第1172回生物科学セミナー

オルガネラ由来リボソームのクライオ電顕単粒子解析

Alexey Amunts博士(Science for Life Laboratory, Department of Biochemistry and Biophysics,Stockholm University, Sweden)

2017年10月03日(Tue)    17:00-18:00  理学部3号館 303号室   

Mitochondria and chloroplasts have specialized ribosomes for protein synthesis that have diverged from their bacterial and cytoplasmic counterparts. Using the most recent advances in electron cryo-microscopy (cryo-EM), we have determined the structures of translating human mitoribosome, its assembly intermediates, as well as spinach chlororibosome at 3-3.5 Å resolution. It reveals a distinct mechanism for mt-tRNA translocation, a remodeled architecture of the exit tunnel in different organellar ribosomes, and experimental evidence for the parallel evolution of ribosomes from chloroplast and mitochondrion. From the structural information we also identified new mitoribosomal assembly factors, which may link mitoribosomal biogenesis to other synthesis pathways in mitochondria