discovery and the close phylogenetic relationship of the paralogous gene sequences led to the hypothesis of a single ancestry of the csd genetic system of complementary sex determination in the Hymenopteran insects, in which the fem and csd gene copies evolved as a unit in concert with the mutual transfers of sequences (concerted evolution). Here, we show that the paralogous gene copies evolved repeatedly through independent gene duplication events in the honeybee, bumblebee, and ant lineage. We detected no sequence tracts that would indicate a DNA transfer between the fem and the fem1/csd genes between different ant and bee species. Instead, we found tracts of duplication events in other genomic locations, suggesting that gene duplication was a frequent event in the evolution of these genes. These and other evidences suggest that the fem1/csd gene originated repeatedly through gene duplications in the bumblebee, honeybee, and ant lineages in the last 100 million years. Signatures of concerted evolution were not detectable, implicating that the gene tree based on neutral synonymous sites represents the phylogenetic relationships and origins of the fem and fem1/csd genes. Our results further imply that the fem1 and csd gene in bumblebees, honeybees, and ants are not orthologs, because they originated independently from the fem gene. Hence, the widely shared and conserved complementary sex determination mechanism in Hymenopteran insects is controlled by different genes and molecular processes. These findings highlight the limits of comparative genomics and emphasize the requirement to study gene functions in different species and major hymenopteran lineages.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1932-6203
Relation: http://europepmc.org/articles/PMC3990544?pdf=render; https://doaj.org/toc/1932-6203
DOI: 10.1371/journal.pone.0091883
Access URL: https://doaj.org/article/9e436090d8e247cd8a5e656942484cc0
Accession Number: edsdoj.9e436090d8e247cd8a5e656942484cc0
Database: Directory of Open Access Journals
More Details
ISSN:19326203
DOI:10.1371/journal.pone.0091883
Published in:PLoS ONE
Language:English