Overexpression of Heteromeric GhACCase Subunits Enhanced Oil Accumulation in Upland Cotton
Overexpression of Heteromeric GhACCase Subunits Enhanced Oil Accumulation in Upland Cotton
复制标题
异聚 GhACCase 亚基的过度表达增强陆地棉的油脂积累
DOI：
10.1007/s11105-016-1022-y
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发表时间：
2017-04-01
影响因子：
2.1
通讯作者：
Hua, Jinping
中科院分区：
文献类型：
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作者：
Cui, Yupeng;Liu, Zhengjie;Hua, Jinping
乙酰辅酶A羧化酶（ACCase）催化乙酰辅酶A产生丙二酰辅酶A，这是从头脂肪酸生物合成的重要第一步。陆地棉等高等植物的异聚ACCase由四个亚基组成：生物素羧基载体蛋白（BCCP）、生物素羧化酶（BC）、羧基转移酶α亚基（CTα）和羧基转移酶β亚基（CTβ）。在本研究中，扩增了编码异聚ACCase的四个亚基，并进一步分析了结构。结果显示，从GhBCCP1、GhBC1、GhCTα2和GhCTβ中分别鉴定出7、16、10和1个外显子。表达模式分析表明，这四个亚基的转录本普遍存在于所有测试组织中，并且这四个亚基与油脂积累之间可能存在正相关。四个亚基相互协调，提高含油量。 ABA、MeJA 处理和冷胁迫下表达模式和水平有所不同。此外，在种子特异性AGP启动子的控制下，陆地棉中四个亚基的过表达表明，GhBCCP1转基因植物的棉籽含油量显着增加了21.92％，而GhBC1和GhCTβ分别增加了约17％。因此异聚体GhACCase各亚基的过表达可以有效提高陆地棉籽油含量。
Acetyl-CoA carboxylase (ACCase) catalyzes acetyl-CoA to produce malonyl-CoA, which is the essential first step in the biosynthesis of de novo fatty acids. The heteromeric ACCase of higher plants, such as upland cotton, is composed of four subunits: biotin carboxyl carrier protein (BCCP), biotin carboxylase (BC), α-subunit of carboxyltransferase (CTα), and β-subunit of carboxyltransferase (CTβ). In this study, four subunits encoding heteromeric ACCase were amplified and the structures were analyzed further. The result showed that 7, 16, 10, and 1 exon(s) were identified from GhBCCP1, GhBC1, GhCTα2, and GhCTβ, respectively. The expression pattern analysis showed that the transcripts of these four subunits were ubiquitous in all the tested tissues and may have a positive correlation between the four subunits and oil accumulation. The four subunits coordinate to enhance oil content. The expression patterns and levels varied under ABA, MeJA treatments, and cold stress. Furthermore, under the control of a seed-specific AGP promoter, overexpression of the four subunits separately in Upland cotton demonstrated that GhBCCP1 transgenic plants showed a significant increase of 21.92% in oil content in cotton seeds, while about a 17% increase was noted for GhBC1 and GhCTβ, respectively. So overexpression of each subunit of heteromeric GhACCase may effectively increase seed oil content in Upland cotton.