PRKDC Gene

The PRKDC gene (PRKDC stands for "Protein Kinase, DNA-Activated, Catalytic Subunit") is a protein-coding gene located on chromosome 8q11.21. The gene encodes "DNA-PKcs" a subunit of a serine/threonine protein kinase that belongs to the PI3/PI4 kinase family. The second component of this protein kinase is the autoimmune antigen Ku. On its own, DNA-PKcs is inactive. It relies on Ku to reach the DNA ends to trigger there and its kinase activity. Serine/threonine protein kinase acts as a molecular sensor for DNA damage. In order to develop its catalytic properties, the protein must be bound to DNA.

Serine/threonine protein kinase can phosphorylate C1D not only in the presence of linear DNA but also in the presence of supercoiled DNA. The ability to phosphorylate p53/TP53 in the presence of supercoiled DNA is dependent on C1D.

Serine/threonine protein kinase plays a role in regulating the DNA virus-mediated innate immune response by assembling into the HDP-RNP complex, a complex that serves as a platform for IRF3 phosphorylation and subsequent activation of the innate immune response via the cGAS-STING pathway.

Diseases associated with PRKDC include "immunodeficiency 26 with or without neurological abnormalities" (van der Burg M et al 2009).

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