Characterization of two subclasses of PR-10 transcripts in lily anthers and induction of their genes through separate signal transduction pathways.
The lily PR-10 belongs to a family of intracellular pathogenesis-related (IPR) proteins. Genomic Southern analysis indicates that the PR-10 is encoded by a family of multiple genes. Seven heterogeneous cDNA clones encoding lily PR-10 from Lilium longiflorum are divided into two subclasses based on sequence comparison and Southern hybridization. A 82% overall sequence similarity was found between the two subclasses (represented by PR-10c and d). The two cDNAs include an open reading frame of 474 bp encoding 157 amino acids. 5'- and 3'-untranslated regions exhibit low similarity, but similarity is high in the coding region. The lily PR-10 genes are induced by abscisic acid (ABA) and methyl jasmonate (MeJA) in the anther and various other organs of lily plants. The induction of PR-10 genes by ABA and MeJA in lily anthers occurs by two separate signal transduction pathways. The protein phosphatase inhibitor okadaic acid inhibits the MeJA-induced expression of PR-10 genes downstream of MeJA. In addition, the protein kinase inhibitor staurosporine inhibits the MeJA-induced expression of PR-10 genes, implying that an activity of staurosporine-sensitive protein kinases exists downstream of MeJA in the anther. However, okadaic acid does not inhibit the ABA-induced expression of PR-10 genes whereas staurosporine does. These observations suggest that, in addition to the known pathway that ABA induces gene expression by activating JA or MeJA, a MeJA-independent pathway of ABA induction exists in the anther. The alternative pathway of ABA induction involves a staurosporine-sensitive protein kinase activity downstream of ABA.
Wang
C S
CS
Graduate Institute of Agricultural Biotechnology, National Chung Hsing University, Taichung, Taiwan.
Huang
J C
JC
Hu
J H
JH
D000040:Abscisic Acid / Q000494:pharmacology; D000085:Acetates / Q000494:pharmacology; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology; D018076:DNA, Complementary; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006026:Glycoside Hydrolases / Q000235:genetics; D019668:Liliaceae / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D005810:Multigene Family; D019319:Okadaic Acid / Q000494:pharmacology; D054883:Oxylipins; D010940:Plant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D015398:Signal Transduction; D014158:Transcription, Genetic
D000085:Acetates; D003517:Cyclopentanes; D018076:DNA, Complementary; D054883:Oxylipins; D010940:Plant Proteins; D011994:Recombinant Proteins; C053376:pathogenesis-related proteins, plant; D019319:Okadaic Acid; D000040:Abscisic Acid; C072239:methyl jasmonate; D006026:Glycoside Hydrolases