Kirihara J A, Hunsperger J P, Mahoney W C, Messing J W
Waksman Institute, Rutgers, State University, Piscataway, NJ 08855.
Mol Gen Genet. 1988 Mar;211(3):477-84. doi: 10.1007/BF00425704.
A methionine-rich 10 kDa zein storage protein from maize was isolated and the sequence of the N-terminal 30 amino acids was determined. Based on the amino acid sequence, two mixed oligonucleotides were synthesized and used to probe a maize endosperm cDNA library. A full-length cDNA clone encoding the 10 kDa zein was isolated by this procedure. The nucleotide sequence of the cDNA clone predicts a polypeptide of 129 amino acids, preceded by a signal peptide of 21 amino acids. The predicted polypeptide is unique in its extremely high content of methionine (22.5%). The maize inbred line BSSS-53, which has increased seed methionine due to overproduction of this protein, was compared to W23, a standard inbred line. Northern blot analysis showed that the relative RNA levels for the 10 kDa zein were enhanced in developing seeds of BSSS-53, providing a molecular basis for the overproduction of the protein. Southern blot analysis indicated that there are one or two 10 kDa zein genes in the maize genome.
从玉米中分离出一种富含蛋氨酸的10 kDa玉米醇溶蛋白储存蛋白，并测定了其N端30个氨基酸的序列。根据氨基酸序列合成了两种混合寡核苷酸，并用于探测玉米胚乳cDNA文库。通过该方法分离出一个编码10 kDa玉米醇溶蛋白的全长cDNA克隆。该cDNA克隆的核苷酸序列预测出一个由129个氨基酸组成的多肽，前面有一个由21个氨基酸组成的信号肽。预测的多肽以其极高的蛋氨酸含量（22.5%）而独特。将因该蛋白过量产生而种子蛋氨酸含量增加的玉米自交系BSSS - 53与标准自交系W23进行比较。Northern印迹分析表明，BSSS - 53发育种子中10 kDa玉米醇溶蛋白的相对RNA水平升高，为该蛋白的过量产生提供了分子基础。Southern印迹分析表明，玉米基因组中有一或两个10 kDa玉米醇溶蛋白基因。
