Campos N, Schell J, Palme K
Max-Planck-Institut für Züchtungsforschung, Köln, F.R.G.
Plant Cell Physiol. 1994 Mar;35(2):153-61.
We have analyzed auxin-binding proteins from maize encoded by the Zm-ERabp gene family. Open reading frames of cDNA clones predict proteins containing N-terminal hydrophobic signal sequences. In vitro studies show that the Zm-ERabp1 protein can be translocated into ER-derived microsomes where it is processed and glycosylated. A cDNA clone encoding the Zm-ERabp4 protein predicts an open reading frame with a signal sequence that shows striking differences in charge distribution, in comparison to the signal sequence of Zm-ERabp1. Two translation products are synthesized from the Zm-ERabp4 transcript in the in vitro system, but only one of them is translocated into maize endosperm microsomes, indicating that specific cotranslational modifications in the primary sequence remaining after processing may play a role in the cellular trafficking of the Zm-ERabp4 protein.
我们已经分析了由Zm-ERabp基因家族编码的玉米生长素结合蛋白。cDNA克隆的开放阅读框预测蛋白质含有N端疏水信号序列。体外研究表明，Zm-ERabp1蛋白可以转运到内质网衍生的微粒体中，在那里它被加工和糖基化。编码Zm-ERabp4蛋白的cDNA克隆预测了一个带有信号序列的开放阅读框，与Zm-ERabp1的信号序列相比，该信号序列在电荷分布上有显著差异。在体外系统中，Zm-ERabp4转录本合成了两种翻译产物，但只有其中一种被转运到玉米胚乳微粒体中，这表明加工后一级序列中的特定共翻译修饰可能在Zm-ERabp4蛋白的细胞运输中起作用。
