Crystal structure of dynein light chain TcTex-1

J Biol Chem. 2005 Jun 10;280(23):21981-6. doi: 10.1074/jbc.M414643200. Epub 2005 Feb 8.

Abstract

TcTex-1, one of three dynein light chains of the dynein motor complex, has been implicated in targeting and binding cargoes to cytoplasmic dynein for retrograde or apical transport. Interactions between TcTex-1 and a diverse set of proteins such as the dynein intermediate chain, Fyn, DOC2, FIP1, the poliovirus receptor, CD155, and the rhodopsin cytoplasmic tail have been reported; yet, despite the broad range of targets, a consensus binding sequence remains uncertain. Consequently, we have solved the crystal structure of the full-length Drosophila homolog of TcTex-1 to 1.7 A resolution using MAD phasing to gain insight into its function and target specificity. The structure is homodimeric with a domain swapping of beta-strand 2 and has a fold similar to the dynein light chain, LC8. Based on structural alignment, the TcTex-1 and LC8 sequences show no identity, although the root mean square deviation between secondary structural elements is less than 1.6 A. Moreover, the N terminus, which is equivalent to beta-strand 1 in LC8, is splayed out and binds to a crystallographic dimer as an anti-parallel beta-strand at the same position as the neuronal nitric-oxide synthase peptide in the LC8 complex. Similarity to LC8 and comparison to the LC8-neuronal nitricoxide synthase complex suggest that TcTex-1 binds its targets in a similar manner as LC8 and provides insight to the lack of strict sequence identity among the targets for TcTex-1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Carrier Proteins / chemistry*
  • Cloning, Molecular
  • Crystallography, X-Ray
  • Cytoplasm / metabolism
  • Dimerization
  • Drosophila
  • Drosophila Proteins / chemistry*
  • Dyneins
  • Expressed Sequence Tags
  • Ligands
  • Membrane Proteins / chemistry
  • Microtubule-Associated Proteins / chemistry*
  • Models, Molecular
  • Molecular Sequence Data
  • Nuclear Proteins / chemistry*
  • Protein Binding
  • Protein Conformation
  • Protein Structure, Quaternary
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Receptors, Virus / chemistry
  • Rhodopsin / chemistry
  • Sequence Homology, Amino Acid
  • t-Complex Genome Region

Substances

  • Carrier Proteins
  • Drosophila Proteins
  • Ligands
  • Membrane Proteins
  • Microtubule-Associated Proteins
  • Nuclear Proteins
  • Receptors, Virus
  • ctp protein, Drosophila
  • poliovirus receptor
  • Rhodopsin
  • Dyneins

Associated data

  • PDB/1YGT