,Characterization, Evolution and Tissue-specific Expression of AmphiCalbin, a Novel Gene Encoding EF

• 作 者: Jing LUAN Shicui ZHANG Zhenhui LIU Chunxin FAN Guangdong JI Lei LI
• 机 构: Department of Marine Biology, Ocean University of China, Qingdao 266003, China
• 出 处: 生物化学与生物物理学报(英文版)
• 发表日期: 2007年11期
• 关键词: amphioxus Branchiostoma EF-hand calcium-binding protein evolution expression

An amphioxus full-length cDNA, AmphiCalbin, encoding a novel EF-hand calcium-binding protein (EFCaBP), was isolated from the gut cDNA library of amphioxus Branchiostoma belcheri. It consists of 1321 bp with a 636 bp open reading frame encoding a protein of 211 amino acids with a molecular mass of approximately 24.5 kDa. The phylogenetic analysis offers two interesting inferences. First, AmphiCalbin clusters with a group of unnamed EFCaBPs that are differentiated from other identified EFCaBPs. Second,AmphiCalbin falls at the base of the vertebrate unnamed EFCaBPs clade, probably representing their prototype.This is also corroborated by the fact that AmphiCalbin has an exon-intron organization identical to that of vertebrate unnamed EFCaBP genes. Both tissue-section in situ hybridization and whole-mount in situ hybridization prove a tissue-specific expression patte of AmphiCalbin, with high levels of expression in the digestive system and gonads. It is proposed that AmphiCalbin might play a role in the digestive system and gonads. These observations lay the foundation for further understanding of the function of the unnamed EFCaBPs.