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Devitt, C. C.

Publications and source records attributed to Devitt, C. C..

3 recordsLinked to original sources

New tools reveal PCP-dependent polarized mechanics in the cortex and cytoplasm of single cells during convergent extension

Understanding biomechanics of biological systems is crucial for unraveling complex processes like tissue morphogenesis. However, current methods for studying cellular mechanics in vivo are limited by the need for specialized equipment and often provide limited spatiotemporal resolution. Here we introduce two new techniques, Tension by Transverse Fluctuation (TFlux) and in vivo microrheology, that overcome these limitations. They both offer time-resolved, subcellular biomechanical analysis using only fluorescent reporters and widely available microscopes. Employing these two techniques, we have revealed a planar cell polarity (PCP)-dependent mechanical gradient both in the cell cortex and the cytoplasm of individual cells engaged in convergent extension. Importantly, the non-invasive nature of these methods holds great promise for its application for uncovering subcellular mechanical variations across a wide array of biological contexts. SummaryNon-invasive imaging-based techniques providing time-resolved biomechanical analysis at subcellular scales in developing vertebrate embryos.

developmental biology↗

PCP and Septins govern the polarized organization and mechanics of the actin cytoskeleton during convergent extension.

Actin is generally required for cell movement but must be brought under the control of distinct developmental systems to drive specific morphogenetic processes, such as convergent extension (CE)1. This evolutionarily conserved collective cell movement elongates the body axis of all vertebrates and is governed by the Planar Cell Polarity (PCP) signaling system 1,2. Here, we sought to understand the interplay of PCP and actin during Xenopus CE. Our data provide new insights into the organization and emergence of polarity in this network and reveal new roles for the actin organizing Septins 3, thereby shedding light on the mechanisms by which developmental signaling systems exploit the ubiquitous machinery of cells to drive morphogenesis.

developmental biology↗

A systematic, label-free method for identifying RNA-associated proteins in vivo provides insights into vertebrate ciliary beating

Cell-type specific RNA-associated proteins (RAPs) are essential for development and homeostasis in animals. Despite a massive recent effort to systematically identify RAPs, we currently have few comprehensive rosters of cell-type specific RAPs in vertebrate tissues. Here, we demonstrate the feasibility of determining the RNA-interacting proteome of a defined vertebrate embryonic tissue using DIF-FRAC, a systematic and universal (i.e., label-free) method. Application of DIF-FRAC to cultured tissue explants of Xenopus mucociliary epithelium identified dozens of known RAPs as expected, but also several novel RAPs, including proteins related to assembly of the mitotic spindle and regulation of ciliary beating. In particular, we show that the inner dynein arm tether Cfap44 is an RNA-associated protein that localizes not only to axonemes, but also to liquid-like organelles in the cytoplasm called DynAPs. This result led us to discover that DynAPs are generally enriched for RNA. Together, these data provide a useful resource for a deeper understanding of mucociliary epithelia and demonstrate that DIF-FRAC will be broadly applicable for systematic identification of RAPs from embryonic tissues.

developmental biology↗