title: Cloning and sequencing of mRNAs coding for two adult alpha globin chains of the salamander Pleurodeles waltlii.
abstract: A cDNA library of erythrocyte mRNAs was established from immature red blood cells of the adult amphibian, Pleurodeles waltlii (urodele; salamander). The cDNA clones corresponding to the four adult globin chains were first identified and characterized by positive selection and the cDNAs derived from the two (major and minor) alpha-globin chains sequenced. The sequences presented contain both the complete 3'-noncoding region and the coding region of both chains, with the exception of the first nine codons of the minor alpha-chain, and a portion of the 5'-noncoding region of the major chain. The amino acid sequences of the encoded alpha-globin polypeptides have been deduced and compared with those of Xenopus laevis and of man. These comparative studies suggest that the alpha-globins of Pleurodeles waltlii and Xenopus laevis may have diverged from a common ancestral gene at the time when mammalian and amphibian lines diverged, and that they then evolved separately. Duplication of the alpha-gene, which is responsible for the polypeptide heterogeneity, appears to have occurred earlier in Pleurodeles waltlii than in Xenopus laevis.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D004262:DNA Restriction Enzymes; D005796:Genes; D005914:Globins / Q000235:genetics*; D046911:Macromolecular Substances; D010999:Pleurodeles / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics* / Q000302:isolation & purification; D012455:Salamandridae / Q000235:genetics*
chemical_list: D046911:Macromolecular Substances; D012333:RNA, Messenger; D005914:Globins; D004247:DNA; D004262:DNA Restriction Enzymes