title: A dehydrin cognate protein from pea (Pisum sativum L.) with an atypical pattern of expression.
abstract: Dehydrins are a family of proteins characterised by conserved amino acid motifs, and induced in plants by dehydration or treatment with ABA. An antiserum was raised against a synthetic oligopeptide based on the most highly conserved dehydrin amino acid motif, the lysine-rich (core sequence KIKEK-LPG). This antiserum detected a novel M(r) 40,000 polypeptide and enabled isolation of a corresponding cDNA clone, pPsB61 (B61). The deduced amino acid sequence contained two lysine-rich blocks, however the remainder of the sequenced differed markedly from other pea dehydrins. Surprisingly, the sequence contained a stretch of serine residues, a characteristic common to dehydrins from many plant species but which is missing in pea dehydrin. The expression patterns of B61 mRNA and polypeptide were distinctively different from those of the pea dehydrins during seed development, germination and in young seedlings exposed to dehydration stress or treated with ABA. In particular, dehydration stress led to slightly reduced levels of B61 RNA, and ABA application to young seedlings had no marked effect on its abundance. The M(r) 40,000 polypeptide is thus related to pea dehydrin by the presence of the most highly conserved amino acid sequence motifs, but lacks the characteristic expression pattern of dehydrin. By analogy with heat shock cognate proteins we refer to this protein as a dehydrin cognate.
authors.affiliation: Division of Plant Industry, CSIRO, Canberra, Australia.
authors.forename: M
authors.initials: M
authors.lastname: Robertson
authors.forename: P M
authors.initials: PM
authors.lastname: Chandler
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D017124:Conserved Sequence; D003429:Cross Reactions; D003890:Desiccation; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000737:chemistry / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics; D012639:Seeds / Q000737:chemistry / Q000187:drug effects / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D003313:Zea mays / Q000235:genetics / Q000276:immunology
chemical_list: D010446:Peptide Fragments; D010940:Plant Proteins; D012333:RNA, Messenger; C070556:dehydrin proteins, plant; D000040:Abscisic Acid