Cleavage factor polyribonucleotide kinase subunit 1 (CLP1)

Cleavage factor polyribonucleotide kinase subunit 1 (CLP1) is a multifunctional **polynucleotide kinase enzyme** that phosphorylates 5'-hydroxyl groups on a variety of polynucleotide substrates, including double-stranded RNA, single-stranded RNA, double-stranded DNA, and DNA:RNA hybrids, with a particular efficiency toward RNA substrates[1][2][3]. It is an essential component of both the **tRNA splicing endonuclease complex**—required for the maturation and ligation of tRNA exons—and the **pre-mRNA cleavage complex II (CF-II)** involved in the 3'-end processing of mRNA precursors[1][2][3]. CLP1 also plays a role in the maturation of small interfering RNAs (siRNAs). Defects in CLP1 disrupt tRNA and mRNA processing and are causatively linked to the human neurodevelopmental disease **pontocerebellar hypoplasia type 10 (PCH10)**, characterized by microcephaly and progressive neurodegeneration[1][2][5][7]. This underscores CLP1’s importance in gene expression, especially in neuronal development and survival. No specific drugs or clinical inhibitors currently target CLP1, but its essential, highly conserved enzymatic role in RNA metabolism positions it as a potential target in the modulation of RNA processing pathways[1][2][5].

Other names

Polyribonucleotide 5'-hydroxyl-kinase Clp1HEABhClp1Polyadenylation factor Clp1Polynucleotide kinase Clp1Pre-mRNA cleavage complex II protein Clp1ATP/GTP-binding protein, cleavage and polyadenylation factor I subunit 1homolog of yeast CFIA subunit Clp1p