GMAP-210 Recruits γ-Tubulin Complexes to cis-Golgi Membranes and Is Required for Golgi Ribbon Formation

Abstract

Mammalian cells concentrate Golgi membranes around the centrosome in a microtubule-dependent manner. The mechanisms involved in generating a single Golgi ribbon in the periphery of the centrosome remain unknown. Here we show that GMAP-210, a cis-Golgi microtubule binding protein, recruits gamma-tubulin-containing complexes to Golgi membranes even in conditions where microtubule polymerization is prevented and independently of Golgi apparatus localization within the cell. Under overexpression conditions, very short microtubules, or tubulin oligomers, are stabilized on Golgi membranes. GMAP-210 depletion by RNA interference results in extensive fragmentation of the Golgi apparatus, supporting a role for GMAP-210 in Golgi ribbon formation. Targeting of GMAP-210 or its C terminus to mitochondria induces the recruitment of gamma-tubulin to their surface and redistribution of mitochondria to a pericentrosomal location. All our experiments suggest that GMAP-210 displays microtubule anchoring and membrane fusion activities, thus contributing to the assembly and maintenance of the Golgi ribbon around the centrosome.

Selective Protection of an ARF1-GTP Signaling Axis by a Bacterial Scaffold Induces Bidirectional Trafficking Arrest

“…Through extensive analysis of published observations, we found two proteins that met these criteria: GMAP-210 and Golgin-160. GMAP-210 is a tubulin-binding protein that links small vesicles to organelle membranes via a curvature-sensing N-terminal ArfGAP1 Lipid Packing Sensor (ALPS) and a C-terminal GRIP-Related ARF Binding (GRAB) domain that interacts with ARF1-GTP (Drin et al, 2008; Ríos et al, 2004). Golgin-160, on the other hand, is found primarily on the cis -Golgi and is implicated in membrane transport by connecting ARF1-GTP vesicles to dynein motors (Yadav et al, 2012).…”

GMAP210 and IFT88 are present in the spermatid golgi apparatus and participate in the development of the acrosome–acroplaxome complex, head–tail coupling apparatus and tail

“…In epididymal sperm (rat and mouse), GMAP210 and IFT88 co-localize in the HTCA and tail. The presence of GMAP210 in the HTCA correlates with the ability of GMAP210 to interact with centrosomal γ-tubulin (Rios et al, 2004). Golgi membranes are largely confined to a region surrounding the centrosome or microtubule-organizing center and its aster of microtubules largely determines the positioning of the Golgi apparatus.…”

“…In the Ift88 mutant mouse, the development of the acrosome-acroplaxome complex appears undisturbed but a severe arrest in the transport of cargos along the microtubule-containing manchette results in the development of tail-less spermatids. Based on the GMAP210 knockdown phenotype, showing Golgi dispersal (Rios et al , 2004), experiments affecting Golgi positioning without disrupting secretion or the organization of the actin and microtubule networks (Yadav et al, 2009), and the Ift88 mutant spermatid phenotype (this work), we propose that GMAP210 contributes to spermatid Golgi-centrosome positioning, a condition required for normal acrosome biogenesis, and to the accurate delivery of cargos by intramanchette transport to the HTCA, involving microtubule-based IFT88 and the F-actin-myosin Va transport system. Our observations open new molecular perspectives to understand the role of GMAP210 and IFT88 in sperm development leading to the clinical characterization of pleiotropic or idiopathic causes of male infertility.…”

“…GMAP210 relocates to the medial compartment in the presence of Brefeldin-A (Rios et al, 1994), co-purifies with microtubules (Infante et al, 1999; Kim et al, 2007), and, when over-expressed, breaks down the Golgi into aggregates of small vesicles (Pernet-Gallay et al, 2002) and perturbs the organization of the microtubule network (Infante et al, 1999). GMAP210 is necessary for maintaining the integrity of the Golgi ribbon (Rios et al, 2004; Yadav et al, 2009). The C-terminal region of GMAP210 contains a GRAB domain (GRIP-related Arf binding domain, Gillingham et al, 2004) that specifically binds flat membranes in an Arf1-dependent manner in in vitro assays (Drin et al, 2008).…”

The significance of TRIP11 and T3 signaling pathway in renal cancer progression and survival of patients.

“…Coincidently with its different functions, TRIP11 can localise either to Golgi apparatus, acting as a golgin [5], or the nucleus, acting as coactivator of transcription. TRIP11 (also named TRIP230 and GMAP-210) was initially discovered as a protein interacting with retinoblastoma protein (Rb) and THR [6].…”