The reversible interactions between LDs and mitochondria are tracked in real-time using a robust LDs-specific fluorescent probe (LDs-Tags). LDs exhibit active transport and are inclined to repeatedly search for a suitable contact site on the mitochondrial membrane under nutrient starvation. Intermittent larger jumps are observed between clustered small steps during this process.
Abstract:
Dynamic membrane contacts between lipid droplets (LDs) and mitochondria play key roles in lipid metabolism and energy homeostasis. Understanding the dynamics of LDs under energy stimulation is thereby crucial to disclosing the metabolic mechanism. Here, the reversible interactions between LDs and mitochondria are tracked in real-time using a robust LDs-specific fluorescent probe (LDs-Tags). Through tracking the dynamics of LDs at the single-particle level, spatiotemporal heterogeneity is revealed. LDs in starved cells communicate and integrate their activities (i.e., lipid exchange) through a membrane contact site-mediated mechanism. Thus the diffusion is intermittently alternated between active and confined states. Statistical analysis shows that the translocation of LDs in response to starvation stress is non-Gaussian, and obeys nonergodic-like behavior. These results provide deep understanding of the anomalous diffusion of LDs in living cells, and also afford guidance for rationally designing efficient transporter.
Author list:
Zhongju Ye, Chengyuan Hu, Junli Wang, Hua Liu, Luping Li, Jie Yuan, Ji Won Ha, Zhaohui Li*, Lehui Xiao*
How to cite:
Z. Ye, C. Hu, J. Wang, H. Liu, L. Li, J. Yuan, J. Won Ha, Z. Li, L. Xiao, Exploration 2023, 20230002.
https://doi.org/10.1002/EXP.20230002