title: A birch gene family encoding pollen allergens and pathogenesis-related proteins.
abstract: Bet v I, the major pollen allergen of birch (Betula verrucosa), shows high sequence homology to a family of pathogenesis-related (PR) proteins that have recently been identified in several other plant species. We have used a pollen Bet v I cDNA clone and anti-Bet v I antibodies as probes to study the expression of Bet v I genes in birch cell suspension cultures under different experimental conditions. Induction of Bet v I-related proteins was detected in immunoblots of cell extracts upon co-cultivation with microbial pathogens. Northern analysis revealed the rapid induction of Bet v I transcripts in the presence of bacteria and fungi, but not by stress treatments (heat shock, metal ions) or by chemical elicitors. RNase protection experiments showed that the pathogen-inducible RNAs did not correspond to the pollen cDNA clone but most likely to the products of transcription of other members of the Bet v I gene family, sharing high sequence homology with the pollen-specific gene within the 5'-half of the coding region. We conclude that the Bet v I gene family of pollen allergens includes a subset of defense-related genes that are transcriptionally activated in the presence of microbial pathogens.
authors.affiliation: Institute of Microbiology and Genetics, University of Vienna, Vienna Biocenter, Austria.
authors.forename: I
authors.initials: I
authors.lastname: Swoboda
authors.forename: O
authors.initials: O
authors.lastname: Scheiner
authors.forename: D
authors.initials: D
authors.lastname: Kraft
authors.forename: M
authors.initials: M
authors.lastname: Breitenbach
authors.forename: E
authors.initials: E
authors.lastname: Heberle-Bors
authors.forename: O
authors.initials: O
authors.lastname: Vicente
mesh_terms: D000485:Allergens / Q000235:genetics*; D052179:Antigens, Plant; D015870:Gene Expression; D017343:Genes, Plant; D005810:Multigene Family; D010940:Plant Proteins / Q000235:genetics*; D011058:Pollen; D012333:RNA, Messenger / Q000235:genetics; D014197:Trees / Q000235:genetics*
chemical_list: D000485:Allergens; D052179:Antigens, Plant; D010940:Plant Proteins; D012333:RNA, Messenger; C061312:Bet v 1 allergen, Betula