title: Systemically wound-responsive genes in poplar trees encode proteins similar to sweet potato sporamins and legume Kunitz trypsin inhibitors.
abstract: When the lower leaves of hybrid poplar trees are mechanically wounded, several novel mRNAs accumulate in the unwounded upper leaves (Parsons TJ, Bradshaw HD, Gordon MP: Systemic accumulation of specific mRNAs in response to wounding in poplar trees, Proc Natl Acad Sci USA, in press). A partial cDNA clone corresponding to a transcript from the wound-responsive gene designated win 3 (wound-inducible) has been cloned by differential hybridization to 32P-labelled cDNA from the leaves of wounded trees. Northern blots show a large accumulation of win 3 transcripts in the unwounded leaves of wounded trees. Southern blot analysis of poplar DNA suggests that win 3 is a member of a multigene family. The nucleotide sequences of several win 3 cDNA clones have been determined, indicating that at least three win 3 gene family members are transcribed. A genomic clone of a win 3 gene family member has been isolated and a 1.5 kb Hind III fragment containing the predicted protein-coding and 5' upstream regions has been sequenced. The putative win 3 gene product is similar to the major soluble proteins of sweet potato tubers, sporamin A and sporamin B. Both Win3 and the sporamins share significant amino acid sequence identity with Kunitz-type trypsin inhibitors from legume seeds. The Kunitz family of proteinase inhibitors thus joints three other proteinase inhibitor families which are systemically responsive to wounding.
authors.affiliation: Department of Biochemistry, University of Washington, Seattle 98195.
authors.forename: H D
authors.initials: HD
authors.lastname: Bradshaw
authors.forename: J B
authors.initials: JB
authors.lastname: Hollick
authors.forename: T J
authors.initials: TJ
authors.lastname: Parsons
authors.forename: H R
authors.initials: HR
authors.lastname: Clarke
authors.forename: M P
authors.initials: MP
authors.lastname: Gordon
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D007887:Fabaceae / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D018521:Plant Physiological Phenomena; D010940:Plant Proteins / Q000235:genetics*; D010944:Plants / Q000235:genetics*; D010946:Plants, Medicinal; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014197:Trees; D014360:Trypsin Inhibitor, Kunitz Soybean / Q000235:genetics*; D014947:Wounds and Injuries
chemical_list: D010940:Plant Proteins; D012333:RNA, Messenger; C067142:sporamin protein, Ipomoea batatas; D014360:Trypsin Inhibitor, Kunitz Soybean