Department of Biology, Virginia Polytechnic Institute and State University, 24061, Blacksburg, VA, USA.
Plant Mol Biol. 1987 Sep;9(5):421-30. doi: 10.1007/BF00015874.
A 23.8-kD alpha-zein polypeptide, K55PC7, has been shown to be a truncated member of the 26.7-kD alpha-zein class based on its amino acid composition, N-terminal sequence, and immunological properties. This unusual polypeptide was isolated by chromatographing whole alpha-zein from inbred K55. The N-terminal sequence of K55PC7 is highly homologous to those of 4 putative 26.7-kD alpha-zeins but shows no homology to those of 10 putative alpha-zeins that belong to the 23.8-kD class. Its higher valine and lower phenylalanine contents also suggest that K55PC7 is a member of the 26.7-kD class. In addition, studies with antibodies raised to peptides corresponding to regions unique to each of the two alpha-zein classes indicate that K55PC7 has immunological similarity to 26.7-kD alpha-zeins. Peptide mapping data suggest that K55PC7 is not the putative product of the truncated 26.7-kD alpha-zein gene zA1 isolated from inbred W64A and described by Spena et al. [26]. It appears that K55PC7 occurs as a major component in inbred K55 and is a truncated version of a 26.7-kD alpha-zein, arisen either by an internal deletion or premature termination due to a nonsense mutation.
一种 23.8kDa 的α-zein 多肽 K55PC7，基于其氨基酸组成、N 端序列和免疫特性，被证明是 26.7kDa α-zein 类的截断成员。这种不寻常的多肽是通过从近交系 K55 中色谱分离全α-zein 而分离得到的。K55PC7 的 N 端序列与 4 种假定的 26.7kDa α-zein 高度同源，但与属于 23.8kDa 类的 10 种假定的α-zein 没有同源性。其较高的缬氨酸和较低的苯丙氨酸含量也表明 K55PC7 是 26.7kDa 类的成员。此外，用针对两种α-zein 类特有的区域的肽产生的抗体进行的研究表明，K55PC7 与 26.7kDa α-zein 具有免疫相似性。肽图谱数据表明，K55PC7 不是 Spena 等人[26]从近交系 W64A 中分离并描述的截断 26.7kDa α-zein 基因 zA1 的假定产物。似乎 K55PC7 作为近交系 K55 的主要成分存在，并且是 26.7kDa α-zein 的截断版本，可能是由于内部缺失或由于无意义突变导致的过早终止而产生的。
