Chory J, Voytas D F, Olszewski N E, Ausubel F M
Department of Genetics, Harvard Medical School, Boston, Massachusetts 02114.
Plant Physiol. 1987 Jan;83(1):15-23. doi: 10.1104/pp.83.1.15.
Two-dimensional gel electrophoresis was used to characterize the molecular mechanism of gibberellin-induced stem elongation in maize and pea. Dwarf mutants of maize (d-5) and pea (Progress No. 9) lack endogenous gibberellin (GA(1)) but become phenotypically normal with exogenous applications of this hormone. Sections from either etiolated maize or green pea seedlings were incubated in the presence of [(35)S] methionine for 3 hours with or without gibberellin. Labeled proteins from soluble and particulate fractions were analyzed by two-dimensional gel electrophoresis and specific changes in the patterns of protein synthesis were observed upon treatment with gibberellin. Polyadenylated mRNAs from etiolated or green maize shoots and green pea epicotyls treated or not with gibberellin (a 0.5 to 16 hour time course) were assayed by translation in a rabbit reticulocyte extract and separation of products by two-dimensional gel electrophoresis. Both increases and decreases in the levels of specific polypeptides were seen for pea and corn, and these changes were observed within 30 minutes of treatment with gibberellin. Together, these data indicate that gibberellin induces changes in the expression of a subset of gene products within elongating dwarfs. This may be due to changes in transcription rate, mRNA stability, or increased efficiency of translation of certain mRNAs.
二维凝胶电泳用于表征赤霉素诱导玉米和豌豆茎伸长的分子机制。玉米（d-5）和豌豆（Progress No. 9）的矮化突变体缺乏内源性赤霉素（GA(1)），但外源施加这种激素后表型恢复正常。将黄化玉米或绿色豌豆幼苗的切片在含[(35)S]甲硫氨酸的条件下孵育3小时，添加或不添加赤霉素。用二维凝胶电泳分析可溶性和颗粒部分的标记蛋白质，并观察到用赤霉素处理后蛋白质合成模式的特定变化。对经或未经赤霉素处理（0.5至16小时时间进程）的黄化或绿色玉米芽和绿色豌豆上胚轴的聚腺苷酸化mRNA，在兔网织红细胞提取物中进行翻译测定，并通过二维凝胶电泳分离产物。豌豆和玉米中特定多肽水平均有增加和减少，且这些变化在赤霉素处理后30分钟内即可观察到。这些数据共同表明，赤霉素诱导伸长的矮化植株中一部分基因产物的表达发生变化。这可能是由于转录速率、mRNA稳定性的改变，或某些mRNA翻译效率的提高所致。
