Nagy F, Boutry M, Hsu M Y, Wong M, Chua N H
Laboratory of Plant Molecular Biology, Rockefeller University, New York, NY 10021-6399.
EMBO J. 1987 Sep;6(9):2537-42. doi: 10.1002/j.1460-2075.1987.tb02541.x.
We have previously reported that the expression of the wheat Cab-1 gene is subject to phytochrome regulation and a 1.8-kb 5' upstream sequence of this gene is sufficient for the regulated expression. To delineate sequences for the phytochrome response we analyzed a series of 5' deletion mutants as well as chimeric gene constructs comprising different sequences of the Cab-1 upstream region in transgenic tobacco seedlings. We found that a deletion mutant containing a 357-bp 5' upstream sequence still exhibits maximal levels of phytochrome-regulated expression. A 268-bp enhancer-like element, located between -89 and -357, is responsible for the phytochrome response of the Cab-1 gene; sequences upstream from -357 to -843 and downstream from -124 to +1100 are probably not involved. Finally, we show that the Cab-1 mRNA stability is not regulated by phytochrome.
我们之前报道过，小麦Cab-1基因的表达受光敏色素调控，该基因1.8 kb的5'上游序列足以实现调控表达。为了确定光敏色素应答的序列，我们分析了一系列5'缺失突变体以及包含Cab-1上游区域不同序列的嵌合基因构建体，这些构建体存在于转基因烟草幼苗中。我们发现，一个含有357 bp 5'上游序列的缺失突变体仍表现出光敏色素调控表达的最高水平。位于-89至-357之间的一个268 bp的增强子样元件负责Cab-1基因的光敏色素应答；-357至-843上游以及-124至+1100下游的序列可能不参与其中。最后，我们表明Cab-1 mRNA的稳定性不受光敏色素调控。
