VAMPs sensitive to tetanus toxin are required for cortical granule exocytosis in mouse oocytes

Journal Article · Sun Aug 15 04:00:00 EDT 2021 · Experimental Cell Research

DOI:https://doi.org/10.1016/J.YEXCR.2021.112629· OSTI ID:23195589

Paola, Matilde de ^[1]; Garrido, Facundo; Zanetti, María N. ^[1]

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1. Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza (Argentina)

Highlights: • Cortical granule exocytosis is sensitive to tetanus toxin in mouse oocytes. • VAMP1 and VAMP3 proteins participate in cortical granule exocytosis. • This work confirms that cortical granule exocytosis is mediated by SNARE complex. Fusion of cortical granules with oocyte plasma membrane is one of the most significant secretory events to prevent polyspermy during oocyte activation. Cortical granule exocytosis (CGE) is distinct from most other exocytosis because cortical granules are not renewed after secretion. However, it is thought to be mediated by SNARE complex, which mediates membrane fusion in other exocytoses. SNAREs proteins are divided into Q (glutamine)- and R (arginine)-SNAREs. Q-SNAREs include Syntaxins and SNAP25 family, and R-SNAREs include VAMPs family. In mouse oocytes, Syntaxin4 and SNAP23 have been involved in CGE; nevertheless, it is unknown if VAMP is required. Here, we demonstrated by RT-PCR and immunoblotting that VAMP1 and VAMP3 are expressed in mouse oocyte, and they localized in the cortical region of this cell. Using a functional assay to quantify CGE, we showed that tetanus toxin –which specifically cleavages VAMP1, VAMP2 or VAMP3– inhibited CGE suggesting that at least one VAMP was necessary. Function blocking assays demonstrated that only the microinjection of anti-VAMP1 or anti-VAMP3 antibodies abolished CGE in activated oocytes. These findings demonstrate that R-SNAREs sensitive to tetanus toxin, VAMP1 and VAMP3 –but not VAMP2-, are required for CGE and demonstrate that CGE is mediated by the SNARE complex.

• OSTI ID: 23195589
• Journal Information: Experimental Cell Research, Journal Name: Experimental Cell Research Journal Issue: 1 Vol. 405; ISSN 0014-4827; ISSN ECREAL
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
ANTIBODIES
ARGININE
GLUTAMINE
MICE
OOCYTES
POLYMERASE CHAIN REACTION
PROTEINS
SECRETION
TETANUS
TOXINS