Kodrzycki R, Boston R S, Larkins B A
Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907.
Plant Cell. 1989 Jan;1(1):105-14. doi: 10.1105/tpc.1.1.105.
Zeins, the storage proteins of maize seed, are encoded by a large multigene family that is regulated developmentally and expressed in a tissue-specific manner during endosperm development. The synthesis of these proteins is affected by mutations, such as opaque-2, that cause a reduction in the accumulation of zein proteins and mRNAs. We used nuclear run-on transcription assays to analyze the expression of zein genes in developing normal and opaque-2 endosperms and to map the origin of these transcripts with respect to the coding and noncoding regions of the genes. These analyses demonstrate that zein gene expression is regulated transcriptionally and posttranscriptionally in developing endosperm. Transcription of genes encoding alpha-zeins is inhibited significantly in opaque-2 mutants, with expression of those encoding the M(r) 22,000 proteins being almost totally blocked. Other gene subfamilies were affected but to a lesser extent.
醇溶蛋白是玉米种子的贮藏蛋白，由一个庞大的多基因家族编码，该家族在胚乳发育过程中受到发育调控并以组织特异性方式表达。这些蛋白质的合成受突变（如不透明-2）的影响，这些突变会导致醇溶蛋白和mRNA的积累减少。我们使用核转录分析来分析醇溶蛋白基因在正常发育和不透明-2胚乳中的表达，并根据基因的编码区和非编码区来定位这些转录本的起源。这些分析表明，醇溶蛋白基因的表达在发育中的胚乳中受到转录和转录后调控。在不透明-2突变体中，编码α-醇溶蛋白的基因转录受到显著抑制，编码分子量为22,000蛋白质的基因表达几乎完全被阻断。其他基因亚家族也受到影响，但程度较小。
