稻瘟病菌过氧化物酶体产生与降解的关键基因

Key Genes in Peroxisome Biogenesis and Degradation in Magnaporthe oryzae

过氧化物酶体(peroxisomes)是真核细胞中一类单层膜包被的细胞器,参与多种生化代谢.过氧化物酶体起源于内质网,过氧化物酶体形成相关的蛋白称为Peroxin,其编码基因通常写作PEX.细胞中过氧化物酶体的选择性消解称为过氧化物酶体自噬(pexophagy).参与细胞自噬(autophagy)的基因(ATG)大多参与过氧化物酶体自噬.近年来,丝状真菌中过氧化物酶体形成与降解机制的研究进展迅速,相关基因不断被鉴定.本文对相关研究进行了简要评述,并以稻瘟病菌为例,对丝状真菌基因组中可能的PEX和ATG基因进行了检索.发现稻瘟病菌中存在除PEX15,PEX17,PEX18,PEX21,PEX22,ATG19,ATG25,ATG30和ATG31之外的大多数PEX和ATG基因;同时,还存在多个丝状真菌特有的基因.说明过氧化物酶体的产生与消解在酵母、丝状真菌与哺乳动物之间相对保守,同时又各具特性.

Peroxisomes are singlemembrane surrounded organelles involved in various metabolisms in eukaryotic cells. Peroxisomes originate in the endoplasmic reticulum, respond to environmental changes, and degrade via pexophagy, which is an autophagic pathway specific for peroxisomes regulated by ATG genes. Proteins involved in peroxisome biogenesis are encoded by PEX genes, called peroxin. In recent years, advances have been made in the understanding of peroxisomal biogenesis and pexophagy in filamentous fungi. We retrieved the homologues of PEX and ATG in Magnaporthe oryzae. Except for PEX15, PEX17, PEX18, PEX21, PEX22, ATG19, ATG25, ATG30 and ATG31, most of PEX and ATG genes were detected, together with other fugal specific genes. These findings indicated that peroxisomal biogenesis and degradation were generally conserved from yeasts, filamentous fungi to mammals, but with differences specific to organism types.