School of Life Sciences, University of Hyderabad, 500 134, Hyderabad, India.
Theor Appl Genet. 1988 Sep;76(3):381-4. doi: 10.1007/BF00265337.
The etched (et) mutation in maize causes distinct depressions and structural gaps in the endosperm and also gives rise to virescent seedlings, α- and β-Amylase activities were observed to be higher in et (+) et (+) kernels and seedlings as compared to that of the et et mutant. The total amylase and β-amylase trends during germination also differed between normal and mutant kernels and seedlings (it increases in the wildtype and decreases in et et). On the contrary, the overall α-amylase trend was found to be similar in both genotypes (slight decrease during germination). The native gel electrophoresis of crude enzyme extracts did not reveal any qualitative differences in α and β amylases during germination. The germinating et et kernels initially showed lower levels of starch compared with the wild type kernels, whereas no such difference was found at later stages of germination. It is concluded that et gene associated endosperm lesions lead to an impairment of starch degradation in germinating kernels resulting in virescent seedlings.
玉米中的蚀变(et)突变导致胚乳中出现明显的凹陷和结构间隙,并导致幼苗呈淡绿色。与 et et 突变体相比,et(+)et(+)胚乳和幼苗中的α-和β-淀粉酶活性更高。在萌发过程中,总淀粉酶和β-淀粉酶的趋势也在正常和突变的胚乳和幼苗之间有所不同(在野生型中增加,在 et et 中减少)。相反,发现两种基因型的整体α-淀粉酶趋势相似(在萌发过程中略有下降)。粗酶提取物的天然凝胶电泳在萌发过程中没有显示α和β淀粉酶的任何定性差异。与野生型胚乳相比,萌发的 et et 胚乳最初显示出较低水平的淀粉,而在萌发的后期阶段则没有发现这种差异。结论是,与 et 基因相关的胚乳损伤导致萌发胚乳中淀粉降解受损,从而导致幼苗呈淡绿色。