Turner S R, Barratt D H, Casey R
John Innes Institute, Norwich, UK.
Plant Mol Biol. 1990 May;14(5):793-803. doi: 10.1007/BF00016512.
Rocket immunoelectrophoresis was used to measure the accumulation of storage proteins in developing cotyledons of two Pisum sativum (pea) genotypes, that were close to isogenic except for the nature of the allele at the r locus. There was a marked decrease in legumin accumulation in the rr (wrinkled-seeded) genotype compared to the RR (round-seeded) genotype. The accumulation of vicilin did not differ greatly between the two genotypes. Pulse-labelling studies indicated that the differences in rates of accumulation of legumin between the rr and RR genotypes were a consequence of differences in rates of protein synthesis. Measurements of relative amounts of specific mRNAs, using cDNA clones as probes, showed lower amounts of legumin mRNA in developing cotyledons of the rr, compared to the RR, genotype. Both vicilin mRNAs and convicilin mRNA, the latter of which shows a similar temporal pattern of expression to those of the major legumin species, are relatively unaffected by the nature of the allele at the r locus. Nuclear run-on transcription experiments indicated no differences in the rate of synthesis of legumin transcripts in the rr and RR near-isolines. The consequences of homozygosity for the r allele on storage protein mRNA levels in vitro may be mimicked by manipulating the sucrose concentration of the culture medium.
采用火箭免疫电泳法测定了两种豌豆（Pisum sativum）基因型发育中的子叶中贮藏蛋白的积累情况，这两种基因型除r位点等位基因的性质外几乎同基因。与RR（圆粒种子）基因型相比，rr（皱粒种子）基因型中的豆球蛋白积累显著减少。两种基因型之间豌豆球蛋白的积累差异不大。脉冲标记研究表明，rr和RR基因型之间豆球蛋白积累速率的差异是蛋白质合成速率差异的结果。使用cDNA克隆作为探针测量特定mRNA的相对量，结果显示，与RR基因型相比，rr基因型发育中的子叶中豆球蛋白mRNA的量较低。豌豆球蛋白mRNA和伴豌豆球蛋白mRNA（后者与主要豆球蛋白种类的表达具有相似的时间模式）相对不受r位点等位基因性质的影响。细胞核连续转录实验表明，rr和RR近等基因系中豆球蛋白转录本的合成速率没有差异。通过控制培养基的蔗糖浓度，可以模拟r等位基因纯合对体外贮藏蛋白mRNA水平的影响。
