Comparative structural and functional characterization of sorghum and maize duplications containing orthologous myb transcription regulators of 3-deoxyflavonoid biosynthesis
Comparative structural and functional characterization of sorghum and maize duplications containing orthologous myb transcription regulators of 3-deoxyflavonoid biosynthesis
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DOI：
10.1007/s11103-005-3568-1
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发表时间：
2006-01-01
影响因子：
5.1
通讯作者：
Chopra, S
中科院分区：
文献类型：
--
作者：
Boddu, J;Jiang, CH;Chopra, S
对高粱黄籽基因组区域的序列分析表明，存在两个基因，其排列顺序为头尾朝向。两个重复的基因拷贝y1和y2被一个9.084 kbp的基因间区隔开，该基因间区主要由高度重复的序列组成。y1是功能拷贝，而y2可能代表假基因；在假定的y2编码区内有几个序列索引和重排。y1基因编码一个R2R3型Myb结构域蛋白，该蛋白调控3-脱氧类黄酮生物合成所需的查尔酮合成酶、查尔酮异构酶和二氢黄酮醇还原酶基因的表达。y1的表达可以在整个植株中观察到，它代表了玉米p1不同等位基因产生的表达模式的组合。对y1、y2及其玉米和大刍动物同源基因编码区和侧翼序列的比较序列分析显示，它们的局部重排和插入可能造成了调控区域的修改。这些微共线修饰可能是玉米和高粱花和营养组织中表达模式差异的原因。系统发育分析表明，高粱的y1和y2序列可能是由基因重复机制产生的，与玉米的p2和p1基因的重复在进化上是平行的。
Sequence characterization of the genomic region of sorghum yellow seed1 shows the presence of two genes that are arranged in a head to tail orientation. The two duplicated gene copies, y1 and y2 are separated by a 9.084 kbp intergenic region, which is largely composed of highly repetitive sequences. The y1 is the functional copy, while the y2 may represent a pseudogene; there are several sequence indels and rearrangements within the putative coding region of y2. The y1 gene encodes a R2R3 type of Myb domain protein that regulates the expression of chalcone synthase, chalcone isomerase and dihydroflavonol reductase genes required for the biosynthesis of 3-deoxyflavonoids. Expression of y1 can be observed throughout the plant and it represents a combination of expression patterns produced by different alleles of the maize p1. Comparative sequence analysis within the coding regions and flanking sequences of y1, y2 and their maize and teosinte orthologs show local rearrangements and insertions that may have created modified regulatory regions. These micro-colinearity modifications possibly are responsible for differential patterns of expression in maize and sorghum floral and vegetative tissues. Phylogenetic analysis indicates that sorghum y1 and y2 sequences may have arisen by gene duplication mechanisms and represent an evolutionarily parallel event to the duplication of maize p2 and p1 genes.