title: A pollen allergen-encoding gene is expressed in wheat ovaries.
abstract: To isolate genes specifically expressed at the initiation of plant embryo development we have applied a sensitive subtractive hybridization technique for three isogenic wheat lines of the so-called 'Salmon system' with either zygotic or autonomous embryo development. Here we present a gene sequence showing a high homology to grass pollen allergens of type II/III thought to be expressed in pollen tissue only. Surprisingly, the pollen allergen-like sequence, designated Tri a III, is also expressed in gynoecia of the sexual, male fertile wheat line '(aestivum)-Salmon', whereas the two parthenogenetic and male sterile wheat lines '(caudata)-Salmon' and '(kotschyi)-Salmon' completely lack any Tri a III transcript. Our data suggest a positive correlation between the expression of this clone and the manifestation of male fertility. Northern and in situ hybridization analysis revealed that, in addition to its presence in pollen, Tri a III is expressed in the parenchymatous tissue of '(aestivum)-Salmon' ovaries exclusively at the day of anthesis. This precise temporal and spatial expression pattern suggests a more general function of the pollen allergen-like sequence Tri a III not limited to the exhibition of allergens in pollen grains.
authors.affiliation: Institut für Pflanzengenetik und Kulturpflanzenforschung, Abteilung Molekulare Genetik, Gatersleben, Germany.
authors.forename: H J
authors.initials: HJ
authors.lastname: Balzer
authors.forename: L
authors.initials: L
authors.lastname: Borisiuk
authors.forename: H M
authors.initials: HM
authors.lastname: Meyer
authors.forename: F
authors.initials: F
authors.lastname: Matzk
authors.forename: H
authors.initials: H
authors.lastname: Bäumlein
mesh_terms: D000485:Allergens / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular / Q000379:methods; D018076:DNA, Complementary / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D015723:Gene Library; D008969:Molecular Sequence Data; D010312:Parthenogenesis; D011058:Pollen / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D018749:RNA, Plant / Q000032:analysis; D012098:Reproduction; D012639:Seeds / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D014908:Triticum / Q000235:genetics*
chemical_list: D000485:Allergens; D018076:DNA, Complementary; D012333:RNA, Messenger; D018749:RNA, Plant