近日，洛桑联邦理工学院
在这项工作中，该课题组发现线粒体经常经历一种可逆的生物物理不稳定性，称为“珠化”，从管状变为有规则间隔的念珠状形态。生理珠化过程形成了一个特征长度尺度和同时介导的类核分解，并以高精度建立了类核间距离。珠化的发生是由钙内流触发的，而板层嵴内陷的密度调节了珠化的发生率，并在恢复后保留了类核间距。线粒体钙内流或内膜嵴完整性的失调导致了异常的类核凝固。他们的研究结果确定珠化是控制类核分布和遗传的机制，并对其调控提供了见解。
据悉，线粒体含DNA类核的分布对线粒体功能和基因组遗传至关重要；然而，没有已知的机制可以解释类核分离或它们的规则定位。
附：英文原文
Title: Pearling drives mitochondrial DNA nucleoid distribution
Author: Juan C. Landoni, Matthew D. Lycas, Josefa Macuada, Willi Stepp, Roméo Jaccard, Christopher J. Obara, Andrew S. Moore, David Hoffman, Jennifer Lippincott-Schwartz, Wallace Marshall, Gabriel Sturm, Suliana Manley
Issue&Volume: 2026-04-02
Abstract: The distribution of mitochondrial DNA–containing nucleoids is essential for mitochondrial function and genome inheritance; however, no known mechanisms can explain nucleoid segregation or their regular positioning. In this work, we found that mitochondria frequently undergo a reversible biophysical instability termed “pearling,” transforming from a tubular into a regularly spaced beads morphology. Physiological pearling imposed a characteristic length scale and simultaneously mediated nucleoid disaggregation and established internucleoid distancing with high precision. Pearling onset was triggered by calcium influx, whereas the density of lamellar cristae invaginations modulated pearling prevalence and preserved nucleoid spacing following recovery. The dysregulation of mitochondrial calcium influx or inner membrane cristae integrity caused aberrant nucleoid clustering. Our results identify pearling as a mechanism governing nucleoid distribution and inheritance and offer insights into its regulation.
DOI: adu5646
Source: https://www.science.org/doi/10.1126/science.adu5646