National Institutes of Health/National Cancer Institute (NIH/NCI)
P01 CA240685
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
P20 GM113131-07S1
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01 GM129338
米国
National Science Foundation (NSF, United States)
2321501
米国
引用
ジャーナル: bioRxiv / 年: 2025 タイトル: Breaking Barriers: Transitioning from X-ray Crystallography to Cryo-EM for Structural Studies of ATAD2B. 著者: Hassan Zafar / Kiera L Malone / Ajit K Singh / Michael A Cianfrocco / Karen C Glass / 要旨: Cryo-electron microscopy (cryo-EM) has transformed structural biology by enabling near-atomic resolution of large macromolecular complexes without the need for crystallization. Here, we describe our ...Cryo-electron microscopy (cryo-EM) has transformed structural biology by enabling near-atomic resolution of large macromolecular complexes without the need for crystallization. Here, we describe our laboratory's transition from X-ray crystallography to single-particle cryo-EM to investigate the ATPase family AAA+ domain-containing protein 2B (ATAD2B), a chromatin regulator implicated in epigenetic signaling. We outline the challenges encountered during protein expression, purification, and sample preparation, including co-purification of the chaperonin GroEL, and strategies employed to overcome these obstacles. Our workflow highlights critical steps in sample optimization, grid vitrification, and data processing using CryoSPARC, cisTEM, and Topaz, as well as computational requirements for high-resolution reconstructions. We also discuss model building, refinement, and validation approaches, emphasizing best practices for new cryo-EM users. This work provides practical insights for structural biologists adopting cryo-EM, particularly for large, flexible protein complexes, and underscores the importance of integrated approaches combining biochemical, computational, and imaging strategies.