Oxford University Press, Biology of Reproduction, 1(88), 2013
DOI: 10.1095/biolreprod.112.103887
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The antral compartment in the ovary consists of two populations of oocytes that differ by their ability to resume meiosis and to develop to the blastocyst stage. Still for reasons not entirely clear, antral oocytes termed surrounded nucleolus (SN; 70% of the population of antral oocytes) develop to the blastocyst stage, while those called not-surrounded nucleolus (NSN) arrest at two cells. We profiled transcriptomic, proteomic and morphological characteristics of antral oocytes and observed that NSN oocyte arrest is associated with lack of cytoplasmic lattices coincident with reduced expression of MATER and ribosomal proteins. Cytoplasmic lattices have been shown to store maternally-derived mRNA and ribosomes in mammalian oocytes and embryos while MATER has been shown to be required for cytoplasmic lattices formation. Thus, we isolated antral oocytes from a Mater(tm/tm) mouse and we observed that 84% of oocytes are of the NSN type. Our results provide the first molecular evidence to account for inability of NSN-derived embryos to progress beyond the two-cell stage; these results may be relevant to naturally-occurring pre-implantation embryo demise in mammals.