Characterization,Evolution and Expression of the Calmodulinl Genes from the Amphioxus Branchiostoma belcheri tsingtauense  

作　　者：Jing LUAN Zhenhui LIU Shicui ZHANG Hongyan LI Chunxin FAN Lei LI 

机构地区：[1]Department of Marine Biology, Ocean University of China, Qingdao 266003, China

出　　处：《Acta Biochimica et Biophysica Sinica》2007年第4期255-264,共10页生物化学与生物物理学报（英文版）

基　　金：This work was supported by the Ministry of Science and Technology(MOST)of China ;the National Natural Science Foundation of China(No.30470203 and No.30500256)

摘　　要：Two full-length cDNAs, named CaMla and CaMlb, encoding the highly conserved calmodulinl （CAM1） proteins, were isolated from the cDNA library of amphioxus Branchiostoma belcheri tsingtauense. There are only two nucleotide differences between them, producing one amino acid difference between CaMla and CaMlb. Comparison of the amino acid sequence of CaM1 reveals that the B. belched tsingtauense CaMla is identical with CaM1 proteins of B. floridae and B. lanceolatum, Drosophila melanogaster CaM, ascidian Halocynthia roretzi CaMA and mollusk Aplysia californica CaM, and CaMlb differs only at one position （138, Asn to Asp）. The phylogenetic analysis indicates that the CaM1 in all th;ee amphioxus species appears to encode the conventional CaM and CaM2 might be derived from gene duplication of CaMI. Southern blot suggests that there are two copies of CaM1 in the genome of B. belcheri tsingtauense. Northern blot and in situ hybridization analysis shows the presence of two CaM1 mRNA transcripts with various expression levels in different adult tissues and embryonic stages in amphioxus B. belcheri tsingtauense. The evolution and diversity of metazoan CaM mRNA transcripts are also discussed.Two full-length cDNAs, named CaMla and CaMlb, encoding the highly conserved calmodulinl （CAM1） proteins, were isolated from the cDNA library of amphioxus Branchiostoma belcheri tsingtauense. There are only two nucleotide differences between them, producing one amino acid difference between CaMla and CaMlb. Comparison of the amino acid sequence of CaM1 reveals that the B. belched tsingtauense CaMla is identical with CaM1 proteins of B. floridae and B. lanceolatum, Drosophila melanogaster CaM, ascidian Halocynthia roretzi CaMA and mollusk Aplysia californica CaM, and CaMlb differs only at one position （138, Asn to Asp）. The phylogenetic analysis indicates that the CaM1 in all th;ee amphioxus species appears to encode the conventional CaM and CaM2 might be derived from gene duplication of CaMI. Southern blot suggests that there are two copies of CaM1 in the genome of B. belcheri tsingtauense. Northern blot and in situ hybridization analysis shows the presence of two CaM1 mRNA transcripts with various expression levels in different adult tissues and embryonic stages in amphioxus B. belcheri tsingtauense. The evolution and diversity of metazoan CaM mRNA transcripts are also discussed.

关 键 词：AMPHIOXUS BRANCHIOSTOMA calmodulinl EVOLUTION EXPRESSION 

分 类 号：Q513[生物学—生物化学] Q781