2A38

Crystal structure of the N-Terminus of titin

Summary for 2A38

• Entry DOI: 10.2210/pdb2a38/pdb
• Descriptor: Titin, CADMIUM ION (3 entities in total)
• Functional Keywords: titin, z1z2, structural protein
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm : Q8WZ42
• Total number of polymer chains: 3
• Total formula weight: 62536.58

Authors

Marino, M.,Muhle-Goll, C.,Svergun, D.,Demirel, M.,Mayans, O. (deposition date: 2005-06-24, release date: 2006-06-24, Last modification date: 2023-10-25)

Primary citation

Marino, M.,Zou, P.,Svergun, D.,Garcia, P.,Edlich, C.,Simon, B.,Wilmanns, M.,Muhle-Goll, C.,Mayans, O.
The Ig doublet Z1Z2: a model system for the hybrid analysis of conformational dynamics in Ig tandems from titin
Structure, 14:1437-1447, 2006

PubMed Abstract: Titin is a gigantic elastic filament that determines sarcomere ultrastructure and stretch response in vertebrate muscle. It folds into numerous Ig and FnIII domains connected in tandem. Data on interdomain arrangements and dynamics are essential for understanding the function of this filament. Here, we report a mechanistic analysis of the conformational dynamics of two Ig domains from the N terminus of titin, Z1Z2, by using X-ray crystallography, SAXS, NMR relaxation data, and residual dipolar couplings in combination. Z1Z2 preferentially adopts semiextended conformations in solution, with close-hinge arrangements representing low-probability states. Although interdomain contacts are not observed, the linker appears to acquire moderate rigidity via small, local hydrophobic interactions. Thus, Z1Z2 constitutes an adaptable modular system with restricted dynamics. We speculate that its preexistent conformation contributes to the selective recruitment of the binding partner telethonin onto the repetitive surface of the filament. The structural interconversion of four Z1Z2 conformers is analyzed.

PubMed: 16962974
DOI: 10.1016/j.str.2006.07.009

Experimental method

X-RAY DIFFRACTION (2 Å)