Assignment of the 160-kDa subunit of cleavage and polyadenylation specificity factor (CPSF1) to human chromosome 8q24.23 by radiation hybrid mapping.

Eukaryotic mRNA precursors are processed at their 3) ends by the tightly coupled cleavage and polyadenylation reactions, resulting in the addition of the poly(A) tail. Cleavage and Polyadenylation Specificity Factor (CPSF) plays a key role in both these reactions and consists of four subunits of 160, 100, 73 and 30 kDa (Wahle and Kuhn, 1997). CPSF, CstF (Cleavage stimulation Factor), CF Im (Cleavage Factor I), CF IIm (Cleavage Factor II), PAP (Poly(A) polymerase) and PABP2 (PolyA Binding Protein 2) are parts of a multicomponent complex sufficient to complete the 3) processing reactions. The largest 160kDa CPSF subunit binds to the highly conserved polyadenylation signal (AAUAAA) located upstream of the cleavage site (Keller et al., 1991). It also interacts directly with the 77-kDa subunit of the CstF and with PAP (Wahle and Rüegsegger, 1999). The full length of the human CPSF 160-kDa subunit cDNA (accession number U37012) was cloned by Murthy and Manley (1995), while the bovine homologue was cloned by Jenny and Keller (1995) (accession number AAC50293). A pseudogene of the CPSF1 gene has been assigned to chromosome 22 (Dunham et al., 1999). Materials and methods