6H4L

Structure of Titin M4 trigonal form

Summary for 6H4L

• Entry DOI: 10.2210/pdb6h4l/pdb
• Related: 3QP3
• Descriptor: Titin, ZINC ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: titin, muscle, sarcomere, ig-like, structural protein
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 1
• Total formula weight: 11721.57

Authors

Sauer, F.,Wilmanns, M. (deposition date: 2018-07-21, release date: 2019-08-07, Last modification date: 2020-02-19)

Primary citation

Chatziefthimiou, S.D.,Hornburg, P.,Sauer, F.,Mueller, S.,Ugurlar, D.,Xu, E.R.,Wilmanns, M.
Structural diversity in the atomic resolution 3D fingerprint of the titin M-band segment.
Plos One, 14:e0226693-e0226693, 2019

PubMed Abstract: In striated muscles, molecular filaments are largely composed of long protein chains with extensive arrays of identically folded domains, referred to as "beads-on-a-string". It remains a largely unresolved question how these domains have developed a unique molecular profile such that each carries out a distinct function without false-positive readout. This study focuses on the M-band segment of the sarcomeric protein titin, which comprises ten identically folded immunoglobulin domains. Comparative analysis of high-resolution structures of six of these domains ‒ M1, M3, M4, M5, M7, and M10 ‒ reveals considerable structural diversity within three distinct loops and a non-conserved pattern of exposed cysteines. Our data allow to structurally interpreting distinct pathological readouts that result from titinopathy-associated variants. Our findings support general principles that could be used to identify individual structural/functional profiles of hundreds of identically folded protein domains within the sarcomere and other densely crowded cellular environments.

PubMed: 31856237
DOI: 10.1371/journal.pone.0226693

Experimental method

X-RAY DIFFRACTION (1.6 Å)