title: Molecular Evolution of Aralkylamine N-Acetyltransferase in Fish: A Genomic Survey.
abstract: All living organisms synchronize biological functions with environmental changes; melatonin plays a vital role in regulating daily and seasonal variations. Due to rhythmic activity of the timezyme aralkylamine N-acetyltransferase (AANAT), the blood level of melatonin increases at night and decreases during daytime. Whereas other vertebrates have a single form of AANAT, bony fishes possess various isoforms of aanat genes, though the reasons are still unclear. Here, we have taken advantage of multiple unpublished teleost aanat sequences to explore and expand our understanding of the molecular evolution of aanat in fish. Our results confirm that two rounds of whole-genome duplication (WGD) led to the existence of three fish isoforms of aanat, i.e., aanat1a, aanat1b, and aanat2; in addition, gene loss led to the absence of some forms from certain special fish species. Furthermore, we suggest the different roles of two aanat1s in amphibious mudskippers, and speculate that the loss of aanat1a, may be related to terrestrial vision change. Several important sites of AANAT proteins and regulatory elements of aanat genes were analyzed for structural comparison and functional forecasting, respectively, which provides insights into the molecular evolution of the differences between AANAT1 and AANAT2.
authors.affiliation: BGI Education Center, University of Chinese Academy of Sciences, Shenzhen 518083, China. lijia1@genomics.cn.|Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen 518083, China. lijia1@genomics.cn.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen 518083, China. youxinxin@genomics.cn.
authors.forename: Xinxin
authors.initials: X
authors.lastname: You
authors.affiliation: Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen 518083, China. bianchao@genomics.cn.|BGI-Zhenjiang Institute of Hydrobiology, Zhenjiang 212000, China. bianchao@genomics.cn.
authors.forename: Chao
authors.initials: C
authors.lastname: Bian
authors.affiliation: BGI Education Center, University of Chinese Academy of Sciences, Shenzhen 518083, China. yuhui@genomics.cn.|Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen 518083, China. yuhui@genomics.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Yu
authors.affiliation: Molecular Genomics Laboratory, National Institutes of Health, Bethesda, MD 20892, USA. coons@mail.nih.gov.
authors.forename: Steven L
authors.initials: SL
authors.lastname: Coon
authors.affiliation: BGI Education Center, University of Chinese Academy of Sciences, Shenzhen 518083, China. shiqiong@genomics.cn.|Shenzhen Key Lab of Marine Genomics, Guangdong Provincial Key Lab of Molecular Breeding in Marine Economic Animals, BGI, Shenzhen 518083, China. shiqiong@genomics.cn.|BGI-Zhenjiang Institute of Hydrobiology, Zhenjiang 212000, China. shiqiong@genomics.cn.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Shi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D047068:Arylalkylamine N-Acetyltransferase / Q000737:chemistry / Q000235:genetics*; D019143:Evolution, Molecular; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics*; D005399:Fishes / Q000235:genetics*; D018628:Gene Dosage; D016678:Genome; D008969:Molecular Sequence Data; D010802:Phylogeny; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment
chemical_list: D029941:Fish Proteins; D020033:Protein Isoforms; D047068:Arylalkylamine N-Acetyltransferase
keywords: Whole-Genome Duplication (WGD); aralkylamine N-acetyltransferase; gene loss; molecular evolution; phylogenetic analysis; synteny