Based on sequence similarities a domain of homology has been identified near
the N- or C-terminal end of the following proteins [1,2,3]:
Citron Rho-interacting kinase (CRIK). It interacts with the GTP-bound forms
of the small GTPases Rho and Rac, but not with Cdc42.
Myotonic dystrophy kinase-related Cdc42-binding kinase (MRCKα). This
serine/threonine kinase interacts with the GTP-bound form of the small
GTPase Cdc42 and to a lesser extent with that of Rac.
NCK Interacting Kinase (NIK), a serine/threonine protein kinase.
Yeast ROM-1 and ROM-2. These proteins are GDP/GTP exchange proteins (GEPs)
for the small GTP binding protein Rho1.
Eukaryotic Vam6/Vps39 protein. It may function as a tethering/docking
factor specifically involved in lysosome fusion.
Little is known about the function of the CNH domain, although it has been
proposed to regulate kinase activity and to mediate binding to the GTP-bound
forms of Rac and Rho. The CNH domain is required for association with
lysosomes and overexpression-induced lysosome clustering and fusion. It could
interact with a docking protein or with lipids on the lysosomal membrane .
The profile we developed covers the entire CNH domain.
September 2009 / First entry.
PROSITE method (with tools and information) covered by this documentation:
Su Y.-C. Han J. Xu S. Cobb M. Skolnik E.Y.
NIK is a new Ste20-related kinase that binds NCK and MEKK1 and activates the SAPK/JNK cascade via a conserved regulatory domain.
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