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Rao, V. G.

Publications and source records attributed to Rao, V. G..

2 recordsLinked to original sources

Multiciliated cells adapt the mechanochemical Piezo1-Erk1/2-Yap1 cell proliferation axis to fine-tune centriole number.

Multiciliated cells (MCCs) are specialized epithelial cells that undergo massive amplification of centrioles, constructing several motile cilia to propel fluid flow. The abundance of cilia is critical for efficient fluid flow, yet how MCCs regulate centriole/cilia numbers remains a major knowledge gap. We have shown that mechanical tension plays a central role in regulating apical area and centriole number in MCCs. Here, we demonstrate that centriole amplification is controlled by a mechanochemical pathway essential for cell proliferation in cycling cells. Specifically, MCCs under tension use Piezo1-mediated calcium signaling to drive Erk[1/2] phosphorylation via PKC and subsequent Yap1 activation. Remarkably, MCCs use this pathway to activate a cilia-specific transcription program, influencing the expression of Foxj1, a master regulator of motile ciliogenesis. Our work is the first to identify a novel function for an important mechanochemical pathway in centriole amplification in MCCs, offering new insights into ciliopathies and cancer, where aberrant centriole numbers are implicated. TeaserThis study demonstrates that multiciliated cells utilize the mechanochemical Piezo1-Erk1/2-Yap1 cell proliferation axis to activate the cilia-specific transcriptional factor Foxj1 and amplify centrioles in a tension- dependent manner.

cell biology↗

Mechanisms of cilia regeneration in Xenopus multiciliated epithelium in vivo.

Cilia regeneration is a physiological event, and while studied extensively in unicellular organisms, it remains poorly understood in vertebrates. In this study, using Xenopus multiciliated cells (MCCs) as a model, we demonstrate that, unlike unicellular organisms, deciliation removes the transition zone (TZ) and the ciliary axoneme. While MCCs immediately begin the regeneration of the ciliary axoneme, surprisingly, the assembly of TZ is delayed. However, ciliary tip proteins, Sentan and Clamp, localize to regenerating cilia without delay. Using cycloheximide (CHX) to block new protein synthesis, we show that the TZ protein B9d1 is not a component of the cilia precursor pool and requires new transcription/translation, providing insights into the delayed repair of TZ. Moreover, MCCs in CHX treatment assemble fewer ([~] 10 vs. [~]150 in controls) but near wild-type length (ranging between 60 to 90%) cilia by gradually concentrating ciliogenesis proteins like IFTs at a select few basal bodies. Using mathematical modeling, we show that cilia length compared to cilia number influences the force generated by MCCs more. In summary, our results question the requirement of TZ in motile cilia assembly and provide insights into how cells determine organelle size and number.

cell biology↗