Hallmann A, Sumper M
Lehrstuhl Biochemie I, Universität Regensburg, Germany.
Proc Natl Acad Sci U S A. 1994 Nov 22;91(24):11562-6. doi: 10.1073/pnas.91.24.11562.
The multicellular alga Volvox is an attractive model for the study of developmental processes. With the recent report of successful transformation, regulated promoters as well as reporter genes working in this organism are now required. The Volvox genes encoding arylsulfatase and the extracellular glycoprotein ISG are strictly regulated. The former is transcribed only under conditions of sulfur starvation, whereas the latter operates under extreme developmental control--i.e., it is transcribed for only a few minutes in Volvox embryos at the stage of embryonic inversion. The gene encoding the sexual pheromone of Volvox carteri was placed under the control of the arylsulfatase promoter. In response to sulfur deprivation, V. carteri transformed by this construct synthesized and secreted biologically active pheromone. In addition, the gene encoding Volvox arylsulfatase was placed under the control of the ISG promoter. Transformed algae synthesized arylsulfatase mRNA only during embryonic inversion. These experiments demonstrate the usefulness of both the arylsulfatase and the sexual pheromone reporter genes. In addition, the highly regulated arylsulfatase promoter allows the construction of inducible expression vectors for cloned genes.
多细胞藻类团藻是研究发育过程的一个有吸引力的模型。随着最近成功转化的报道，现在需要在这种生物体中起作用的调控启动子以及报告基因。团藻中编码芳基硫酸酯酶和细胞外糖蛋白ISG的基因受到严格调控。前者仅在硫饥饿条件下转录，而后者在极端发育控制下发挥作用——也就是说，它在团藻胚胎反转阶段仅转录几分钟。将编码卡特团藻性信息素的基因置于芳基硫酸酯酶启动子的控制之下。响应于硫剥夺，用该构建体转化的卡特团藻合成并分泌具有生物活性的信息素。此外，将编码团藻芳基硫酸酯酶的基因置于ISG启动子的控制之下。转化的藻类仅在胚胎反转期间合成芳基硫酸酯酶mRNA。这些实验证明了芳基硫酸酯酶和性信息素报告基因的有用性。此外，高度调控的芳基硫酸酯酶启动子允许构建用于克隆基因的诱导型表达载体。
