IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
alpha SNAP is involved in cortical granules exocytosis and polarity in mouse oocytes
Autor/es:
DE PAOLA, MARIA MATILDE; RINALDINI, ESTEFANÍAC; CAPPA, ANDREA ISABEL; MAYORGA, LUIS SEGUNDO; BATIZ, LUIS FEDERICO; MICHAUT, MARCELA ALEJANDRA
Lugar:
Puerto Natales, Chile
Reunión:
Workshop; EMBO Workshop: Current advances in membrane trafficking: Implications for polarity and diseases; 2014
Institución organizadora:
EMBO. European Molecular Biology Organization
Resumen:
α-SNAP is involved in Cortical Granules exocytosis and polarity in mouse oocytes. de Paola M.M.1, Rinaldini E.2, Cappa, A.1, Mayorga, L.1, Bátiz, F.2,Michaut, M.1,2. 1IHEM-CONICET-Mendoza, Argentina, 2 ICB, UNCuyo, Mendoza, Argentina; 3IAHP, UACh, Valdivia, Chile SNAPs play a key role in different aspects of cell biology such as membrane fusion events, including vesicular traffic and exocytosis, and many others like cell polarity, cell division and apoptosis. SNAPs act as adaptor proteins that physically link SNAREs to NSF, thereby mediating disassembly and recycling of SNARE complexes. It has been shown that SNAP/NSF complex is essential for ER to Golgi transport, homotypic endosome fusion, TGN to basolateral and apical membranes transport, proteins transport in polarized cells, synaptic vesicle fusion in neurons and many other exocytosis such as lung surfactant, secretory granule fusion in chromaffin cells, insulin secretion in islets of Langerhans and sperm acrosome reaction. In female mammals, cortical granules exocytosis (CGE) is the primary mechanism in preventing polyspermic fertilization. We demonstrated for the first time the presence of SNAP/NSF complex in mammalian oocytes, using RT-PCR, WB and IFI techniques in mice model. Furthermore, this complex is necessary for CGE since microinjection of specific antibodies inhibit this process. Hydrocephalus with hop gait (hyh) is a recessive inheritable mouse disease that arose spontaneously in C57BL/10J mouse strain. A missense mutation in the gene encoding for α-SNAP causes the substitution of a highly conserved methionine at amino acid residue 105 for isoleucine (M105I). Due to α-SNAP Knock Out mice is embryonically lethal in mice, the hyh mice provide a unique in vivo model for in-depth research of α-SNAP function in membrane fusion and trafficking events. We have determined that hyh female have a strongly reduced in vivo and in vitro fertility. Aditionally, some hyh oocytes show an abnormal CG polarity, suggesting that α-SNAP might have a function in CG migration. Altogether, our results strongly suggest that α-SNAP/NSF complex is involved in CGE process, CG distribution and/or cell polarity, and that SNAPs failure might leads to reduced female fertility.