title: Cloning of an unusual natriuretic peptide from the South American coral snake Micrurus corallinus.
abstract: In the course of cloning abundant cDNAs from the South American coral snake Micrurus corallinus venom gland, we characterized a cDNA coding for a putative natriuretic peptide. All the natural natriuretic peptides described so far, possess a ring structure composed of 17 amino acids formed through an S-S bridge which is extended at the N-terminus by few to several amino acids and may be extended at the C-terminus, usually 4-7 amino acids. In contrast, the M. corallinus natriuretic peptide presents several distinct features: (a) the proform of the deduced natriuretic peptide displays an unusual C-terminus extension. This implies that the mature peptide has a long C-terminal tail or it is further extensively processed to result in the mature natriuretic peptide with the expected 4-7 amino-acid extension. (b) the deduced natriuretic peptide presents an unusual internal Cys within the ring structure. This raises the possibility of natriuretic peptides with a smaller ring structure. (c) the putative natriuretic peptide is flanked by two homologous peptides of unknown function. In addition, an analogous peptide was synthesized and assayed on perfused rat kidney, showing a dose-dependent response in urinary volume and sodium excretion. Moreover, northern-blot studies showed that M. corallinus natriuretic peptide transcripts were highly expressed in venom glands, but they were not detectable in other tissues like heart and brain, suggesting a main role for this M. corallinus natriuretic peptide in the venom gland or in the envenomation by this coral snake's bite.
authors.affiliation: Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil.
authors.forename: P L
authors.initials: PL
authors.lastname: Ho
authors.forename: M B
authors.initials: MB
authors.lastname: Soares
authors.forename: T
authors.initials: T
authors.lastname: Maack
authors.forename: I
authors.initials: I
authors.lastname: Gimenez
authors.forename: G
authors.initials: G
authors.lastname: Puorto
authors.forename: M F
authors.initials: MF
authors.lastname: Furtado
authors.forename: I
authors.initials: I
authors.lastname: Raw
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000737:chemistry; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004546:Elapid Venoms / Q000737:chemistry*; D017815:Elapidae; D007668:Kidney / Q000187:drug effects; D008297:Male; D008969:Molecular Sequence Data; D009318:Natriuresis; D020097:Natriuretic Peptide, Brain; D020098:Natriuretic Peptide, C-Type; D009419:Nerve Tissue Proteins / Q000737:chemistry; D010446:Peptide Fragments / Q000494:pharmacology; D010455:Peptides / Q000737:chemistry / Q000235:genetics* / Q000494:pharmacology; D021382:Protein Sorting Signals / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013020:South America
chemical_list: D004546:Elapid Venoms; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D010455:Peptides; D021382:Protein Sorting Signals; D011506:Proteins; D012333:RNA, Messenger; C053972:micrurus venom; C110030:natriuretic peptide, Micrurus; D020097:Natriuretic Peptide, Brain; D020098:Natriuretic Peptide, C-Type; D009320:Atrial Natriuretic Factor