title: Developmental arrest and mouse antral not-surrounded nucleolus oocytes.
abstract: 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. For reasons still not entirely clear, antral oocytes termed surrounded nucleolus (SN; 70% of the population of antral oocytes) develop to the blastocyst stage, whereas 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, and MATER has been shown to be required for cytoplasmic lattice 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 preimplantation embryo demise in mammals.
authors.affiliation: Scientific Department, Research Center for Regenerative Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. m.monti@smatteo.pv.it
authors.forename: Manuela
authors.initials: M
authors.lastname: Monti
authors.forename: Mario
authors.initials: M
authors.lastname: Zanoni
authors.forename: Alberto
authors.initials: A
authors.lastname: Calligaro
authors.forename: Minoru S H
authors.initials: MS
authors.lastname: Ko
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Mauri
authors.forename: Carlo Alberto
authors.initials: CA
authors.lastname: Redi
mesh_terms: D000818:Animals; D000941:Antigens / Q000235:genetics / Q000378:metabolism; D001755:Blastocyst / Q000166:cytology / Q000502:physiology; D002455:Cell Division; D004527:Egg Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D008055:Lipids / Q000737:chemistry; D051379:Mice; D018345:Mice, Knockout; D020411:Oligonucleotide Array Sequence Analysis; D009865:Oocytes / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D000941:Antigens; D004527:Egg Proteins; D008055:Lipids; C416503:Nalp5 protein, mouse