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Rogers, S. L.

Publications and source records attributed to Rogers, S. L..

2 recordsLinked to original sources

CryoET shows cofilactin filaments inside the microtubule lumen

Cytoplasmic microtubules are tubular polymers that can harbor small proteins or filaments inside their lumen. The identity of these objects and what causes their accumulation has not been conclusively established. Here, we used cryogenic electron tomography (cryoET) of Drosophila S2 cell protrusions and found filaments inside the microtubule lumen, which resemble those reported recently in human HAP1 cells. The frequency of these filaments increased upon inhibition of the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) with the small-molecule drug thapsigargin. Subtomogram averaging showed that the luminal filaments adopt a helical structure reminiscent of cofilin-bound actin (cofilactin). Consistent with this, cofilin was activated in cells under the same conditions that increased luminal filament occurrence. Furthermore, RNAi knock-down of cofilin reduced the frequency of luminal filaments with cofilactin morphology. These results suggest that cofilin activation stimulates its accumulation on actin filaments inside the microtubule lumen.

cell biology↗

Microtubule acetylation is required for mechanosensation in Drosophila

At the cellular level, -tubulin acetylation alters the structure of microtubules to render them mechanically resistant to compressive forces. How this biochemical property of microtubule acetylation relates to mechanosensation remains unknown, though prior studies have shown that microtubule acetylation plays a role in touch perception. Here, we identify the major Drosophila -tubulin acetylase (dTAT) and show that it plays key roles in several forms of mechanosensation while exerting little effect on other sensory modalities. dTAT is highly expressed in neurons of the larval peripheral nervous system (PNS), but is not required for normal neuronal morphogenesis. We show that mutation of the acetylase gene or the K40 acetylation site in -tubulin impairs mechanical sensitivity in sensory neurons and behavioral responses to gentle touch, harsh touch, gravity, and sound stimulus, but not thermal stimulus. Finally, we show that dTAT is required for mechanically-induced activation of NOMPC, a microtubule-associated transient receptor potential channel, and functions to maintain integrity of the microtubule cytoskeleton in response to mechanical stimulation.

cell biology↗