REGULATION OF THE OSEM GENE BY ABSCISIC-ACID AND THE TRANSCRIPTIONAL ACTIVATOR VP1 - ANALYSIS OF CIS-ACTING PROMOTER ELEMENTS REQUIRED FOR REGULATION BY ABSCISIC-ACID AND VP1
REGULATION OF THE OSEM GENE BY ABSCISIC-ACID AND THE TRANSCRIPTIONAL ACTIVATOR VP1 - ANALYSIS OF CIS-ACTING PROMOTER ELEMENTS REQUIRED FOR REGULATION BY ABSCISIC-ACID AND VP1
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DOI：
10.1046/j.1365-313x.1995.07060913.x
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发表时间：
1995-06-01
期刊：
影响因子：
7.2
通讯作者：
HAMASUNA, S
中科院分区：
文献类型：
--
作者：
HATTORI, T;TERADA, T;HAMASUNA, S
分离到一个与小麦Em基因同源的水稻基因Osem，该基因编码水稻胚胎发育后期丰富的蛋白之一。该基因受脱落酸(ABA)和转录激活因子VP1的调控，参与了ABA调控的胚胎发育后期基因的表达。构建了由Osem启动子和细菌β-葡萄糖苷酸酶(GUS)基因组成的融合基因(Osem-GUS)，并利用悬浮培养的水稻细胞原生质体，通过与水稻VP1(OSVP1)基因表达载体(35S-Osvp1)的共转染，在瞬时表达系统中进行了检测。外加ABA和(OS)VP1的过度表达可强烈激活OSEM-GUS的表达(40~150倍)。Osem启动子有三个含有ACGTG的序列，分别是基序A、基序B和基序A‘，它们与先前在小麦Em和水稻Rab16中发现的脱落酸响应元件(Abre)相似。还有一个CATGCATG序列，被称为sph box，被证明是VP1对玉米花青素调节基因C1的调节所必需的。针对这些序列元件，对OSEM启动子在瞬时表达系统中的各种突变衍生物进行了检测。分析表明，Motif A不仅作为ABRE发挥功能，而且作为(OS)VP1调控所需的序列元件。
Osem, a rice gene homologous to the wheat Em gene, which encodes one of the late-embryogenesis abundant proteins was isolated. The gene was characterized with respect to control of transcription by abscisic acid (ABA) and the transcriptional activator VP1, which is involved in the ABA-regulated gene expression during late embryogenesis. A fusion gene (Osem-GUS) consisting of the Osem promoter and the bacterial beta-glucuronidase (GUS) gene was constructed and tested in a transient expression system, using protoplasts derived from a suspension-cultured line of rice cells, for activation by ABA and by cotransfection with an expression vector (35S-Osvp1) for the rice VP1 (OSVP1) cDNA. The expression of Osem-GUS was strongly (40- to 150-fold) activated by externally applied ABA and by over-expression of (OS)VP1. The Osem promoter has three ACGTG-containing sequences, motif A, motif B and motif A', which resemble the abscisic acid-responsive element (ABRE) that was previously identified in the wheat Em and the rice Rab16. There is also a CATGCATG sequence, which is known as the Sph box and is shown to be essential for the regulation by VP1 of the maize anthocyanin regulatory gene C1. Focusing on these sequence elements, various mutant derivatives of the Osem promoter in the transient expression system were assayed. The analysis revealed that motif A functions not only as an ABRE but also as a sequence element required for the regulation by (OS)VP1.