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

Abstract

We describe the localization of the golgin GMAP210 and the intraflagellar protein IFT88 in the Golgi of spermatids and the participation of these two proteins in the development of the acrosome-acroplaxome complex, the head-tail coupling apparatus (HTCA) and the spermatid tail. Immunocytochemical experiments show that GMAP210 predominates in the cis-Golgi whereas IFT88 prevails in the trans-Golgi network. Both proteins co-localize in proacrosomal vesicles, along acrosome membranes, the HTCA and the developing tail. IFT88 persists in the acrosome-acroplaxome region of the sperm head whereas GMAP210 is not longer seen there. Spermatids of the Ift88 mouse mutant display abnormal head shaping and are tail-less. GMAP210 is visualized in the Ift88 mutant during acrosome-acroplaxome biogenesis. However, GMAP210–stained vesicles, mitochondria and outer dense fiber material build up in the manchette region and fail to reach the abortive tail stump in the mutant. In vitro disruption of the spermatid Golgi and microtubules with Brefeldin-A and nocodazole blocks the progression of GMAP210- and IFT88-stained proacrosomal vesicles to the acrosome-acroplaxome complex but F-actin distribution in the acroplaxome is not affected. We provide the first evidence that IFT88 is present in the Golgi of spermatids, that the microtubule-associated golgin GMAP210 and IFT88 participate in acrosome, HTCA and tail biogenesis, and that defective intramanchette transport of cargos disrupts spermatid tail development.

SPEF2 functions in microtubule-mediated transport in elongating spermatids to ensure proper male germ cell differentiation

“…In wild-type mice, vesicles positive for the IFT88-interacting protein GMAP210 (TRIP11) were seen first in cis-Golgi, and then they sequentially colocalized with IFT88 in proacrosomal vesicles, acrosome membranes, the head-tail coupling apparatus and developing tail. However, in Ift88 mutant mice, Golgi-derived GMAP210-positive vesicles did not reach the tail region, suggesting defective IMT (Kierszenbaum et al, 2011b).…”

“…Indeed, Ift88 mutant mice share similar defects with Kif3a knockout mice (Kierszenbaum et al, 2011b). In wild-type mice, vesicles positive for the IFT88-interacting protein GMAP210 (TRIP11) were seen first in cis-Golgi, and then they sequentially colocalized with IFT88 in proacrosomal vesicles, acrosome membranes, the head-tail coupling apparatus and developing tail.…”

Cytoskeletal track selection during cargo transport in spermatids is relevant to male fertility

“…It also provides a temporary niche for proteins in transit to the manchette, and places proteins close to a spermatid nuclear region where condensation and transcriptional silencing start. As the biogenesis of the acrosome-acroplaxome-manchette complex is in progress, microtubules and associated proteins with functional requirements in spermiogenesis-including keratin 5/Sak57, 3 GMAP210, 8 IFT88,8 Hook1, 9 Ran GTPase 10 and ODF2, 11 and components of the ubiquitin-proteasome system 12 -are transported to specific sites to transform a round spermatid into a self-propelling sperm.…”

“…15 More recently, it was shown that the golgin GMAP210 (for Golgi microtubule associated protein with a molecular mass of 210 kDa 16 ) resides in the cis-Golgi of spermatids and is involved in proacrosomal vesicle transport. 8 In somatic cells, GMAP210 is necessary for maintaining the integrity of the Golgi ribbon. 17,18 GMAP210 co-purifies with microtubules, 19,20 interacts with centrosomal γ-tubulin, 17 and when overexpressed perturbs the organization of the microtubule network.…”

“…8 The Ift88 mutant mouse is a convenient model for analyzing the role of the protein IFT88 during spermatid development because of a combined defect in IMT and IFT results in the production of tail-less spermatids. 8 The development of the acrosome-acroplaxome complex is not significantly disrupted in the Ift88 mutant.…”