The mechanical properties of the cytoplasm and nucleoplasm are crucial for the correct and robust functioning of a cell and play a key role in understanding how mechanical signals are transferred to the nucleus. Here, we demonstrate remarkable shape mimicry between the cellular and nuclear shape of oocytes, following the externally applied deformation without direct contact between the cell cortex and the nucleus. This effect arises from a surprisingly soft and fluid-like nucleoplasm that barely resists external strain, while the viscoelastic cytoplasm drives shape transmission.
View Article and Find Full Text PDFAnnu Rev Cell Dev Biol
August 2025
Maternal storage is a fundamental feature of female gametes and is essential for maintaining oocyte quality and preserving developmental competence. Embryonic development relies on maternally deposited proteins, transcripts, and nutrients, yet the mechanisms by which oocytes accumulate and store these critical factors-particularly proteins-remain poorly understood. Across eukaryotes, diverse protein storage strategies have evolved, reflecting both conserved and species-specific adaptations.
View Article and Find Full Text PDFMammalian oocytes are filled with poorly understood structures called cytoplasmic lattices. First discovered in the 1960s and speculated to correspond to mammalian yolk, ribosomal arrays, or intermediate filaments, their function has remained enigmatic to date. Here, we show that cytoplasmic lattices are sites where oocytes store essential proteins for early embryonic development.
View Article and Find Full Text PDFA new life begins with the unification of the maternal and paternal chromosomes upon fertilization. The parental chromosomes first become enclosed in two separate pronuclei near the surface of the fertilized egg. The mechanisms that then move the pronuclei inwards for their unification are only poorly understood in mammals.
View Article and Find Full Text PDFHereditary forms of Wilms arise from developmentally arrested clones of renal progenitor cells with biallelic mutations of WT1; recently, it has been found that Wilms tumors may also be associated with biallelic mutations in DICER1 or DROSHA, crucial for miRNA biogenesis. We have previously shown that a critical role for WT1 during normal nephrogenesis is to suppress transcription of the Polycomb group protein, EZH2, thereby de-repressing genes in the differentiation cascade. Here we show that WT1 also suppresses translation of EZH2.
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