Zrenner R, Willmitzer L, Sonnewald U
Institut für Genbiologische Forschung Berlin GmbH, FRG.
Planta. 1993;190(2):247-52. doi: 10.1007/BF00196618.
The expression of the enzyme UDP-glucose pyrophosphorylase (UGPase; EC 2.7.7.9) from potato (Solanum tuberosum L.) was analysed with respect to sink-source interactions and potato tuber storage. The highest level of expression was found in developing tubers, the strongest sink tissue. Storage of mature tubers at low temperatures led to an increase of the steady-state level of UGPase mRNA, implicating a role of this enzyme in the process of "cold-sweetening". Transgenic plants were created expressing UGPase antisensee RNA under the control of the 35S promoter of the Cauliflower Mosaic Virus with the polyadenylation signal of the octopine-synthase gene. Regenerated plants were tested for reduction of UGPase at the RNA, protein and activity levels. Plants with a 95%-96% reduction of UGPase activity in growing tubers showed no change in growth and development. Also, carbohydrate metabolism in tubers of these plants was not substantially affected, indicating that only 4% of the wild-type UGPase activity is sufficient for the enzyme to function in plant growth and development.
针对库源相互作用和马铃薯块茎贮藏，对马铃薯（Solanum tuberosum L.）中UDP - 葡萄糖焦磷酸化酶（UGPase；EC 2.7.7.9）的表达进行了分析。在发育中的块茎（最强的库组织）中发现了最高水平的表达。将成熟块茎低温贮藏导致UGPase mRNA的稳态水平增加，这表明该酶在“冷糖化”过程中发挥作用。利用花椰菜花叶病毒的35S启动子和章鱼碱合酶基因的多聚腺苷酸化信号，创建了表达UGPase反义RNA的转基因植物。对再生植株在RNA、蛋白质和活性水平上UGPase的减少情况进行了检测。在生长的块茎中UGPase活性降低95% - 96%的植株，其生长和发育没有变化。此外，这些植株块茎中的碳水化合物代谢也没有受到实质性影响，这表明野生型UGPase活性的仅4%就足以使该酶在植物生长和发育中发挥作用。
