Small G M, Szabo L J, Lazarow P B
Rockefeller University, New York, NY 10021.
EMBO J. 1988 Apr;7(4):1167-73. doi: 10.1002/j.1460-2075.1988.tb02927.x.
Acyl-CoA oxidase is a major induced enzyme in peroxisomes of Candida tropicalis grown on fatty acids. The gene, POX4, encoding acyl-CoA oxidase was expressed in vitro, and the resulting polypeptide was imported into purified peroxisomes in a temperature-dependent fashion. Plasmids containing fragments of POX4 were prepared, expressed and the polypeptides tested for import into peroxisomes. We identified two regions of acyl-CoA oxidase (amino acids 1-118 and 309-427) that contained information that specifically targeted fragments of acyl-CoA oxidase to peroxisomes. The corresponding regions of the gene were fused to cDNA encoding the cytosolic enzyme dihydrofolate reductase (DHFR), and the expressed fusion proteins were likewise imported into peroxisomes. DHFR itself neither bound to, nor was imported into peroxisomes. Thus, there are at least two regions of peroxisomal targeting information in the acyl-CoA oxidase gene.
酰基辅酶A氧化酶是热带假丝酵母在脂肪酸上生长时过氧化物酶体中的一种主要诱导酶。编码酰基辅酶A氧化酶的基因POX4在体外表达，产生的多肽以温度依赖的方式导入纯化的过氧化物酶体。制备了含有POX4片段的质粒，进行表达，并测试所得多肽导入过氧化物酶体的情况。我们鉴定出酰基辅酶A氧化酶的两个区域（氨基酸1 - 118和309 - 427），它们包含将酰基辅酶A氧化酶片段特异性靶向过氧化物酶体的信息。该基因的相应区域与编码胞质酶二氢叶酸还原酶（DHFR）的cDNA融合，表达的融合蛋白同样被导入过氧化物酶体。DHFR本身既不与过氧化物酶体结合，也不被导入过氧化物酶体。因此，酰基辅酶A氧化酶基因中至少有两个过氧化物酶体靶向信息区域。
