Cloning and characterisation of two genes for 3-hydroxy-3-methylglutaryl coenzyme A reductase and their possible roles during fruit development in Dimocarpus longan
Cloning and characterisation of two genes for 3-hydroxy-3-methylglutaryl coenzyme A reductase and their possible roles during fruit development in Dimocarpus longan
复制标题
龙眼 3-羟基-3-甲基戊二酰辅酶 A 还原酶两个基因的克隆和表征及其在龙眼果实发育中的可能作用
DOI：
10.1080/14620316.2011.11512720
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发表时间：
2011-01
影响因子：
1.9
通讯作者：
Xia, Rui
中科院分区：
文献类型：
--
作者：
Lu, Wang-Jin;Li, Jian-Guo;Wang, Ze-Huai;Xia, Rui
摘要 3-羟基-3-甲基戊二酰辅酶 A 还原酶（HMGR；EC：1.1.1.34）由真核生物中的多个基因编码，已知可催化类异戊二烯生物合成的甲羟戊酸 (MVA) 途径中的第一个关键步骤，并与果实大小的测定有关。为了阐明 HMGR 基因是否参与龙眼 (Dimocarpus longan) 果实生长的调节，我们克隆了两个序列不同的 HMGR 基因，分别命名为 DlHMG1 和 DlHMG2。序列分析表明，它们具有高水平的序列和结构域保守性，并在其他物种中在核苷酸和氨基酸水平上鉴定出同源物。基因表达分析表明，这两个基因在果皮、假种皮、种子以及果实发育过程中受到差异性调控。 DlHMG1 特别是在 I 期 [花后 0 – 42 d (DAA)] 和 II 期早期 (42 – 56 DAA) 上调，随后在 III 期 (≥ 56 DAA) 下调；而DlHMG2在果皮和假种皮中组成型表达，但在果实发育过程中在种子组织中周期性波动。讨论了 DlHMG1 和 DlHMG2 在调节龙眼果实大小和生长中的可能作用。
Summary 3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGR; EC: 1.1.1.34), encoded by multiple genes in eukaryotes, is known to catalyse the first committed step in the mevalonic acid (MVA) pathway for the biosynthesis of isoprenoids, and has been implicated in fruit size determination. To elucidate whether the genes for HMGR are involved in the regulation of fruit growth in longan (Dimocarpus longan), we cloned two sequence-distinct HMGR genes, designated DlHMG1 and DlHMG2, respectively. Sequence analyses revealed that they shared a high level of sequence and domain conservation, with homologues identified in other species at both the nucleotide and amino acid levels. Gene expression analysis showed that the two genes were differentially regulated in the pericarp, arils, and seed, as well as during fruit development. DlHMG1 was up-regulated particularly in Phase I [0 – 42 d after anthesis (DAA)] and at the early stage of Phase II (42 – 56 DAA), followed by down-regulation in Phase III (≥ 56 DAA); while DlHMG2 was expressed constitutively in the pericarp and arils, but fluctuated periodically in seed tissues during fruit development. The possible roles of DlHMG1 and DlHMG2 in the regulation of longan fruit size and growth are discussed.