Table 1.

The core polyadenylation machinery.

Factor	Subunits	Necsessary for	Interactions with other core factors	Target cis-element	Reference
CPSF	CPSF-30, CPSF-73, CPSF-100, CPSF-160, hFip1, Wdr33, and symplekin	Cleavage step and polyadenylation step	CstF, CF-II, and PAP	The PAS (AAUAAA), binding mediated by CPSF-160	Murthy and Manley (1995), Chan et al. (2011)
CstF	CstF-50, CstF-64, and CstF-77	Cleavage step	CPSF and CF-II	The DSE (U/GU-rich), binding mediated by CstF-64	MacDonald et al. (1994), Chan et al. (2011)
CF-I	CF-I-25 and either CF-I-68 or CF-I-59	Cleavage step	CF-II and PAP	The auxiliary motif UGUA	Venkataraman et al. (2005), Chan et al. (2011)
CF-II	hPcf11 and hClp1	Cleavage step	CPSF, CstF, and CF-I	None	Chan et al. (2011)
PAP	None	Cleavage step and polyadenylation step	CPSF and CF-I	None	Chan et al. (2011)