Wang C S, Huang J C, Hu J H
Graduate Institute of Agricultural Biotechnology, National Chung Hsing University, Taichung, Taiwan.
Plant Mol Biol. 1999 Jul;40(5):807-14. doi: 10.1023/a:1006285028495.
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.
百合PR - 10属于细胞内病程相关（IPR）蛋白家族。基因组Southern分析表明，PR - 10由一个多基因家族编码。从麝香百合中分离出的7个编码百合PR - 10的异源cDNA克隆，根据序列比较和Southern杂交被分为两个亚类。两个亚类（以PR - 10c和d为代表）之间的总体序列相似性为82%。这两个cDNA包含一个474 bp的开放阅读框，编码157个氨基酸。5'和3'非翻译区的相似性较低，但编码区的相似性较高。百合PR - 10基因在百合植株的花药和其他各种器官中受脱落酸（ABA）和茉莉酸甲酯（MeJA）诱导。ABA和MeJA在百合花药中对PR - 10基因的诱导是通过两条独立的信号转导途径发生的。蛋白磷酸酶抑制剂冈田酸抑制MeJA诱导的PR - 10基因表达，作用于MeJA下游。此外，蛋白激酶抑制剂星形孢菌素抑制MeJA诱导的PR - 10基因表达，这意味着在花药中，星形孢菌素敏感的蛋白激酶活性存在于MeJA下游。然而，冈田酸不抑制ABA诱导的PR - 10基因表达，而星形孢菌素则抑制。这些观察结果表明，除了已知的ABA通过激活JA或MeJA诱导基因表达的途径外，花药中还存在一条MeJA非依赖的ABA诱导途径。ABA诱导的替代途径涉及ABA下游的星形孢菌素敏感的蛋白激酶活性。
