Resumen de Inmunolocalización mediante microscopía confocal de la proteína disulfuro isomerasa a1 (PDIA 1) en ovocitos y zigotos porcinos
Raquel Romar Andrés, M. D. Saavedra-Guerrero, María Pilar Coy Fuster, M. Avilés
Protein disulfide isomerase (PDI) protein compresses a numerous family of proteins residing at the endoplasmic reticulum where they catalyze disulfide bond formation, breakage, and rearrangement in all nonnative protein and peptide substrates. They are also involved in a wide range of other biological functions, although it is unclear for many of these reactions how they escape the ER. It has been indicated that PDI is also a marker for the release of intracellular contents. In oocytes, disulfide bond formation is in part responsible of the zona pellucida hardening and thus of preventing polyspermy. In case PDI were released from oocytes at fertilization time they might have a role in gamete interaction so, we studied PDIA1 distribution in pig oocytes and zygotes. After in vitro maturation and fertilization, oocytes and zygotes were fixed, permeabilized and stained with a primary anti-PDIA1 antibody followed by a secondary antibody. Visualization of oocytes under confocal microscopy revealed that PDIA1 protein is located at the periphery, under oolema level, with a uniform punctuate pattern. At cortex level aggregates of protein were also observed. Interestingly the protein staining disappeared in zygotes suggesting that PDIA1 is released at fertilization time. Its likely role in fertilization needs further study.
