Involved in DNA replication and the cellular response to DNA damage. May participate in DNA replication factories and create a bridge between DNA replication and repair mediated by high molecular weight complexes. May play a role in illegitimate recombination and regulation of gene expression. May participate in mRNA processing. Binds, in vitro, to double-stranded DNA. Also shown to bind preferentially to curved DNA in vitro and in vivo (By similarity). Binds via its C-terminal domain to RNA in vitro. Associated with DNA polymerase alpha, RFC1 and cyclin A, in multiprotein DNA replication complexes. Also associates with replication origins at the G1/S phase boundary and throughout the S phase in vivo. (Microbial infection) Interacts with SV40 large T antigen. During S phase, strongly associated with the nuclear matrix, and to chromosomal DNA in the presence of DNA damage. Also shows cytoplasmic localization in elongated spermatids. Ubiquitously expressed in all tissues examined, with highest levels in skeletal muscle, heart and testis. Differentially expressed in non-tumorigenic and tumorigenic cell lines. Highly expressed in proliferating epithelial keratinocyte cells in vitro (at protein level). By UVC irradiation in quiescent primary fibroblasts. By mitomycin C in human melanoma MeWO cells. The C-terminal domain (268-393) is organized into 2 subdomains that bear structural similarities to SH3-like domains. Both subdomains adopt a similar 5-stranded beta-barrel-like fold and are connected to each other by a short linker of 5 residues. The 5 beta-sheets are packed at approximately right angles against each other. A highly conserved groove formed at the interface between the 2 subdomains, comprised of Lys residues 302 and 391 and other positively charged residues, may possibly be the site of RNA-binding. Recognized by antibodies directed against the RecA protein. Belongs to the KIN17 family.