AUTHOR=Wang Su , Yang Qingyun , Wang Ziyue , Feng Shuoqi , Li Hongyan , Ji Dongrui , Zhang Shicui 

TITLE=Evolutionary and Expression Analyses Show Co-option of khdrbs Genes for Origin of Vertebrate Brain

JOURNAL=Frontiers in Genetics

VOLUME=8

YEAR=2018

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2017.00225

DOI=10.3389/fgene.2017.00225

ISSN=1664-8021

ABSTRACT=<p>Genes generated by whole genome duplications (WGD) can be co-opted by changing their regulation process or altering their coding proteins, which has been shown contributable to the emergence of vertebrate morphological novelties such as vertebrate cartilage. Mouse <italic>khdrbs</italic> genes, differing from its invertebrate orthologs, were mainly expressed in brain, hinting that <italic>khdrbs</italic> gene family as a member of genetic toolkit may be linked to vertebrate brain development. However, the evolutionary relationship between <italic>khdrbs</italic> gene family and vertebrate brain development is unclear. First, we analyzed the evolutionary history of <italic>khdrbs</italic> gene family in metazoans, and then investigated their expression patterns during early development and in adulthood of zebrafish. We found that the duplication of <italic>khdrbs</italic> gene family by WGD took place in zebrafish, and all zebrafish <italic>khdrbs</italic> genes were predominantly expressed in the substructures of brain during early development. Given the expression of invertebrate <italic>khdrbs</italic> gene in germ line, the distinct expression domains of zebrafish <italic>khdrbs</italic> genes in brain suggested that the duplicated <italic>khdrbs</italic> genes are co-opted for promoting the evolutionary origin of vertebrate brain.</p>