Get1 stabilizes an open dimer conformation of get3 ATPase by binding two distinct interfaces.
Tail-anchored (TA) proteins are integral membrane proteins that possess a single transmembrane domain near their carboxy terminus. TA proteins play critical roles in many important cellular processes such as membrane trafficking, protein translocation, and apoptosis. The GET complex mediates posttranslational insertion of newly synthesized TA proteins to the endoplasmic reticulum membrane. The GET complex is composed of the homodimeric Get3 ATPase and its heterooligomeric receptor, Get1/2. During insertion, the Get3 dimer shuttles between open and closed conformational states, coupled with ATP hydrolysis and the binding/release of TA proteins. We report crystal structures of ADP-bound Get3 in complex with the cytoplasmic domain of Get1 (Get1CD) in open and semi-open conformations at 3.0- and 4.5-Å resolutions, respectively. Our structures and biochemical data suggest that Get1 uses two interfaces to stabilize the open dimer conformation of Get3. We propose that one interface is sufficient for binding of Get1 by Get3, while the second interface stabilizes the open dimer conformation of Get3.
Structural Biology Laboratory, Life Science Division, Synchrotron Radiation Research Organization and Institute of Molecular and Cellular Biosciences, the University of Tokyo, Tokyo 113‐0032, Japan.
Keiko
K
Kubota
Atsushi
A
Yamagata
Yusuke
Y
Sato
Sakurako
S
Goto-Ito
Shuya
S
Fukai
D033942:Adaptor Proteins, Vesicular Transport / Q000737:chemistry / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray / Q000379:methods; D004721:Endoplasmic Reticulum / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism; D020662:Guanine Nucleotide Exchange Factors / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011499:Protein Processing, Post-Translational / Q000502:physiology; D017434:Protein Structure, Tertiary; D021381:Protein Transport / Q000502:physiology; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
D033942:Adaptor Proteins, Vesicular Transport; C503510:GET1 protein, S cerevisiae; C515526:Get2 protein, S cerevisiae; D020662:Guanine Nucleotide Exchange Factors; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases; C529048:Get3 protein, S cerevisiae