Phylogenetic Affinity of Rat and Some Mammalian Species Metallothionein Genes

Abstract

Metallothioneins ( are low molecular weight proteins, which have ability to bind bothmono and divalent metals and to form metal protein complexes. In mammals, MT are presentedby four isoforms (MT 1, MT 2, MT 3 and MT 4), which are encoded by the family of metallotioneingenes. The purpose of the present study was to determine the p hylogenetic affinity of different ratRattus norvegicus MT genes with other mammalian spe cies, as well as to determine the degree ofsimilarity between genes of MT isoforms within s pecies Rattus norvegicus. Therefore nucleotidesequences of MT genes were aligned, the percentage of identity and the number of gaps wascounted and a phylogenetic analysis was carrie d out. For genes of all Rattus norvegicus MTisoforms, significant similarity with other ma mmalian species Mus musculus Homo s ap iens Susscrofa was shown. The coding sequences ( of genes of Rattus norvegicus MT 1, MT 2A, MT 3and MT 4 isoforms have a significant similarity among themselves. The MT genes are hig hlyconservative, both at the interspecific and intraspecific levels, which is probably associated withtheir biological functions.