title: Isolation of metallothionein genes and in silico structural characterization of their proteins using molecular modeling from yak (Bos grunniens).
abstract: Yak metallothioneins (BgMTs) are cysteine-rich metal-chelating proteins with highly conserved cysteine residues in their amino acid sequences. The 3D structures of the Cd(7)-BgMTs reconstructed by molecular modeling included two domains: the β-domain with M(3)(S(cys))(9) metal-thiolate clusters and the α-domain with M(4)(S(cys))(11) metal-thiolate clusters. An unusual variant was found at position 30 (Cys30→Ser30) in BgMT-III, which is usually conserved in the mammalian MT-I/-II (Cys29) and MT-III (Cys30). The variant residue of BgMT-III may play a key role in yak genetic evolution, metal-binding activity, dynamic conformation, and heavy metal metabolism. BgMT-III contained a Thr insertion at position 5 (T(5)), which may loosen the structure of the β-domain of BgMT-III, and a conserved C(6)PCP(9) motif, which may provide an interacting surface for protein-protein interactions. There is also an acidic hexapeptide insertion (E(55)GAEAE(60)) that could regulate the particular interdomain interactions and lead to the conformational change in the β-domain.
authors.affiliation: College of Animal Science and Technology, Gansu Agricultural University, No. 1 Yingmen Village, Anning District, Lanzhou 730070, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Zhang
authors.forename: Jianping
authors.initials: J
authors.lastname: Wu
authors.forename: Xinrong
authors.initials: X
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Binyin
authors.initials: B
authors.lastname: Ma
mesh_terms: D000222:Adaptation, Physiological; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle / Q000235:genetics* / Q000502:physiology; D019295:Computational Biology; D004777:Environment; D019143:Evolution, Molecular; D006801:Humans; D008668:Metallothionein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008670:Metals / Q000378:metabolism; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
chemical_list: D008670:Metals; D008668:Metallothionein