Talin promotes integrin activation accompanied by generation of tension in talin and an increase in osmotic pressure in neurite outgrowth

Abstract

Neuronal polarization depends on the interaction of intracellular chemical and mechanical activities in which the cytoplasmic protein, talin, plays a pivotal role during neurite growth. To better understand the mechanism underlying talin function in neuronal polarization, we overexpressed several truncated forms of talin and found that the presence of the rod domain within the overexpressed talin is required for its positive effect on neurite elongation because the neurite number only increased when the talin head region was overexpressed. The tension in the talin rod was recognized using a Förster resonance energy transfer‐based tension probe. Nerve growth factor treatment resulted in inward tension of talin elicited by microfilament force and outward osmotic pressure. By contrast, the glial scar‐inhibitor aggrecan weakened these forces, suggesting that interactions between inward pull forces in the talin rod and outward osmotic pressure participate in neuronal polarization. Integrin activation is also involved in up‐regulation of talin tension and osmotic pressure. Aggrecan stimuli resulted in up‐regulation of docking protein 1 (DOK1), leading to the down‐regulation of integrin activity and attenuation of the intracellular mechanical force. Our study suggests interactions between the intracellular inward tension in talin and the outward osmotic pressure as the effective channel for promoting neurite outgrowth, which can be up‐regulated by integrin activation and down‐regulated by DOK1.—Wang, Y., Zhang, X., Tian, J., Shan, J., Hu, Y., Zhai, Y., Guo, J. Talin promotes integrin activation accompanied by generation of tension in talin and an increase in osmotic pressure in neurite outgrowth. FASEB J. 33, 6311–6326 (2019). http://www.fasebj.org

Inward Tension of Talin and Integrin-related Osmotic Pressure are involved Synergetically in the Invasion and Metastasis of Non-small Cell Lung Cancer

“…A GFAP-cpst-GFAP probe was constructed and transfected into A549 cells by a previously reported method [20][21][22], revealing that GFAP tension and cytoplasmic osmotic pressure increase upon EGF treatment (Fig. 3A,B).…”

“…Osmotic pressure was measured as reported previously [21,22]. Namely, the cells were broken using an ultrasonic crusher for 1min (VCX150; Sonics, Newtown, CT, USA), and then centrifuged at 13,000 g for 10 min at 4 °C.…”

“…The effectiveness of FRET in the stable monoclonal cell line was determined by the dipole angle between the donor (eCFP) and the acceptor (eYFP). Thereafter, the FRET analysis was conducted as reported in previous works [20][21][22]. We calculated the CPF/FRET ratio, which is negatively correlated with FRET efficiency and positively correlated with force, using the relationship E = eCFP donor/eYFP acceptor.…”

Protein Nanoparticle Osmotic Pressure Modifies Nonselective Permeability of the Blood Brain Barrier by Increasing Membrane Fluidity

“…NovoRec PCR seamless cloning and assembly kit (Thermo Fisher Scienti c) and restriction endonuclease cloning methods were used to construct the FRET-based probes, as described previously [12][13][14][15] . The occludin (#86042) and ZO1 (#30313) genes were purchased from Addgene (Watertown, MA, USA).…”

“…Under the effect of dynamic molecules, MF and MT can produce cytoskeletal forces. The osmotic pressure (OP) difference across the membrane can produce tension by pulling the intermediate lament (IF) [10,14] . However, the mechanisms by which cytoskeletal forces and osmotic pressure regulate the mobility of transmembrane proteins and permeability of the BBB remain unclear.…”