The ATF/CREB family of transcription factors represents a large group of basic region-leucine zipper (bZip) proteins that regulate diverse cellular responses. Here we carried out a comprehensive analysis of ATF/CREB family members in 22 representative animal species. The family probably originated from the early diverging metazoan and significantly expanded in vertebrates due to multiple whole genome duplication. Duplicates of atf6 were derived from 2R, and duplicates of creb1, crem, jdp2, creb5, atf4, atf5 and atf7 were products of 3R. We also isolated 21 ATF/CREBs, belonging to 6 subfamilies from Nile tilapia. Based on transcriptome data, most members were found to be dominantly expressed in the head kidney, heart, brain and testis. Some ATF/CREBs displayed sexual dimorphic expression in gonad at 5, 90 and 180 dah (days after hatching), but not at 30 dah. creb1a and atf4a were found to be expressed mainly in phase I and II oocytes of the ovary; while creb1b and atf4b mainly in spermatogenic cells of the testis, indicating divergence of duplicated genes from 3R which suggested neofunctionalization or subfunctionalization in gonad. This is the first genome-wide screening and evolutionary analysis of ATF/CREB family in different animals, particularly in teleosts. The expression analysis of this family in tilapia gonad provided a fundamental clue for understanding their important roles in sex differentiation and gonadal development in teleosts.

转录因子的ATF / CREB家族代表一大群调节各种细胞反应的碱性区域-亮氨酸拉链（bZip）蛋白。在这里，我们对22种代表性动物的ATF / CREB家族成员进行了全面分析。该家族可能起源于早期的后生动物，并且由于多次全基因组复制而在脊椎动物中显着扩展。atf6的重复项源自2R，而creb1，crem，jdp2，creb5，atf4，atf5和atf7重复项是3R的产品。我们还分离了21个ATF / CREB，它们属于尼罗罗非鱼的6个亚科。根据转录组数据，发现大多数成员在头部肾脏，心脏，大脑和睾丸中主要表达。一些ATF / CREB在性腺中在第5、90和180 dah（孵化后几天）表现出性二态表达，但在第30 dah则没有。发现creb1a和atf4a主要在卵巢的I和II期卵母细胞中表达。而creb1b和atf4b主要在睾丸的生精细胞中，表明来自3R的重复基因存在分歧，这表明性腺中有新功能或亚功能。这是首次在不同动物，尤其是硬骨鱼中对ATF / CREB家族进行全基因组筛选和进化分析。该家族在罗非鱼性腺中的表达分析为了解其在硬骨鱼的性别分化和性腺发育中的重要作用提供了基本线索。