HIGH STEROL ESTER 1 is a key factor in plant sterol homeostasis

编号 040021605

推送时间 20191209

研究领域 森林培育 

年份 2019 

类型 期刊 

语种 英语

标题 HIGH STEROL ESTER 1 is a key factor in plant sterol homeostasis

来源期刊 Nature Plants

期 第216期

发表时间 20191111

关键词 high sterol ester 1 (hise1);  sterol homeostasis;  endoplasmic reticulum (ER);  phospholipid sterol acyltransferase1 (PSAT1); 

摘要 Plants strictly regulate the levels of sterol in their cells, as high sterol levels are toxic. However, how plants achieve sterol homeostasis is not fully understood. We isolated an Arabidopsis thaliana mutant that abundantly accumulated sterol esters in structures of about 1?μm in diameter in leaf cells. We designated the mutant high sterol ester 1 (hise1) and called the structures sterol ester bodies. Here, we show that HISE1, the gene product that is altered in this mutant, functions as a key factor in plant sterol homeostasis on the endoplasmic reticulum (ER) and participates in a fail-safe regulatory system comprising two processes. First, HISE1 downregulates the protein levels of the β-hydroxy β-methylglutaryl-CoA reductases HMGR1 and HMGR2, which are rate-limiting enzymes in the sterol synthesis pathway, resulting in suppression of sterol overproduction. Second, if the first process is not successful, excess sterols are converted to sterol esters by phospholipid sterol acyltransferase1 (PSAT1) on ER microdomains and then segregated in SE bodies.

服务人员 孙小满

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