Ribosomal Protein Genes S23 and L35 from Amphioxus Branchiostoma belcheri tsingtauense:Identification and Copy Number  

作　　者：Xian LI Shi-Cui ZHANG Zhen-Hui LIU Hong-Yan LI 

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

出　　处：《Acta Biochimica et Biophysica Sinica》2005年第8期573-579,共7页生物化学与生物物理学报（英文版）

基　　金：This work was supported by a grant from the National Natural ScienceFoundation of China(No.30470203)

摘　　要：The complete cDNA and deduced amino acid sequences of the ribosomal proteins S23 （AmphiS23） and L35 （AmphiL35） from amphioxus Branchiostoma belcheri tsingtauense were identified in this study. AmphiS23 cDNA is 546 bp long and encodes a protein of 143 amino acids. It has a predicted molecular mass of 15,851 Da and a pI of 10.7. AmphiL35 cDNA comprises 473 bp, and codes for a protein of 123 amino acids with a predicted molecular mass of 14,543 Da and a pI of 10.8. AmphiS23 shares more than 83% identity with its homologues in the vertebrates and more than 84% identity with those in the invertebrates. AmphiL35 is more than 63% identical to its counterparts in the vertebrates and more than 52% identical to those in the invertebrates. Southern blot analysis demonstrated the existence of 1-2 copies of the S23 gene and 2-3 copies of the L35 gene in the genome of amphioxus B. belcheri tsingtauense. This is in sharp contrast to the presence of 6-13 copies of the S23 gene and 15-17 copies of the L35 gene in therat genome. It is clear that the housekeeping genes like S23 and L35 underwent a large-scale duplication in the vertebrate lineage, reinforcing the gene/genome duplication hypothesis.The complete cDNA and deduced amino acid sequences of the ribosomal proteins S23 （AmphiS23） and L35 （AmphiL35） from amphioxus Branchiostoma belcheri tsingtauense were identified in this study. AmphiS23 cDNA is 546 bp long and encodes a protein of 143 amino acids. It has a predicted molecular mass of 15,851 Da and a pI of 10.7. AmphiL35 cDNA comprises 473 bp, and codes for a protein of 123 amino acids with a predicted molecular mass of 14,543 Da and a pI of 10.8. AmphiS23 shares more than 83% identity with its homologues in the vertebrates and more than 84% identity with those in the invertebrates. AmphiL35 is more than 63% identical to its counterparts in the vertebrates and more than 52% identical to those in the invertebrates. Southern blot analysis demonstrated the existence of 1-2 copies of the S23 gene and 2-3 copies of the L35 gene in the genome of amphioxus B. belcheri tsingtauense. This is in sharp contrast to the presence of 6-13 copies of the S23 gene and 15-17 copies of the L35 gene in therat genome. It is clear that the housekeeping genes like S23 and L35 underwent a large-scale duplication in the vertebrate lineage, reinforcing the gene/genome duplication hypothesis.

关 键 词：AMPHIOXUS ribosomal protein S23 L35 copy number 

分 类 号：Q959.4[生物学—动物学] Q591.2