title: Characterization and phylogeny of two beta-cytoskeletal actins from Hemibarbus mylodon (Cyprinidae, Cypriniformes), a threatened fish species in Korea.
abstract: Complementary DNA and genomic sequences representing two different beta-actins were isolated from a threatened freshwater fish species Hemibarbus mylodon. The beta-actin 1 and 2 encoded an identical number of amino acids (375 aa), and shared 88.8 and 99.7% of identity at coding nucleotide and amino acid levels, respectively. Genomic open reading frame (ORF) sequences of both isoforms contained five translated exons interrupted by four introns with conserved GT/AG exon/intron boundary rule. Semi-quantitative RT-PCR showed that the two isoform mRNAs were ubiquitously detected in all tissues tested, but transcript levels were variable across tissues. Phylogenetic analysis showed that H. mylodon beta-actin 1 and 2 were clustered into two distinct major and minor branches of Cypriniformes, respectively. Comparisons of the 5'-upstream region and 3'-UTR of H. mylodon beta-actin 1 also showed a high degree of homology with those of the major teleost beta-actins and warmblooded vertebrate beta-cytoskeletal actins, suggesting their more recent common origin.
authors.affiliation: Department of Aquaculture, Institute of Marine Living Modified Organisms, Pukyong National University, Busan 608-737, South Korea.
authors.forename: Keun-Yong
authors.initials: KY
authors.lastname: Kim
authors.forename: Sang Yoon
authors.initials: SY
authors.lastname: Lee
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Cho
authors.forename: In Chul
authors.initials: IC
authors.lastname: Bang
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Kim
authors.forename: Yoon Kwon
authors.initials: YK
authors.lastname: Nam
mesh_terms: D020413:3' Untranslated Regions / Q000737:chemistry; D000199:Actins / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003530:Cyprinidae / Q000235:genetics* / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000737:chemistry / Q000235:genetics*; D005260:Female; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics*; D007723:Korea; D008297:Male; D008969:Molecular Sequence Data; D009928:Organ Specificity / Q000235:genetics; D010802:Phylogeny; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics
chemical_list: D020413:3' Untranslated Regions; D000199:Actins; D003598:Cytoskeletal Proteins; D029941:Fish Proteins; D020033:Protein Isoforms