MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, UK.
Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, UK.
Trends Cell Biol. 2017 Jun;27(6):393-402. doi: 10.1016/j.tcb.2017.02.006. Epub 2017 Mar 8.
Allometric scaling of metabolic rate results in lower total mitochondrial oxygen consumption with increasing organismal size. This is considered a universal law in biology. Here, we discuss how allometric laws impose size-dependent limits to mitochondrial activity at the cellular level. This cell-size-dependent mitochondrial metabolic activity results in nonlinear scaling of metabolism in proliferating cells, which can explain size homeostasis. The allometry in mitochondrial activity can be controlled through mitochondrial fusion and fission machinery, suggesting that mitochondrial connectivity can bypass transport limitations, the presumed biophysical basis for allometry. As physical size affects cellular functionality, cell-size-dependent metabolism becomes directly relevant for development, metabolic diseases, and aging.
代谢率的异速缩放导致随着生物体尺寸的增加，线粒体总耗氧量降低。这被认为是生物学中的普遍规律。在这里，我们讨论异速规律如何在细胞水平上对线粒体活性施加尺寸依赖性限制。这种细胞尺寸依赖性线粒体代谢活性导致增殖细胞代谢的非线性缩放，这可以解释大小的恒定性。线粒体活性的异速可以通过线粒体融合和裂变机制来控制，这表明线粒体的连通性可以绕过运输限制，这是异速的假定物理基础。由于物理尺寸会影响细胞功能，因此细胞尺寸依赖性代谢对于发育、代谢疾病和衰老变得直接相关。
