Homeodomain-interacting protein kinase 1 (HIPK1) belongs to the Ser/Thr family of protein kinases and HIPK subfamily. It phosphorylates homeodomain transcription factors and may also function as a co-repressor for homeodomain transcription factors. HIPKs contribute to regulate several biological processes, such as signal transduction, apoptosis, embryonic development, DNA-damage response, and cellular proliferation, in response to various extracellular stimuli. And HIPK1 has been shown to interact with P53.