Characterization of a deletion allele of a sorghum Myb gene, yellow seed1 showing loss of 3-deoxyflavonoids
Characterization of a deletion allele of a sorghum Myb gene, yellow seed1 showing loss of 3-deoxyflavonoids
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DOI：
10.1016/j.plantsci.2005.05.007
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发表时间：
2005-09-01
期刊：
影响因子：
5.2
通讯作者：
Chopra, S
中科院分区：
文献类型：
--
作者：
Boddu, J;Svabek, C;Chopra, S
在高粱中，成熟种子果皮中观察到的3-脱氧黄酮类色素或苯酚是由黄烷-4-醇通过黄酮类生物合成途径获得的。我们在这里表明，苯酚在果皮、颖片和叶片中的积累与功能基因黄籽1(Y1)有关。对品系BTx623中的y1功能缺失等位基因进行了分子和遗传分析。该高粱品系不会在果皮、颖片和叶片中积累任何可检测到的黄烷-4-醇或可见的邻苯二酚水平。Y1[BTx623]的分子结构缺失3218个碱基，去除了5‘非编码启动子、外显子1、内含子1、外显子2和部分内含子2序列。被命名为y1-ww(白色果皮，白色颖片)的空的y1等位基因没有被转录，这导致了Y1调控的结构基因的表达，这些基因是黄烷-4-醇生物合成所需的。此外，对一种功能等位基因的种子提取物进行LC-MS分析，发现存在被称为3-脱氧花青素的正电荷化合物。鉴定的化合物为芹菜素、叶黄素和芹菜素的甲氧基化衍生物。BTx623种子提取物中未检测到Se化合物。以前的研究表明，高粱叶片中的3-脱氧花青素被炭疽菌(Colletotrichum Subineolum)诱导产生。我们的结果现在为高粱中可能导致黄烷-4-醇和3-脱氧花青素的生物合成的共同的类黄酮途径提供了证据。(C)2005爱思唯尔爱尔兰有限公司。保留所有权利。
In sorghum, 3-deoxyflavonoid pigments or phlobaphenes observed in the pericarp, of mature seed are derived from flavan-4-ols through the flavonoid biosynthetic pathway. We show here that phlobaphenes accumulation in pericarp, glumes and leaves is genetically linked with the functional yellow seed1 (y1) gene. Molecular and genetic analysis was performed on a loss of function allele of y1 present in the line BTx623. This sorghum line does not accumulate any detectable levels of flavan-4-ols or visible phlobaphenes in pericarp, glumes and leaves. Molecular structure of the y1 [BTx623] showed a deletion of 3218 bp which removes 5' non-coding, putative promoter, exon 1, intron 1, exon2, and part of the intron2 sequences. The null y1 allele designated as y1-ww (white pericarp, white glume) is not transcribed and this results in a loss of Y1-regulated expression of structural genes needed for the biosynthesis of flavan-4-ols. Further LC-MS analysis of seed extracts of a functional yl allele detected the presence of positively charged compounds known as 3-deoxyanthocyanidins. Compounds identified were apigeninidin, luteolinidin, and a methoxylated derivative of apigeninidin. The se compounds were not detected in BTx623 seed extracts. Previous studies have shown that 3-deoxyanthocyanidins are induced in sorghum leaves challenged with Colletotrichum sublineolum, a fungus that causes anthracnose in sorghum. Our results now provide an evidence for a common flavonoid pathway that may lead to the biosynthesis of flavan-4-ols and 3-deoxyanthocyanidins in sorghum. (c) 2005 Elsevier Ireland Ltd. All rights reserved.