D site-binding protein (DBP) belongs to the PAR (Proline and Acidic amino acid-Rich basic leucine ZIPper) transcription factor family, which consists of HLF, DBP and TEF proteins []. DBP may bind DNA specifically as a homodimer or as a heterodimer with other PAR factors. It accumulates in the liver according to a very strong circadian rhythm regulated by hormones [].
This entry includes the major DNA-binding protein (DBP, UL57 or ICP8) from Herpesviruses. DBP binds single-stranded DNA, and the region encompassing residues 368-902 contains the DNA-binding site []. UL5, UL8 and UL52 genes encode an essential heterotrimeric DNA helicase-primase that is responsible for concomitant DNA unwinding and primer synthesis at the viral DNA replication fork. DBP may stimulate DNA unwinding and enable bypass of cisplatin damaged DNA by recruiting the helicase-primase to the DNA []. DBP helps initiate DNA replication by binding to the origin-binding protein (UL9) []. It also reorganizes the host nucleus leading to the formation of prereplicative sites and replication compartments [].
This entry includes the major DNA-binding protein (DBP, UL57 or ICP8) from Herpesviruses. DBP binds single-stranded DNA, and the region encompassing residues 368-902 contains the DNA-binding site []. UL5, UL8 and UL52 genes encode an essential heterotrimeric DNA helicase-primase that is responsible for concomitant DNA unwinding and primer synthesis at the viral DNA replication fork. DBP may stimulate DNA unwinding and enable bypass of cisplatin damaged DNA by recruiting the helicase-primase to the DNA []. DBP helps initiate DNA replication by binding to the origin-binding protein (UL9) []. It also reorganizes the host nucleus leading to the formation of prereplicative sites and replication compartments [].
This entry includes the major DNA-binding protein (DBP, UL57 or ICP8) from Herpesviruses. DBP binds single-stranded DNA, and the region encompassing residues 368-902 contains the DNA-binding site []. UL5, UL8 and UL52 genes encode an essential heterotrimeric DNA helicase-primase that is responsible for concomitant DNA unwinding and primer synthesis at the viral DNA replication fork. DBP may stimulate DNA unwinding and enable bypass of cisplatin damaged DNA by recruiting the helicase-primase to the DNA []. DBP helps initiate DNA replication by binding to the origin-binding protein (UL9) []. It also reorganizes the host nucleus leading to the formation of prereplicative sites and replication compartments [].This superfamily represents the head domain found in Viral ssDNA-binding protein. The head domain interacts with the C-terminal domain (CTD) of the protein and gives the CTD structure. The CTD is involved in increasing the ssDNA binding protein's cooperativity when binding ICP8, which is believed to stimulate helicase activity. Structurally, this domain consists of 8 alpha helices [].
A number of serum transport proteins are known to be evolutionarily related,including albumin, alpha-fetoprotein, vitamin D-binding protein and afamin[, , ]. Albumin is the main protein of plasma; it binds water, cations (suchas Ca2+, Na+and K+), fatty acids, hormones, bilirubin and drugs - its mainfunction is to regulate the colloidal osmotic pressure of blood. Alphafeto-protein (alpha-fetoglobulin) is a foetal plasma protein that binds variouscations, fatty acids and bilirubin. The biological role of afamin (alpha-albumin) has not yet been characterised.Vitamin D-binding protein (DBP) is an abundant serum glycoprotein secretedby the liver; the protein transports vitamin D sterols, binds to actin, and is found on the surface of B-lymphocytes and subpopulations of T-lymphocytes[]. The full length DBP contains 476-amino acids, including a 16-aminoacid signal sequence. Sequence analysis reveals 23% similarity to albuminand to alpha-fetoprotein []. DBP contains a characteristic placement ofcysteine residues, identical to that in albumin, suggesting a similarfolding structure. Albumin and alpha-fetoprotein contain three internallyrepeated domains []. DBP shows similarity to the first two domains andhas a truncated third domain, supporting the view that DBP is a member ofthe albumin/alpha-fetoprotein multigene family []. Within the sequence, regularly-spaced disulphide bridges generate a 3-domainfolding structure, each domain containing ~170 amino acids, with 5 or 6internal disulphide bonds, as shown schematically below: +---+ +----+ +-----+| | | | | |xxCxxxxxxxxxxxxxxxxCCxxCxxxxCxxxxxCCxxxCxxxxxxxxxCxxxxxxxxxxxxxxCCxxxxCxxxx| | | | | |+-----------------+ +-----+ +---------------+
Thyrotroph embryonic factor (TEF) belongs to the PAR (Proline and Acidic amino acid-Rich basic leucine ZIPper) transcription factor family, which consists of HLF, DBP and TEF proteins []. TEF may bind DNA specifically as a homodimer or as a heterodimer with other PAR factors. It binds to the consensus sequence 5'-GTTACGTAAT-3' []. TEF is involved in the regulation of apoptotic proteins [, ]. In chicken it is known as VBP, which binds to and transactivates the vitellogenin II (VTG2) promoter [, ].
This entry represents the DNA-binding protein (DBP) from adenovirus. It plays a role in the elongation phase of viral strand displacement replication by unwinding the template in an ATP-independent fashion, employing its capacity to form multimers []. DBP is also involved in other essential functions important in the adenovirus life cycle, including viral RNA stability, virus assembly, determination of virus host range and transformation [].
Hepatic leukemia factor (HLF) belongs to the PAR (Proline and Acidic amino acid-Rich basic leucine ZIPper) transcription factor family, which consists of HLF, DBP and TEF proteins []. HLF binds DNA specifically as a homodimer or as a heterodimer with other PAR factors. It binds to the consensus sequence 5'-GTTACGTAAT-3' []. In B-precursor acute lymphoblastic leukemia (ALL), it fuses to the N terminus of the E2A protein [], and this chimeric protein promotes cell survival of t(17;19)-ALL cells by aberrantly up-regulating the expression of hematopoiesis transcription regulator LMO2 []. HLF regulates a complex multi-gene transcriptional program that involves upregulation of anti-apoptotic genes and downregulation of pro-apoptotic genes [].
