Hendriks T, Vreugdenhil D, Stiekema W J
Department of Molecular Biology, Centre for Plant Breeding Research CPO, Wageningen, Netherlands.
Plant Mol Biol. 1991 Sep;17(3):385-94. doi: 10.1007/BF00040633.
A highly efficient and synchronous in vitro tuberization system is described. One-node stem pieces from potato (Solanum tuberosum cv. Bintje) plants grown under short day-light conditions containing an axillary bud were cultured in the dark on a tuber-inducing medium. After 5 or 6 days all axillary buds started to develop tubers. To study gene expression during tuber development, RNA isolated from tuberizing axillary buds was used for both in vitro translation and northern blot hybridizations. The genes encoding the proteinase inhibitors I and II (PI-I and PI-II), a Kunitz- and a Bowman-Birk-type proteinase inhibitor were already expressed in uninduced axillary buds. The length of the day-light conditions differently influenced the expression level of the individual genes. In addition, the expression of each of these genes changed specifically during the development of the axillary bud to tuber. In contrast to the expression of these proteinase inhibitor genes, patatin gene expression was only detectable from the day tuberization was manifested as a radial expansion of the axillary bud. These results are discussed with respect to the regulation of the expression of the genes studied in relation to the regulation of tuber development.
本文描述了一种高效且同步的体外块茎形成系统。将在短日照条件下生长的马铃薯（Solanum tuberosum cv. Bintje）植株带有腋芽的单节茎段在黑暗中培养于块茎诱导培养基上。5或6天后，所有腋芽开始发育形成块茎。为了研究块茎发育过程中的基因表达，从正在形成块茎的腋芽中分离的RNA用于体外翻译和Northern印迹杂交。编码蛋白酶抑制剂I和II（PI-I和PI-II）、一种Kunitz型和一种Bowman-Birk型蛋白酶抑制剂的基因在未诱导的腋芽中就已表达。日照条件的时长对各个基因的表达水平有不同影响。此外，这些基因中的每一个在腋芽发育成块茎的过程中表达都有特异性变化。与这些蛋白酶抑制剂基因的表达不同，仅从块茎形成表现为腋芽径向扩展的当天起才能检测到马铃薯块茎蛋白基因的表达。本文就所研究基因的表达调控与块茎发育调控的关系对这些结果进行了讨论。
