In-cell structures of a conserved supramolecular array at the mitochondria-cytoskeleton interface in mammalian sperm

• DOI: 10.1101/2021.02.16.431372
• Publication Date: 2021-02-17T20:46:05Z
• Authors: Miguel Ricardo Leung; Riccardo Zenezini...; Marc C. Roelofs; Johannes F. Hevler; Ravi Teja Ravi; Paula Maitan; Min Zhang; Heiko Henning; Elizabeth G. Brom...; Stuart C. Howes; Bart M. Gadella; Albert J.R. Heck; Tzviya Zeev-Ben-M...
• Keywords: cryo27 FIB milling; 0301 basic medicine; mitochondria-cytoskeleton contact; 03 medical and health sciences; cross-linking mass spectrometry; subtomogram averaging; sperm; cryo-electron tomography

Summary Mitochondria-cytoskeleton interactions modulate cellular physiology by regulating mitochondrial transport, positioning, and immobilization. However, there is very little structural information defining mitochondria-cytoskeleton interfaces in any cell type. Here, we use cryo-focused ion beam milling-enabled cryo-electron tomography to image mammalian sperm, where mitochondria wrap around the ciliary cytoskeleton. We find that are tethered their neighbors through inter-mitochondrial linkers anchored cytoskeleton ordered arrays on outer membrane. subtomogram averaging resolve in-cell structures of these from three species, revealing they conserved across species despite variations dimensions cristae organization. consist boat-shaped particles a network membrane pores whose arrangement consistent with voltage dependent anion channels. Proteomics cross-linking mass spectrometry suggest composed glycerol kinase-like proteins. Ordered supramolecular assemblies may serve stabilize similar contact sites other types need be immobilized specific subcellular environments, such as muscles neurons.