Starch turnover is important for plant response to abiotic stresses and plastidic starch phosphorylase Pho1a is a key enzyme regulating starch metabolism. In this study, we identified Pho1a coding sequences in seven wild tuber-bearing potato species. In Solanum tuberosum cv. Nadezhda grown at normal conditions, Pho1a transcription was low; it was detected in stems, leaves, flowers, and roots. After harvest, Pho1a expression in tubers of 16 S. tuberosum cultivars was either absent or low but progressively increased during storage at +4 °C, which corresponded to an increase in the content of reducing sugars. In the leaves of both cultivated and wild potato species, exposure to short-term cold stress downregulated Pho1a expression, especially at night, and stimulated starch degradation, but there was no uniform diurnal pattern in Pho1a expression dynamics. These findings indicate that Pho1a may have different functions in storage and photosynthetic organs of potato.

中文翻译：

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低温对马铃薯和马铃薯叶片Pho1a淀粉磷酸化酶基因表达的相反影响。

淀粉周转对于植物对非生物胁迫的响应很重要，质体淀粉磷酸化酶Pho1a是调节淀粉代谢的关键酶。在这项研究中，我们确定了7个野生块茎马铃薯品种中Pho1a编码序列。在马铃薯中。Nadezhda在正常条件下生长，Pho1a转录低；它在茎，叶，花和根中被检测到。收获后，Pho1a在16 S. tuberosum块茎中的表达 品种不存在或较低，但在+4°C下储存期间逐渐增加，这对应于还原糖含量的增加。在栽培马铃薯和野生马铃薯的叶片中，短期的低温胁迫都下调了Pho1a的表达，特别是在晚上，并刺激了淀粉的降解，但是在Pho1a的表达动力学中没有统一的昼夜模式。这些发现表明，Pho1a在马铃薯的贮藏和光合器官中可能具有不同的功能。