CTD small phosphatase 1 (CTDSP1)

CTD small phosphatase 1 (CTDSP1, also known as SCP1) is a member of the small C-terminal domain phosphatase family and acts as a nuclear protein phosphatase[2][4]. Its primary molecular function is the site-selective dephosphorylation of phospho-Ser5 residues of the carboxy-terminal domain (CTD) heptapeptide repeats of RNA polymerase II, regulating the transcription cycle[2][4][5]. CTDSP1 is recruited by the REST (RE-1 Silencing Transcription Factor) complex to mediate neuronal gene silencing in non-neuronal cells and controls several aspects of cell differentiation, cell cycle progression, and neurotrophic factor expression, especially following nerve injury[2][4][6][8]. Evidence suggests it may function as a tumor suppressor by inhibiting migration and invasion of cancer cells and modulating angiogenesis through interactions with the AKT pathway[2]. Research targeting CTDSP1 focuses on its potential as a therapeutic target in cancer and neural regenerative medicine, but no drugs are currently approved specifically for clinical modulation of CTDSP1[2][3][4][6].

Other names

SCP1CTDSP1Small CTD phosphatase 1CTD (carboxy-terminal domain, RNA polymerase II, polypeptide A) small phosphatase 1TFIIF-associating CTD phosphatase 1SCPNFCP1 family memberCTDS1_HUMAN

Inhibitors would act via blocking the dephosphorylation of Ser5 residues in the CTD of RNA polymerase II or interfering with REST complex recruitment, affecting transcriptional repression of neuronal or other target genes. Modulation of phosphorylation/dephosphorylation states of substrates such as RNA polymerase II or AKT, influencing downstream transcriptional and oncogenic pathways.