Genet. Sel. Evol. 38 (2006) 673-687
DOI: 10.1051/gse:2006028

Sox genes in grass carp (Ctenopharyngodon idella) with their implications for genome duplication and evolution

Lei Zhong^{a, b}, Xiaomu Yu^a and Jingou Tong<sup>a

a</sup>  State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Chinese Academy of Sciences, Wuhan 430072, P. R. China
^b  The Graduate School of the Chinese Academy of Sciences, Beijing 100039, P. R. China

(Received 7 February 2006; accepted 12 June 2006; published online 28 November 2006)

Abstract - The Sox gene family is found in a broad range of animal taxa and encodes important gene regulatory proteins involved in a variety of developmental processes. We have obtained clones representing the HMG boxes of twelve Sox genes from grass carp (Ctenopharyngodon idella), one of the four major domestic carps in China. The cloned Sox genes belong to group B1, B2 and C. Our analyses show that whereas the human genome contains a single copy of Sox4, Sox11 and Sox14, each of these genes has two co-orthologs in grass carp, and the duplication of Sox4 and Sox11 occurred before the divergence of grass carp and zebrafish, which support the "fish-specific whole-genome duplication" theory. An estimation for the origin of grass carp based on the molecular clock using Sox1, Sox3 and Sox11 genes as markers indicates that grass carp (subfamily Leuciscinae) and zebrafish (subfamily Danioninae) diverged approximately 60 million years ago. The potential uses of Sox genes as markers in revealing the evolutionary history of grass carp are discussed.

Key words: grass carp (Ctenopharyngodon idella) / Sox / genome duplication / co-ortholog / molecular clock

Correspondence and reprints: jgtong@ihb.ac.cn

© INRA, EDP Sciences 2006