Department of Biological Sciences, Center for Plant Lipid Research, University of North Texas, Denton, TX 76203, USA.
Proc Natl Acad Sci U S A. 2010 Oct 12;107(41):17833-8. doi: 10.1073/pnas.0911359107. Epub 2010 Sep 27.
CGI-58 is the defective gene in the human neutral lipid storage disease called Chanarin-Dorfman syndrome. This disorder causes intracellular lipid droplets to accumulate in nonadipose tissues, such as skin and blood cells. Here, disruption of the homologous CGI-58 gene in Arabidopsis thaliana resulted in the accumulation of neutral lipid droplets in mature leaves. Mass spectroscopy of isolated lipid droplets from cgi-58 loss-of-function mutants showed they contain triacylglycerols with common leaf-specific fatty acids. Leaves of mature cgi-58 plants exhibited a marked increase in absolute triacylglycerol levels, more than 10-fold higher than in wild-type plants. Lipid levels in the oil-storing seeds of cgi-58 loss-of-function plants were unchanged, and unlike mutations in β-oxidation, the cgi-58 seeds germinated and grew normally, requiring no rescue with sucrose. We conclude that the participation of CGI-58 in neutral lipid homeostasis of nonfat-storing tissues is similar, although not identical, between plant and animal species. This unique insight may have implications for designing a new generation of technologies that enhance the neutral lipid content and composition of crop plants.
CGI-58 是一种称为 Chanarin-Dorfman 综合征的人类中性脂质贮积病的缺陷基因。这种疾病导致细胞内的脂质滴在非脂肪组织中积累，如皮肤和血细胞。在这里，拟南芥中同源 CGI-58 基因的破坏导致成熟叶片中中性脂质滴的积累。从 cgi-58 功能丧失突变体中分离的脂质滴的质谱分析表明，它们含有三酰基甘油，具有常见的叶特异性脂肪酸。成熟 cgi-58 植物的叶片表现出明显的绝对三酰基甘油水平增加，比野生型植物高 10 多倍。cgi-58 功能丧失植物的储油种子中的脂质水平没有变化，与β-氧化突变不同，cgi-58 种子发芽和正常生长，不需要用蔗糖进行挽救。我们得出结论，CGI-58 参与非脂肪组织中中性脂质稳态的作用在植物和动物物种之间是相似的，尽管不完全相同。这种独特的见解可能对设计新一代增强作物中性脂质含量和组成的技术具有重要意义。
