RT Journal Article SR Electronic T1 Filopodia-like protrusions of adjacent somatic cells shape the developmental potential of oocytes JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e202301963 DO 10.26508/lsa.202301963 VO 6 IS 6 A1 Crozet, Flora A1 Letort, Gaëlle A1 Bulteau, Rose A1 Da Silva, Christelle A1 Eichmuller, Adrien A1 Tortorelli, Anna Francesca A1 Blévinal, Joséphine A1 Belle, Morgane A1 Dumont, Julien A1 Piolot, Tristan A1 Dauphin, Aurélien A1 Coulpier, Fanny A1 Chédotal, Alain A1 Maître, Jean-Léon A1 Verlhac, Marie-Hélène A1 Clarke, Hugh J A1 Terret, Marie-Emilie YR 2023 UL http://www.life-science-alliance.org/content/6/6/e202301963.abstract AB The oocyte must grow and mature before fertilization, thanks to a close dialogue with the somatic cells that surround it. Part of this communication is through filopodia-like protrusions, called transzonal projections (TZPs), sent by the somatic cells to the oocyte membrane. To investigate the contribution of TZPs to oocyte quality, we impaired their structure by generating a full knockout mouse of the TZP structural component myosin-X (MYO10). Using spinning disk and super-resolution microscopy combined with a machine-learning approach to phenotype oocyte morphology, we show that the lack of Myo10 decreases TZP density during oocyte growth. Reduction in TZPs does not prevent oocyte growth but impairs oocyte-matrix integrity. Importantly, we reveal by transcriptomic analysis that gene expression is altered in TZP-deprived oocytes and that oocyte maturation and subsequent early embryonic development are partially affected, effectively reducing mouse fertility. We propose that TZPs play a role in the structural integrity of the germline–somatic complex, which is essential for regulating gene expression in the oocyte and thus its developmental potential.