Unraveling novel molecular players regulating cristae membrane dynamics using live-cell STED super-resolution nanoscopy

• Applicant: Dr. Arun Kumar Kondadi
• Subject Area: Biochemistry ; Cell Biology
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 576272724

Mitochondria are vital double membrane-enclosed organelles playing multidimensional roles including ATP conversion, inflammation, metabolism, calcium buffering and programmed cell death. Various diseases like neurodegeneration, diabetes, cardiomyopathies and cancer are associated with perturbed mitochondrial inner membrane (IM) remodeling. Hence, unraveling the fundamental molecular mechanisms regulating IM remodeling will advance our understanding of the progression of various pathologies. Only five years ago, using live-cell stimulated emission depletion (STED) super-resolution (SR) nanoscopy, we and others showed that cristae membranes (CMs) undergo dynamic remodelling within individual mitochondria. Additionally, we showed that the dynamic remodelling of CMs was dependent on the MICOS complex proteins present at the crista junctions (CJs). CJs are pore-like structures, around 25 nm in diameter, which spatially demarcate the IM into smooth inner boundary membrane (IBM) and CM, present as invaginations towards the mitochondrial matrix. Due to the recent discovery of CM dynamics, the molecular players regulating them are poorly understood. I propose to conduct a multi-arrayed screen to identify novel molecules regulating cristae membrane morphology and dynamics. Based on reliable bioinformatic criteria, we narrowed down the screen involving MICOS interactome to a set of 110 proteins which could regulate CM remodeling. Further, we have already established methods for large-scale generation of knockout mammalian cell lines. Thus, we are equipped to undertake a multi-arrayed study based on fluorescence STED SR nanoscopy. Following generation of knockout cell lines, the screening procedure will involve investigation of aberrant cristae morphology and CM dynamics. We aim to use automated image analysis methods to quantify the CM dynamics. Further, biological characterisation will be performed on selected hit/s obtained from the multi-arrayed screen to gain novel molecular insights regulating cristae membrane remodeling.

• DFG Programme: Research Grants