Cloning and sequence analysis of cDNAs for neurohypophysial hormones vasotocin and mesotocin for the hypothalamus of toad, Bufo japonicus.
AUTOR(ES)
Nojiri, H
RESUMO
The primary structures of the precursors of neurohypophysial hormones vasotocin (VT) and mesotocin (MT) in the hypothalamus of the toad Bufo japonicus were determined by analyzing the nucleotide sequences of the cloned cDNAs encoding them. The MT precursor consists of 125 amino acid residues containing a signal peptide followed directly by MT, which in turn is connected to the MT neurophysin by Gly-Lys-Arg, a processing and carboxyl-terminal amidation signal. In contrast, the VT precursor includes a glycoprotein of 36 amino acids following the VT neurophysin. Except for glycoprotein, the structures of MT and VT precursors are quite similar. RNA transfer blotting analysis showed that both MT and VT mRNAs are present in the brain but not in the liver, ovaries, and testes of the toad. The sequences and the structural organizations of the MT and VT precursors are highly homologous to those of their mammalian counterparts, oxytocin and arginine vasopressin precursors, respectively. This fact suggests that, in the evolutionary pathway of neurohypophysial hormones, VT is the ancestor molecule of vasopressin, while MT is that of oxytocin.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=304798Documentos Relacionados
- Vasotocin and isotocin precursors from the white sucker, Catostomus commersoni: cloning and sequence analysis of the cDNAs.
- Molecular cloning and sequence analysis of chum salmon gonadotropin cDNAs.
- Isolation and sequence analysis of cDNAs for the major potato tuber protein, patatin.
- Sequence analysis of zein cDNAs obtained by an efficient mRNA cloning method.
- Sequence analysis and comparison of cDNAs of the zein multigene family .