Involved in histone 3'-end pre-mRNA processing by associating with U7 snRNP and interacting with SLBP/pre-mRNA complex. Increases histone 3'-end pre-mRNA processing but has no effect on U7 snRNP levels, when overexpressed. Required for cell cycle progression from G1 to S phases (By similarity). Interacts with the SLBP/pre-mRNA complex but not with SLBP alone. Interacts with LSM11 in a U7 snRNP-dependent manner (By similarity). Stable component of Cajal bodies (CBs). Colocalizes with SMN, coilin and U7 snRNA (By similarity). The C2H2-type zinc fingers are involved in discrete Cajal bodies localization, interaction with LSM11 and the SLBP/RNA complex and histone pre-mRNA processing. Belongs to the krueppel C2H2-type zinc-finger protein family.