1pwj
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1pwj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1pwj" /> '''Structure of the Monomeric 8-kDa Dynein Ligh...)
Next diff →
Revision as of 22:03, 20 November 2007
|
Structure of the Monomeric 8-kDa Dynein Light Chain and Mechanism of Domain Swapped Dimer Assembly
Overview
The 8-kDa light chain of dynein (DLC8) is ubiquitously expressed in, various cell types. Other than serving as a light chain of the dynein, complexes, this highly conserved protein has been shown to bind a larger, number of proteins with diverse biological functions. DLC8 forms a, homodimer via three-dimensional domain swapping of an internal beta-strand, (the beta2-strand) at neutral pH. The protein undergoes non-reversible, dimer-to-monomer dissociation when the pH value of the protein solution, decreases. The three-dimensional structure of the DLC8 monomer determined, by NMR spectroscopy at pH 3.0 showed that the protein is well folded. The, major conformational change accompanied by dimer dissociation is in the, beta2-strand of the protein, which undergoes transition from a beta-strand, to a nascent alpha-helix. The monomer form of DLC8 is not capable of, binding to target proteins. Insertion of two flexible amino acid residues, in the tight beta1/beta2-loop dramatically stabilized the monomer, conformation of the protein. NMR studies showed that the mutation altered, the conformation as well as the three-dimensional domain swapping-mediated, assembly of the DLC8 dimer. The mutant DLC8 was unable to bind to its, targets even at physiological pH. The three-dimensional structure of the, mutant protein in its monomeric form provides the structural basis of the, mutation-induced stabilization of the monomer conformation. Based on the, experimental data, we conclude that the formation of the beta2-strand, swapping-mediated dimer is mandatory for the structure and function of, DLC8. We further note that the DLC8 dimer represents a novel mode of, three-dimensional domain swapping.
About this Structure
1PWJ is a Single protein structure of sequence from Rattus norvegicus. Full crystallographic information is available from OCA.
Reference
Structure of the monomeric 8-kDa dynein light chain and mechanism of the domain-swapped dimer assembly., Wang W, Lo KW, Kan HM, Fan JS, Zhang M, J Biol Chem. 2003 Oct 17;278(42):41491-9. Epub 2003 Aug 6. PMID:12904292
Page seeded by OCA on Wed Nov 21 00:11:09 2007
