Jaba Tkemaladze
Early embryonic development requires the transformation of a single cell into a complex, patterned organism. This process critically depends on the de novo formation of centrioles, which, unlike the canonical templated duplication in somatic cells, occurs without pre-existing organelles in oocytes and zygotes. This review synthesizes evidence from a systematic analysis of studies across model organisms to propose that de novo centriole biogenesis serves a dual, integrative function. It not only ensures the assembly of the mitotic apparatus but also acts as a fundamental organizing principle for the spatial assembly and asymmetric segregation of macromolecular complexes that induce cell differentiation. We delineate a stage-dependent model, from oogenic predetermination through the first cleavages, demonstrating how the nascent centriole acts as a scaffold for liquid-liquid phase separation (LLPS), co-condensing fate determinants like transcription factors, repressors, and localized mRNAs. Comparative and functional analyses from C. elegans to mice establish a causal link: disrupting centriole assembly or its association with determinants leads to defective asymmetric division and cell fate transformation. We conclude that de novo centriologenesis is the architectonic event that couples cell division with lineage specification, a deeply conserved mechanism whose disruption underpins severe human developmental disorders. The presented integrative model reframes the centrosome as an active conductor of embryonic patterning.