3fm7

From Proteopedia

Quaternary Structure of Drosophila melanogaster IC/Tctex-1/LC8; Allosteric Interactions of Dynein Light Chains with Dynein Intermediate Chain

Structural highlights

3fm7 is a 6 chain structure with sequence from Drosophila melanogaster. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3.5Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

DYLT_DROME Acts as one of several non-catalytic accessory components of the cytoplasmic dynein complex that are thought to be involved in linking dynein to cargos and to adapter proteins that regulate dynein function. Cytoplasmic dynein acts as a motor for the intracellular retrograde motility of vesicles and organelles along microtubules. Required for spermatid differentiation. Is not required for polarized transport in rhabdomere development and appears to be a non-essential component of the cytoplasmic dynein complex.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Dynein light chains are thought to increase binding efficiency of dynein intermediate chain to both dynein heavy chain and dynactin, but their exact role is not clear. Isothermal titration calorimetry and x-ray crystallography reported herein indicate that multivalency effects underlie efficient dynein assembly and regulation. For a ternary complex of a 60-amino acid segment of dynein intermediate chain (IC) bound to two homodimeric dynein light chains Tctex1 and LC8, there is a 50-fold affinity enhancement for the second light chain binding. For a designed IC construct containing two LC8 sites, observed the 1000-fold enhancement reflects a remarkably pure entropic chelate effect of a magnitude commensurate with theoretical predictions. The lower enhancement in wild-type IC is attributed to unfavorable free energy changes associated with incremental interactions of IC with Tctex1. Our results show assembled dynein IC as an elongated, flexible polybivalent duplex, and suggest that polybivalency is an important general mechanism for constructing stable yet reversible and functionally versatile complexes.

Multivalency in the assembly of intrinsically disordered Dynein intermediate chain.,Hall J, Karplus PA, Barbar E J Biol Chem. 2009 Nov 27;284(48):33115-21. Epub 2009 Sep 16. PMID:19759397^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Hall J, Karplus PA, Barbar E. Multivalency in the assembly of intrinsically disordered Dynein intermediate chain. J Biol Chem. 2009 Nov 27;284(48):33115-21. Epub 2009 Sep 16. PMID:19759397 doi:10.1074/jbc.M109.048587