PIOCHE-DURIEU, C. | Search bioRxiv

bioRxiv2026

Transcriptional coupling of metabolism and cell mechanics controls humanneuroepithelium morphogenesis

Tissue morphogenesis integrates developmental programs with cell mechanics, yet the mechanisms coupling these processes remain poorly understood. We investigated this link during neuroepithelial morphogenesis in human iPSC-derived dorsal spinal organoids. We found that PAX3, a transcription factor whose loss causes neural tube defects, promotes force-bearing adherens junction assembly. It does so by driving apical clustering of N-cadherin complexes, thereby enabling neuroepithelial morphogenesis, a function conserved in the mouse neural tube. Transcriptomic, metabolomic, and functional analyses show that PAX3 sustains upper glycolysis and the associated mannose-dependent glycosylation pathways. Exogenous mannose rescues cadherin clustering and adherens junction mechanics following PAX3 loss, whereas inhibition of glycolysis or glycosylation recapitulates these defects. These findings establish mannose metabolism as a PAX3-regulated pathway conferring mechanical competence to developing tissues.

developmental biology↗

bioRxiv2021

Evolutionary conservation of centriole rotational asymmetry in the human centrosome

Centrioles are formed by microtubule triplets in a nine-fold symmetric arrangement. In flagellated protists and in animal multiciliated cells, accessory structures tethered to specific triplets render the centrioles rotationally asymmetric, a property that is key to cytoskeletal and cellular organization in these contexts. In contrast, centrioles within the centrosome of animal cells display no conspicuous rotational asymmetry. Here, we uncover rotationally asymmetric molecular features in human centrioles. Using ultrastructure expansion microscopy, we show that LRRCC1, the ortholog of a protein originally characterized in flagellate green algae, associates preferentially to two consecutive triplets in the distal lumen of human centrioles. LRRCC1 partially co-localizes and affects the recruitment of another distal component, C2CD3, which also has an asymmetric localization pattern in the centriole lumen. Together, LRRCC1 and C2CD3 delineate a structure reminiscent of a filamentous density observed by electron microscopy in flagellates, termed the acorn. Functionally, the depletion of LRRCC1 in human cells induced defects in centriole structure, ciliary assembly and ciliary signaling, supporting that LRRCC1 cooperates with C2CD3 to organizing the distal region of centrioles. Since a mutation in the LRRCC1 gene has been identified in Joubert syndrome patients, this finding is relevant in the context of human ciliopathies. Taken together, our results demonstrate that rotational asymmetry is an ancient property of centrioles that is broadly conserved in human cells. Our work also reveals that asymmetrically localized proteins are key for primary ciliogenesis and ciliary signaling in human cells.

cell biology↗