New insights into oocyte cytoplasmic lattice-associated proteins

The cytoplasmic lattices (CPLs) are fibrous structures of the mammalian oocyte cytoplasm that are needed to store ribosomes and maternal proteins in insoluble form to prevent their degradation, activation, and nuclear transfer.UHRF1 and the members of the subcortical maternal complex colocalize with the CPLs, and their deficiency results in lattice impairment.Mutations in the maternal effect genes Nlrp14 and Padi6 cause maturation defects and CPL deficiency in mouse oocytes, leading to lack of the CPL storage function and impaired cytoplasmic UHRF1 abundance, abnormal nuclear localization of DNMT1, and failure of epigenetic reprogramming, as well as defective zygotic genome activation and embryo development beyond the two-cell stage.Mouse mutants of CPL-associated proteins do not mimic human imprinting defects, suggesting species-specific differences. Oocyte maturation and preimplantation embryo development are critical to successful pregnancy outcomes and the correct establishment and maintenance of genomic imprinting. Thanks to novel technologies and omics studies in human patients and mouse models, the importance of the proteins associated with the cytoplasmic lattices (CPLs), highly abundant structures found in the cytoplasm of mammalian oocytes and preimplantation embryos, in the maternal to zygotic transition is becoming increasingly evident. This review highlights the recent discoveries on the role of these proteins in protein storage and other oocyte cytoplasmic processes, epigenetic reprogramming, and zygotic genome activation (ZGA). A better comprehension of these events may significantly improve clinical diagnosis and pave the way for targeted interventions aiming to correct or mitigate female fertility issues and genomic imprinting disorders. Oocyte maturation and preimplantation embryo development are critical to successful pregnancy outcomes and the correct establishment and maintenance of genomic imprinting. Thanks to novel technologies and omics studies in human patients and mouse models, the importance of the proteins associated with the cytoplasmic lattices (CPLs), highly abundant structures found in the cytoplasm of mammalian oocytes and preimplantation embryos, in the maternal to zygotic transition is becoming increasingly evident. This review highlights the recent discoveries on the role of these proteins in protein storage and other oocyte cytoplasmic processes, epigenetic reprogramming, and zygotic genome activation (ZGA). A better c