April 7 2023
We would like to inform you that the 93rd IRCMS seminar has been scheduled as below.
* This IRCMS seminar is open to everyone.
Date : April 12, 2023 (Wednesday)
Venue : Onsite & Online
IRCMS Lounge & Zoom
Meeting ID: 892 9203 0064
Time : 16:00-17:00
Speaker : Dr. Takuya Shiota
Title : Photo-crosslinking Approach Reveals Mechanisms of Protein Translocation at Work in Vivo
Protein function is critically dependent on their proper folding and localization to specific cellular compartments. In particular, the translocation of newly synthesized proteins that are translated by ribosomes existing in the aqueous part of the cell, across hydrophobic biological membranes requires the assistance of specialized translocators. Despite significant advances in structural biology, the molecular mechanisms underlying protein translocation remain poorly understood. We have an optimized photo-crosslinking approach that allows us to analyze the protein-protein interactions during membrane protein translocation in vivo with high spatial resolution. Specifically, we introduce a photo-reactive unnatural amino acid, BPA, site-specifically into membrane proteins and use direct UV irradiation to capture snapshots of protein-protein interactions as they occur in vivo. In this seminar, I will describe two examples of this approach, one involving the mitochondrial Translocator of Outer Membrane (TOM) complex and the other focusing on the bacterial Beta-barrel Assembly Machinery (BAM) complex.
1. Germany et al., Discovery of a conserved rule behind the assembly of β-barrel membrane proteins., bioRxiv, 2021
2. Araiso et al, Structure of the mitochondrial import gate reveals distinct preprotein paths. Nature, 575(7782): 395-401
3. Gunasinghe and Shiota et al., The WD40 protein BamB mediates coupling of BAM complexes into assembly precincts in the bacterial outer membrane. Cell Rep., 23(9):2782-2794, 2018
4. Shiota et al., Molecular architecture of the active mitochondrial protein gate. Science, 349(6255): 1544-1548, 2015
Flyer: (Click to enlarge)