TRPV4 participates in the establishment of trailing adhesions and directional persistence of migrating cells

• Published in: Pflügers Archiv 2015-10, Vol.467 (10), p.2107-2119
• Main Authors: Mrkonjić, Sanela, Garcia-Elias, Anna, Pardo-Pastor, Carlos, Bazellières, Elsa, Trepat, Xavier, Vriens, Joris, Ghosh, Debapriya, Voets, Thomas, Vicente, Rubén, Valverde, Miguel A.
• Format: Article
• Language: English
• Subjects: Binding Sites; Biomedical and Life Sciences; Biomedicine; Calpain - metabolism; Cell Adhesion; Cell Behavior; Cell Biology; Cell Line, Tumor; Cell Membrane Structures - metabolism; Cell Movement; Cellular Biology; HEK293 Cells; Human Physiology; Humans; Ion Channels; Life Sciences; Molecular Medicine; Mutation; Neurosciences; Phosphatidylinositols - metabolism; Protein Binding; Receptors; Receptors and Transporters; Subcellular Processes; TRPV Cation Channels - chemistry; TRPV Cation Channels - genetics; TRPV Cation Channels - metabolism
• ISSN: 0031-6768; 1432-2013
• DOI: 10.1007/s00424-014-1679-8

Calcium signaling participates in different cellular processes leading to cell migration. TRPV4, a non-selective cation channel that responds to mechano-osmotic stimulation and heat, is also involved in cell migration. However, the mechanistic involvement of TRPV4 in cell migration is currently unknown. We now report that expression of the mutant channel TRPV4- 121 AAWAA (lacking the phosphoinositide-binding site 121 KRWRK 125 and the response to physiological stimuli) altered HEK293 cell migration. Altered migration patterns included periods of fast and persistent motion followed by periods of stalling and turning, and the extension of multiple long cellular protrusions. TRPV4-WT overexpressing cells showed almost complete loss of directionality with frequent turns, no progression, and absence of long protrusions. Traction microscopy revealed higher tractions forces in the tail of TRPV4- 121 AAWAA than in TRPV4-WT expressing cells. These results are consistent with a defective and augmented tail retraction in TRPV4- 121 AAWAA- and TRPV4-WT-expressing cells, respectively. The activity of calpain, a protease implicated in focal adhesion (FA) disassembly, was decreased in TRPV4- 121 AAWAA compared with TRPV4-WT-expressing cells. Consistently, larger focal adhesions were seen in TRPV4- 121 AAWAA compared with TRPV4-WT-expressing HEK293 cells, a result that was also reproduced in T47D and U87 cells. Similarly, overexpression of the pore-dead mutant TRPV4-M680D resumed the TRPV4- 121 AAWAA phenotype presenting larger FA. The migratory phenotype obtained in HEK293 cells overexpressing TRPV4- 121 AAWAA was mimicked by knocking-down TRPC1, a cationic channel that participates in cell migration. Together, our results point to the participation of TRPV4 in the dynamics of trailing adhesions, a function that may require the interplay of TRPV4 with other cation channels or proteins present at the FA sites.