Yalpani N, Srivastava L M
Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6.
Plant Physiol. 1985 Dec;79(4):963-7. doi: 10.1104/pp.79.4.963.
The gibberellin (GA) binding properties of a cytosol fraction from hypocotyls of cucumber (Cucumis sativus L. cv National Pickling) were examined using a DEAE filter paper assay, [(3)H]GA(4), and over 20 GAs, GA derivatives and other growth regulators. The results demonstrate structural specificity of the binding protein for gamma-lactonic C-19 GAs with a 3 beta-hydroxyl and a C-6 carboxyl group. Additional hydroxylations of the A, C, or D ring of the ent-gibberellane skeleton and methylation of the C-6 carboxyl impede or abolish binding affinity. Bioassay data are generally supported by the in vitro results but significantly GA(9) and GA(36), both considered to be precursors of GA(4) in cucumber, show no affinity for the binding protein. The results are discussed in relation to the active site of the putative GA(4) receptor in cucumber.
使用DEAE滤纸分析法、[³H]GA₄以及20多种赤霉素(GA)、GA衍生物和其他生长调节剂,对黄瓜(Cucumis sativus L. cv National Pickling)下胚轴胞质溶胶组分的GA结合特性进行了研究。结果表明,结合蛋白对具有3β-羟基和C-6羧基的γ-内酯C-19 GA具有结构特异性。赤霉素烷骨架的A、C或D环的额外羟基化以及C-6羧基的甲基化会阻碍或消除结合亲和力。生物测定数据通常得到体外实验结果的支持,但在黄瓜中被认为是GA₄前体的GA₉和GA₃₆对结合蛋白没有亲和力。结合黄瓜中假定的GA₄受体的活性位点对结果进行了讨论。