Lawton K, Ward E, Payne G, Moyer M, Ryals J
Agricultural Biotechnology Research Unit, CIBA-GEIGY Corporation, Research Triangle Park, NC 27709.
Plant Mol Biol. 1992 Aug;19(5):735-43. doi: 10.1007/BF00027070.
Complementary DNA clones encoding acidic and basic isoforms of the class III chitinase were isolated from Nicotiana tabacum. The clones share ca. 65% identity, are equally homologous to the class III chitinases from cucumber and Arabidopsis, and are members of small gene families in tobacco. An acidic class III chitinase was purified from the intercellular fluid of tobacco leaves infected with tobacco mosaic virus (TMV). Partial amino acid sequencing of the protein confirmed that it was encoded by one of the cDNA clones. The mRNAs of the class III chitinases are coordinately expressed in response to TMV infection, both in infected and uninfected tissue. The acidic and basic class III chitinases constitute previously undescribed pathogenesis-related proteins in tobacco.
从烟草中分离出编码III类几丁质酶酸性和碱性同工型的互补DNA克隆。这些克隆约有65%的同源性，与黄瓜和拟南芥的III类几丁质酶具有同等同源性，并且是烟草中小基因家族的成员。从感染烟草花叶病毒（TMV）的烟草叶片细胞间液中纯化出一种酸性III类几丁质酶。该蛋白的部分氨基酸测序证实它由其中一个cDNA克隆编码。III类几丁质酶的mRNA在受TMV感染的组织和未受感染的组织中均对TMV感染产生协同表达。酸性和碱性III类几丁质酶构成了烟草中以前未描述过的病程相关蛋白。
