水稻半胱氨酸蛋白酶抑制剂基因的克隆及其mRNA在水稻中的组成型表达

从40年代发现豆科植物中存在蛋白酶蛋白抑制剂以来,在动物、植物和微生物体内已发现普遍存在着多种类型的蛋白酶抑制剂(PI)。人们往往是为了研究某种蛋白酶的作用机制或出于某种应用目的去分离和研究PI的,对PI的真正生理功能尚不十分清楚。一般认为除防止体内不必要的蛋白降解作用、调节蛋白代谢及调节各种蛋白酶的生理活性外,很多植物的PI还具有抑制某些病源微生物及某些昆虫体内蛋白酶的作用,从而对植物有防卫功能。Hilder等和Johnson等已分别将属于丝氨酸蛋白酶抑制剂的豇豆蛋白酶抑制剂及马铃薯PⅠⅠ和PⅠⅡ基因转入烟草,结果转基因烟草对烟芽夜蛾(He-

Cloning of Rice Cysteine Proteinase Inhibitor Gene and Constitutive Expression of Its mRNA in Rice Plants

To study the physiological functions of plant proteinase inhibitors and its potential application in genetic modification of plants for pathogen-or insect-resistance, a gene coding for rice cysteine proteinase inhibitor (Oryzacystatinl, OC-1) was amplified from rice cDNAs using PCR technique and cloned in E. coli. Its nucleotide sequence was determined. The preliminary results of Northern blot analysis of rice RNA, using the cloned OC-1 gene as a probe suggested a constitutive expression pattern for OC-1 in rice plants.