SSRP1
Description
The SSRP1 (structure specific recognition protein 1) is a protein-coding gene located on chromosome 11.
SSRP1, also known as structure-specific recognition protein 1, is a protein encoded by the SSRP1 gene in humans. It is a subunit of the FACT complex, which along with SUPT16H, acts as a chromatin transcriptional elongation factor. FACT interacts specifically with histones H2A/H2B to facilitate nucleosome disassembly and transcription elongation. The protein contains a high mobility group box, likely responsible for recognizing cisplatin-modified DNA. This suggests a role for FACT and cisplatin-damaged DNA in the anticancer mechanism of cisplatin. SSRP1 also functions as a co-activator of the transcriptional activator p63. SSRP1 has been shown to interact with NEK9 and p63, enhancing the activity of full-length p63 but not the N-terminus-deleted variant (DeltaN-p63).
SSRP1 is a subunit of the FACT complex, a chromatin remodeling factor involved in multiple DNA-dependent processes like mRNA elongation, DNA replication, and repair. During transcription, FACT acts as a histone chaperone, destabilizing and re-establishing nucleosome structure to facilitate RNA polymerase II passage. It also promotes dissociation of the H2A-H2B dimer from the nucleosome, and subsequently helps re-establish the nucleosome after RNA polymerase II has passed. The FACT complex may also play a role in phosphorylation of p53/TP53 through its association with CK2. SSRP1 binds specifically to double-stranded DNA and to DNA modified by the antitumor agent cisplatin, potentially enhancing cisplatin-induced cell death by blocking replication and repair of modified DNA. It also functions as a transcriptional coactivator for p63/TP63.
SSRP1 is also known as FACT, FACT80, T160.
