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bioRxiv · 10.1101/2020.11.18.389106

Adherent cell remodeling on micropatterns is modulated by Piezo1 channels

Jetta, D.·Bahrani Fard, M. R.·Sachs, F.·Munechika, K.·Hua, S. Z.
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Abstract

Adherent cells utilize local environmental cues to make decisions on their growth and movement. We have previously shown that HEK293 cells grown on the fibronectin stripe patterns were elongated. Here we show that Piezo1 function is involved in cell spreading. Inhibiting the Rho-ROCK pathway also reversibly inhibited cell extension indicating that myosin contractility is involved. Piezo1 expressing HEK cells plated on fibronectin stripes elongated, while a knockout of Piezo1 eliminated elongation. Inhibiting Piezo1 conductance using GsMTx4 or Gd3+ blocked cell spreading, but the cells grew thin tail-like extensions along the patterns. Images of GFP-tagged Piezo1 showed plaques of Piezo1 moving to the extrusion edges, co-localized with focal adhesions. Surprisingly, in non-spreading cells Piezo1 was located primarily on the nuclear envelope. The growth of thin extrusion tails did not occur in Piezo1 knockout cells suggesting that Piezo1 may have functions besides acting as a cation channel.

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Jetta, D., Bahrani Fard, M. R., Sachs, F., Munechika, K., Hua, S. Z.. 2020-11-20. Adherent cell remodeling on micropatterns is modulated by Piezo1 channels. https://doi.org/10.1101/2020.11.18.389106

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