Dynamics of neutral lipid storage and mobilization in yeast
Dynamics of neutral lipid storage and mobilization in yeast
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DOI：
10.1016/j.biochi.2006.06.018
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发表时间：
2007-02-01
期刊：
影响因子：
3.9
通讯作者：
Athenstaedt, K.
中科院分区：
文献类型：
--
作者：
Daum, G.;Wagner, A.;Athenstaedt, K.
我们利用酿酒酵母作为一个灵活的实验系统，研究协调途径的中性脂质的合成，储存和动员，特别强调在这些过程中的作用，不同的细胞器。最近，一些新的基因产物参与三酰甘油（TAG）和甾醇酯（STE）代谢被确定在我们的实验室和其他团体。STE由两种STE酶Arelp和Are2p合成，而TAG主要通过两种TAG酶Dga1p和Lro1p的作用形成，Are1p和Are2p的贡献较小。一旦形成，TAG和STE储存在所谓的脂质颗粒中。缺乏中性脂质合成，因此缺乏脂质颗粒的dga 1，Delta ro 1 Delta are1 Delta are2 Delta四重突变体被证明是用于研究储存脂质和脂质颗粒的生理作用的有价值的工具。通过TAG脂肪酶和STE水解酶的催化，中性脂质贮库发生动员。最近在分子水平上鉴定了三种TAG脂肪酶Tg13p、Tg14p和Tg15p，以及三种STE水解酶Tg11p、Yeh1p和Yeh2p。虽然这些水解酶在酶家族内表现出重叠的功能，但它们分别对TAG和STE具有特异性。除了Dgalp（其活性部分定位于脂质颗粒）之外，TAG和STE形成酶限于内质网。TAG脂肪酶和STE水解酶是脂质颗粒的组分，除了位于质膜的Yeh2p。因此，中性脂质代谢不仅在酶水平上受到调节，而且还通过将组分分配到细胞器来调节。中性脂质体内平衡与许多细胞生物学过程相关的事实证实了这类脂质作为细胞调节剂或效应物的重要作用。(c)2006年，Elsevier Masson SAS。All rights reserved.
We make use of the yeast Saccharonzyces cerevisiae as a flexible experimental system to investigate coordinate pathways of neutral lipid synthesis, storage and mobilization with special emphasis on the role of different organelles in these processes. Recently, a number of new gene products involved in triacylglycerol (TAG) and steryl ester (STE) metabolism were identified in our laboratory and by other groups. STE are synthesized by the two STE synthases Arelp and Are2p, whereas TAG are formed mainly through the action of the two TAG synthases Dga1p and Lro1p with minor contributions of Are1p and Are2p. Once formed, TAG and STE are stored in so-called lipid particles. A dga1,Delta ro1 Delta are1 Delta are2 Delta quadruple mutant which lacks neutral lipid synthesis and is consequently devoid of lipid particles turned out to be a valuable tool for studying the physiological role of storage lipids and lipid particles. Mobilization of neutral lipid depots occurs through catalysis of TAG lipases and STE hydrolases. Three TAG lipases named Tg13p, Tg14p and Tg15p, and three STE hydrolases named Tg11p, Yeh1p and Yeh2p were recently identified at the molecular level. Although these hydrolases exhibit overlapping function within the enzyme families, they are specific for TAG and STE, respectively. With the exception of Dgalp, whose activity is partially localized to lipid particles, TAG and STE forming enzymes are restricted to the endoplasmic reticulum. TAG lipases and STE hydrolases are components of lipid particles with the exception of Yeh2p, which is plasma membrane located. Thus, neutral lipid metabolism is not only regulated at the enzyme level but also by the distribution of the components to organelles. The fact that neutral lipid homeostasis is linked to a number of cell biological processes confirms the important role of this class of lipids as cellular modulators or effectors. (c) 2006 Elsevier Masson SAS. All rights reserved.