Kulaeva O N, Karavaiko N N, Shipilova S V
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow.
FEBS Lett. 1995 Jun 5;366(1):26-8. doi: 10.1016/0014-5793(95)00480-w.
Zeatin-binding protein (67 +/- 2 kDa) was isolated from the cytosol of the first leaf of 10-day-old barley plants. The protein fits to all requirements for a zeatin receptor: (i) it binds [3H]trans-zeatin reversibly and specifically, (ii) it is recognized by anti-idiotype antibodies from antiserum raised against trans-zeatin, (iii) in concert with 10(-8) M trans-zeatin it activates rRNA synthesis in vitro in a transcription elongation system containing chromatin from barley leaves associated with RNA-polymerase I. In the presence of trans-zeatin, the protein activates also RNA synthesis directed by RNA-polymerase I and RNA-polymerase II in isolated nuclei from barley leaves.
玉米素结合蛋白（67±2 kDa）是从10日龄大麦植株第一片叶子的细胞质中分离出来的。该蛋白符合玉米素受体的所有要求：（i）它可逆且特异性地结合[3H]反式玉米素，（ii）它能被针对反式玉米素产生的抗血清中的抗独特型抗体识别，（iii）与10^(-8) M反式玉米素协同作用时，它能在含有与RNA聚合酶I相关的大麦叶片染色质的转录延伸系统中体外激活rRNA合成。在反式玉米素存在的情况下，该蛋白还能激活大麦叶片分离细胞核中由RNA聚合酶I和RNA聚合酶II指导的RNA合成。
