Unknown

Dataset Information

0

Dynactin, a conserved, ubiquitously expressed component of an activator of vesicle motility mediated by cytoplasmic dynein.


ABSTRACT: Although cytoplasmic dynein is known to attach to microtubules and translocate toward their minus ends, dynein's ability to serve in vitro as a minus end-directed transporter of membranous organelles depends on additional soluble factors. We show here that a approximately 20S polypeptide complex (referred to as Activator I; Schroer, T. A., and M.P. Sheetz. 1991a. J. Cell Biol. 115:1309-1318.) stimulates dynein-mediated vesicle transport. A major component of the activator complex is a doublet of 150-kD polypeptides for which we propose the name dynactin (for dynein activator). The 20S dynactin complex is required for in vitro vesicle motility since depletion of it with a mAb to dynactin eliminates vesicle movement. Cloning of a brain specific isoform of dynactin from chicken reveals a 1,053 amino acid polypeptide composed of two coiled-coil alpha-helical domains interrupted by a spacer. Both this structural motif and the underlying primary sequence are highly conserved in vertebrates with 85% sequence identity within a central 1,000-residue domain of the chicken and rat proteins. As abundant as dynein, dynactin is ubiquitously expressed and appears to be encoded by a single gene that yields at least three alternative isoforms. The probable homologue in Drosophila is the gene Glued, whose protein product shares 50% sequence identity with vertebrate dynactin and whose function is essential for viability of most (and perhaps all) cells in the organism.

SUBMITTER: Gill SR 

PROVIDER: S-EPMC2289205 | biostudies-other | 1991 Dec

REPOSITORIES: biostudies-other

altmetric image

Publications

Dynactin, a conserved, ubiquitously expressed component of an activator of vesicle motility mediated by cytoplasmic dynein.

Gill S R SR   Schroer T A TA   Szilak I I   Steuer E R ER   Sheetz M P MP   Cleveland D W DW  

The Journal of cell biology 19911201 6


Although cytoplasmic dynein is known to attach to microtubules and translocate toward their minus ends, dynein's ability to serve in vitro as a minus end-directed transporter of membranous organelles depends on additional soluble factors. We show here that a approximately 20S polypeptide complex (referred to as Activator I; Schroer, T. A., and M.P. Sheetz. 1991a. J. Cell Biol. 115:1309-1318.) stimulates dynein-mediated vesicle transport. A major component of the activator complex is a doublet of  ...[more]

Similar Datasets

| S-EPMC4224444 | biostudies-literature
| S-EPMC3583065 | biostudies-literature
| S-EPMC1891230 | biostudies-literature
| S-EPMC3000974 | biostudies-literature
| S-EPMC3234784 | biostudies-literature
| S-EPMC7212015 | biostudies-literature
| S-EPMC5519373 | biostudies-literature
| S-EPMC4888239 | biostudies-literature
| S-EPMC5626548 | biostudies-literature
| S-EPMC5000072 | biostudies-literature