6M5G

F-actin-Utrophin complex

Summary for 6M5G

• Entry DOI: 10.2210/pdb6m5g/pdb
• EMDB information: 30085
• Descriptor: Actin, alpha skeletal muscle, Utrophin, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: utrophin, n-terminus actin binding domain, calponin homology, f-actin, f-actin marker protein, contractile protein
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 8
• Total formula weight: 305058.14

Authors

Kumari, A.,Ragunath, V.K.,Sirajuddin, M. (deposition date: 2020-03-10, release date: 2020-05-20, Last modification date: 2024-03-27)

Primary citation

Kumari, A.,Kesarwani, S.,Javoor, M.G.,Vinothkumar, K.R.,Sirajuddin, M.
Structural insights into actin filament recognition by commonly used cellular actin markers.
Embo J., 39:e104006-e104006, 2020

PubMed Abstract: Cellular studies of filamentous actin (F-actin) processes commonly utilize fluorescent versions of toxins, peptides, and proteins that bind actin. While the choice of these markers has been largely based on availability and ease, there is a severe dearth of structural data for an informed judgment in employing suitable F-actin markers for a particular requirement. Here, we describe the electron cryomicroscopy structures of phalloidin, lifeAct, and utrophin bound to F-actin, providing a comprehensive high-resolution structural comparison of widely used actin markers and their influence towards F-actin. Our results show that phalloidin binding does not induce specific conformational change and lifeAct specifically recognizes closed D-loop conformation, i.e., ADP-Pi or ADP states of F-actin. The structural models aided designing of minimal utrophin and a shorter lifeAct, which can be utilized as F-actin marker. Together, our study provides a structural perspective, where the binding sites of utrophin and lifeAct overlap with majority of actin-binding proteins and thus offering an invaluable resource for researchers in choosing appropriate actin markers and generating new marker variants.

PubMed: 32567727
DOI: 10.15252/embj.2019104006

Experimental method

ELECTRON MICROSCOPY (3.6 Å)