title: Comparative Evolution of Duplicated Ddx3 Genes in Teleosts: Insights from Japanese Flounder, Paralichthys olivaceus.
abstract: Following the two rounds of whole-genome duplication that occurred during deuterostome evolution, a third genome duplication event occurred in the stem lineage of ray-finned fishes. This teleost-specific genome duplication is thought to be responsible for the biological diversification of ray-finned fishes. DEAD-box polypeptide 3 (DDX3) belongs to the DEAD-box RNA helicase family. Although their functions in humans have been well studied, limited information is available regarding their function in teleosts. In this study, two teleost Ddx3 genes were first identified in the transcriptome of Japanese flounder (Paralichthys olivaceus). We confirmed that the two genes originated from teleost-specific genome duplication through synteny and phylogenetic analysis. Additionally, comparative analysis of genome structure, molecular evolution rate, and expression pattern of the two genes in Japanese flounder revealed evidence of subfunctionalization of the duplicated Ddx3 genes in teleosts. Thus, the results of this study reveal novel insights into the evolution of the teleost Ddx3 genes and constitute important groundwork for further research on this gene family.
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Zhongkai
authors.identifier: http://orcid.org/0000-0001-8909-7790
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Huayu
authors.initials: H
authors.lastname: Song
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Jinxiang
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Du
authors.affiliation: Key Laboratory of Marine Genetics and Breeding (MGB), Ministry of Education, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China qzhang@ouc.edu.cn.
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D053487:DEAD-box RNA Helicases / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D030541:Databases, Genetic; D019143:Evolution, Molecular; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D005432:Flounder / Q000235:genetics*; D020440:Gene Duplication; D016678:Genome; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D029941:Fish Proteins; D053487:DEAD-box RNA Helicases
keywords: DDX3; evolution; genome duplication; subfunctionalization; teleost