The association of PARVA with TESK1 appears to suppress cell spreading (Lalonde et al. 2005). TESK1 can phosphorylate cofilin and promote F-actin polymerization and cell spreading (Tsumura et al., 2005 ; Toshima et al., 2001; Leeksma et al., 2002). PARVA associates with testicular protein kinase 1 (TESK1) and inhibits its activity (Lalonde et al. 2005).