|
||
J. Cell Biol.,
Volume 145, Number 1, April 5, 1999 83-98

* Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla Apdo. 1095, 41080-Sevilla, Spain; and We report that a peripheral Golgi protein
with a molecular mass of 210 kD localized at the cis-Golgi network (Rios, R.M., A.M. Tassin, C. Celati, C. Antony, M.C. Boissier, J.C. Homberg, and M. Bornens.
1994. J. Cell Biol. 125:997-1013) is a microtubule-binding protein that associates in situ with a subpopulation
of stable microtubules. Interaction of this protein, now
called GMAP-210, for Golgi microtubule-associated
protein 210, with microtubules in vitro is direct, tight
and nucleotide-independent. Biochemical analysis further suggests that GMAP-210 specifically binds to microtubule ends. The full-length cDNA encoding
GMAP-210 predicts a protein of 1,979 amino acids with
a very long central coiled-coil domain. Deletion analyses in vitro show that the COOH terminus of GMAP-210 binds to microtubules whereas the NH2 terminus
binds to Golgi membranes. Overexpression of GMAP-210-encoding cDNA induced a dramatic enlargement
of the Golgi apparatus and perturbations in the microtubule network. These effects did not occur when a mutant lacking the COOH-terminal domain was expressed. When transfected in fusion with the green
fluorescent protein, the NH2-terminal domain associated with the cis-Golgi network whereas the COOH-terminal microtubule-binding domain localized at the
centrosome. Altogether these data support the view
that GMAP-210 serves to link the cis-Golgi network to
the minus ends of centrosome-nucleated microtubules. In addition, this interaction appears essential for ensuring the proper morphology and size of the Golgi apparatus.
Institut
Curie, Section Recherche, UMR144 du CNRS, 75248 Paris, Cedex 05, France
This article has been cited by other articles:
|
|