FIG. 5.

CPLs and lipid droplet content are good candidate markers for oocyte developmental competence. A) Model of GV SN and NSN oocytes showing the abundance or absence of CPLs (pink lines) and ribosomes (dark blue dots) freely dispersed in the cytoplasm. A magnification of a portion of the subcortical maternal complex (SCMC) is schematically represented (dotted box) as a model showing the interactions between the components (red, MATER; yellow, FILIA; green, PADI6; blue, TLE6; black, OOEP) and their overexpression (filled shape) or underexpression (empty shape) in the antral SN and NSN oocytes. In this model, the functional SN maternal complex (due to MATER and FILIA overexpression) is compared to a nonfunctional NSN maternal complex characterized by MATER and FILIA underexpression. For this reason, the SCMC disassembly of NSN oocytes is probably due to the inability of all four proteins to bind to MATER. B) Number of lipid droplets content in SN and NSN oocytes after morphometric computerized image analysis performed with ImageJ software. Data is displayed as means ± SEM. *P < 0.05 versus SN oocytes (Student t-test). C, D) Semithin sections of SN and NSN oocytes stained with toluidine blue. Black arrows point to lipid droplets. Bars = 10 μm. C', D') Binary images from C and D after ImageJ thresholding segmentation for the evaluation of oocyte lipid droplet content.