Roesler K R, Shorrosh B S, Ohlrogge J B
Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824.
Plant Physiol. 1994 Jun;105(2):611-7. doi: 10.1104/pp.105.2.611.
Acetyl-coenzyme A carboxylase (ACCase) catalyzes the formation of malonyl-coenzyme A, which is used in the plastid for fatty acid synthesis and in the cytosol for several pathways including fatty acid elongation and flavonoid synthesis. Two overlapping Arabidopsis genomic clones were isolated and sequenced to determine the entire ACCase-coding region. Thirty introns with an average size of 94 bp were identified by comparison with an alfalfa ACCase cDNA sequence. The 10-kb Arabidopsis ACCase gene encodes a 251-kD polypeptide, which has 80% amino acid sequence identity with alfalfa ACCase and about 40% identity with ACCase of rat, chicken, yeast, and the diatom Cyclotella. No chloroplast transit peptide sequence was observed, suggesting that this Arabidopsis gene encodes a cytosolic ACCase isozyme. ACCase gene transcripts were detected by RNase protection assays in Arabidopsis root, leaf, silique, and seed. Genomic DNA blot analysis revealed the presence of a second related Arabidopsis ACCase gene.
乙酰辅酶A羧化酶（ACCase）催化丙二酰辅酶A的形成，丙二酰辅酶A在质体中用于脂肪酸合成，在细胞质中用于包括脂肪酸延长和类黄酮合成在内的多种途径。分离并测序了两个重叠的拟南芥基因组克隆，以确定整个ACCase编码区。通过与苜蓿ACCase cDNA序列比较，鉴定出30个平均大小为94 bp的内含子。10 kb的拟南芥ACCase基因编码一个251 kD的多肽，其与苜蓿ACCase的氨基酸序列同一性为80%，与大鼠、鸡、酵母和硅藻小环藻的ACCase的同一性约为40%。未观察到叶绿体转运肽序列，表明该拟南芥基因编码一种细胞质ACCase同工酶。通过核糖核酸酶保护试验在拟南芥根、叶、角果和种子中检测到ACCase基因转录本。基因组DNA印迹分析显示存在第二个相关的拟南芥ACCase基因。
