Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA.
Department of Molecular Biology, University of California San Diego, La Jolla, CA, USA.
J Lipid Res. 2024 Oct;65(10):100643. doi: 10.1016/j.jlr.2024.100643. Epub 2024 Sep 18.
Mitochondrial membranes are defined by their diverse functions, complex geometries, and unique lipidomes. In the inner mitochondrial membrane, highly curved membrane folds known as cristae house the electron transport chain and are the primary sites of cellular energy production. The outer mitochondrial membrane is flat by contrast, but is critical for the initiation and mediation of processes key to mitochondrial physiology: mitophagy, interorganelle contacts, fission and fusion dynamics, and metabolite transport. While the lipid composition of both the inner mitochondrial membrane and outer mitochondrial membrane have been characterized across a variety of cell types, a mechanistic understanding for how individual lipid classes contribute to mitochondrial structure and function remains nebulous. In this review, we address the biophysical properties of mitochondrial lipids and their related functional roles. We highlight the intrinsic curvature of the bulk mitochondrial phospholipid pool, with an emphasis on the nuances surrounding the mitochondrially-synthesized cardiolipin. We also outline emerging questions about other lipid classes - ether lipids, and sterols - with potential roles in mitochondrial physiology. We propose that further investigation is warranted to elucidate the specific properties of these lipids and their influence on mitochondrial architecture and function.
线粒体膜的功能多样、几何形状复杂、脂类组成独特。在线粒体的内膜中，高度弯曲的膜折叠结构称为嵴，这里是电子传递链的所在地，也是细胞产生能量的主要场所。相比之下，外膜是平坦的，但对于起始和介导与线粒体生理学相关的过程至关重要：自噬、细胞器间的接触、分裂和融合动力学以及代谢物的运输。尽管各种细胞类型中线粒体膜的脂类组成已经被描述，但对于单个脂类如何影响线粒体的结构和功能的机制理解仍然模糊不清。在这篇综述中，我们探讨了线粒体脂类的生物物理特性及其相关的功能作用。我们强调了大块线粒体磷脂池的固有曲率，并重点讨论了与线粒体合成的心磷脂相关的细微差别。我们还概述了关于其他脂类（醚脂和甾醇）在线粒体生理学中潜在作用的新兴问题。我们提出，有必要进行进一步的研究来阐明这些脂类的具体特性及其对线粒体结构和功能的影响。
