Sáez-Vásquez J, Raynal M, Delseny M
Laboratoire de Physiologie et Biologie Moléculaire des Plantes, Unité de Recherche Associée 565 du Centre National de la Recherche Scientifique, Université de Perpignan, France.
Plant Physiol. 1995 Oct;109(2):611-8. doi: 10.1104/pp.109.2.611.
We have isolated a clone corresponding to a new cold-regulated gene from a cDNA library made from rapeseed (Brassica napus cv Samourai) cold-acclimated etiolated seedlings. Sequence analysis and homology searches showed that this clone encodes a protein highly homologous to the ATP-dependent phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.49) from Saccharomyces cerevisiae, Trypanosoma, Rhizobium sp., and Escherichia coli; we refer to the B. napus clone as BnPEPCK. A potential ATP-binding site existing in all PEPCK proteins was also found in BnPEPCK. Although there was a basal expression of BnPEPCK in seedlings grown at control, room temperature, the steady-state level of the transcripts increased at 4 degrees C and decreased to normal levels when the seedlings were returned to control temperature (22 degrees C). Using antibodies made against a recombinant histidine-BnPEPCK fusion protein, we demonstrated that BnPEPCK protein level is correlated with the accumulation of the BnPEPCK transcript.
我们从经低温驯化的油菜（甘蓝型油菜品种Samourai）黄化幼苗构建的cDNA文库中分离出了一个与新的冷调节基因相对应的克隆。序列分析和同源性搜索表明，该克隆编码一种与来自酿酒酵母、锥虫、根瘤菌属和大肠杆菌的ATP依赖性磷酸烯醇式丙酮酸羧激酶（PEPCK；EC 4.1.1.49）高度同源的蛋白质；我们将甘蓝型油菜克隆称为BnPEPCK。在BnPEPCK中也发现了所有PEPCK蛋白中存在的一个潜在ATP结合位点。虽然在对照室温下生长的幼苗中BnPEPCK有基础表达，但转录本的稳态水平在4℃时增加，当幼苗回到对照温度（22℃）时降至正常水平。使用针对重组组氨酸 - BnPEPCK融合蛋白制备的抗体，我们证明BnPEPCK蛋白水平与BnPEPCK转录本的积累相关。
