Dynactin

From Wikipedia, the free encyclopedia

Dynactin or Dynein activator complex is a multi-subunit protein found in eukaryotic cells that aids in bidirectional intracellular organelle transport by binding to dynein and Kinesin II and linking them to the organelles to be transported.[1][2]

Contents

[edit] Structure and mechanism of action

Dynactin consists of many subunits of which the p150Glued doublet (encoded by the DCTN1 gene) is the largest and has been found to be essential for function. [1] This structure of dynactin is highly conserved in vertebrates. There are three isoforms encoded by a single gene. [3]

Dynactin interacts with dynein directly by the binding of dynein intermediate chains with the p150Glued doublet. [4]

[edit] Functions

Dynactin is often essential for dynein activity [1] and can be thought of as a "dynein receptor"[4] that modulates binding of dynein to cell organelles which are to be transported along microtubules. [5] Dynactin is involved in various processes like chromosome alignment and spindle organization [5] in cell division,[6] maintaining nuclear position[7] in addition to transport of various organelles in the cytoplasm. Dynactin also links Kinesin II to organelles.

[edit] See also

[edit] References

  1. ^ a b c Trina A. Schroer, DYNACTIN; Annual Review of Cell and Developmental Biology, Vol. 20: 759-779 (Volume publication date November 2004), (doi:10.1146/annurev.cellbio.20.012103.094623)
  2. ^ Sean W. Deacon1, Anna S. Serpinskaya1, Patricia S. Vaughan2, Monica Lopez Fanarraga3, Isabelle Vernos3, Kevin T. Vaughan2 and Vladimir I. Gelfand; Dynactin is required for bidirectional organelle transport; The Journal of Cell Biology, Volume 160, Number 3, 297-301; doi:10.1083/jcb.200210066
  3. ^ SR Gill, TA Schroer, I Szilak, ER Steuer, MP Sheetz and DW Cleveland; Dynactin, a conserved, ubiquitously expressed component of an activator of vesicle motility mediated by cytoplasmic dynein; The Journal of Cell Biology, Vol 115, 1639-1650
  4. ^ a b KT Vaughan and RB Vallee; Cytoplasmic dynein binds dynactin through a direct interaction between the intermediate chains and p150Glued; The Journal of Cell Biology, Vol 131, 1507-1516
  5. ^ a b CJ Echeverri, BM Paschal, KT Vaughan and RB Vallee; Molecular characterization of the 50-kD subunit of dynactin reveals function for the complex in chromosome alignment and spindle organization during mitosis; The Journal of Cell Biology, Vol 132, 617-633
  6. ^ Sher Karki and Erika LF Holzbaur; Cytoplasmic dynein and dynactin in cell division and intracellular transport; Current Opinion in Cell Biology, Volume 11, Issue 1, 1 February 1999, Pages 45-53; doi:10.1016/S0955-0674(99)80006-4
  7. ^ Whited JL, Cassell A, Brouillette M, Garrity PA.; Dynactin is required to maintain nuclear position within postmitotic Drosophila photoreceptor neurons; Development. 2004 Oct;131(19):4677-86. Epub 2004 Aug 25; PMID: 15329347