In molecular biology, the kinase binding protein CGI-121 family of proteins includes the kinase binding protein CGI-121 and its homologues.

CGI-121 has been shown to bind to the p53-related protein kinase (PRPK).

[1] CGI-121 is part of a conserved protein complex, KEOPS.

The KEOPS complex is involved in telomere uncapping and telomere elongation.

[2] This family of proteins also include archaeal homologues.