KRIT1 and cerebral cavernous malformation: Two additional NPXY/F motifs located in the central region of KRIT1 (aa 208–417) have been demonstrated to be required for KRIT1 interaction with CCM2 [14], [16], and subsequently it has been shown that through this interaction KRIT1 regulates vascular permeability by suppressing the RhoA-ROCK signaling pathway, strongly dysregulated in human CCM endothelium [22], [23].