Start Up Project - Structure and distribution of ribosomes at the inner mitochondrial membrane
Expression of the genes encoded in the mitochondrial genome requires dedicated transcription and translation machineries. We previously studied the mechanism of mitochondrial transcription with a combination of structural and functional approaches. Recently, the structure of the mitochondrial ribosome was reported, which revealed that it differs from its cytosolic or bacterial counterparts, likely due to its task of translating proteins embedded in the inner mitochondrial membrane (IMM). Mitoribosomes interact with the IMM, where they may be organized into clusters and polyribosomes. However, little is known about how the organization and localization of gene expression is related to its regulation and the biogenesis of respiratory complexes. We will study the spatial organization of the translation machinery within human mitochondria with the use of cryo-electron tomography (cryo-ET). This approach will reveal the orientations and distributions of particles at the IMM and allow us to reconstruct native molecular structures. This work promises fundamental insights into how gene expression is coordinated and regulated in mitochondria.