Xeroderma pigmentosum (XP) []is a human autosomal recessive disease,characterised by a high incidence of sunlight-induced skin cancer. Skin cells of individual's with this condition are hypersensitive to ultraviolet light, dueto defects in the incision step of DNA excision repair. There are a minimum ofseven genetic complementation groups involved in this pathway: XP-A to XP-G.XP-A is the most severe form of the disease and is due to defects in a 30kDanuclear protein called XPA (or XPAC) [].The sequence of the XPA protein is conserved from higher eukaryotes []toyeast (gene RAD14) []. XPA is a hydrophilic protein of 247 to 296 amino-acidresidues which has a C4-type zinc finger motif in its central section.
Xeroderma pigmentosum (XP) []is a human autosomal recessive disease,characterised by a high incidence of sunlight-induced skin cancer. Skin cells of individual's with this condition are hypersensitive to ultraviolet light, dueto defects in the incision step of DNA excision repair. There are a minimum ofseven genetic complementation groups involved in this pathway: XP-A to XP-G.XP-A is the most severe form of the disease and is due to defects in a 30kDanuclear protein called XPA (or XPAC) [].The sequence of the XPA protein is conserved from higher eukaryotes []toyeast (gene RAD14) []. XPA is a hydrophilic protein of 247 to 296 amino-acidresidues which has a C4-type zinc finger motif in its central section.This superfamily represents a domain of the XPA protein.
Xeroderma pigmentosum (XP) []is a human autosomal recessive disease,characterised by a high incidence of sunlight-induced skin cancer. Skin cells of individual's with this condition are hypersensitive to ultraviolet light, dueto defects in the incision step of DNA excision repair. There are a minimum ofseven genetic complementation groups involved in this pathway: XP-A to XP-G.XP-A is the most severe form of the disease and is due to defects in a 30kDanuclear protein called XPA (or XPAC) [].The sequence of the XPA protein is conserved from higher eukaryotes []toyeast (gene RAD14) []. XPA is a hydrophilic protein of 247 to 296 amino-acidresidues which has a C4-type zinc finger motif in its central section.This entry contains the zinc-finger containing region in the XPA protein. It is found N-terminal to ()
Xeroderma pigmentosum (XP) []is a human autosomal recessive disease,characterised by a high incidence of sunlight-induced skin cancer. Skin cells of individual's with this condition are hypersensitive to ultraviolet light, dueto defects in the incision step of DNA excision repair. There are a minimum ofseven genetic complementation groups involved in this pathway: XP-A to XP-G.XP-A is the most severe form of the disease and is due to defects in a 30kDanuclear protein called XPA (or XPAC) [].The sequence of the XPA protein is conserved from higher eukaryotes []toyeast (gene RAD14) []. XPA is a hydrophilic protein of 247 to 296 amino-acidresidues which has a C4-type zinc finger motif in its central section.This entry represents the uncharacterised C-terminal domain of the XPA protein.
Xeroderma pigmentosum (XP) []is a human autosomal recessive disease,characterised by a high incidence of sunlight-induced skin cancer. Skin cells of individual's with this condition are hypersensitive to ultraviolet light, dueto defects in the incision step of DNA excision repair. There are a minimum ofseven genetic complementation groups involved in this pathway: XP-A to XP-G.XP-A is the most severe form of the disease and is due to defects in a 30kDanuclear protein called XPA (or XPAC) [].The sequence of the XPA protein is conserved from higher eukaryotes []toyeast (gene RAD14) []. XPA is a hydrophilic protein of 247 to 296 amino-acidresidues which has a C4-type zinc finger motif in its central section.This entry corresponds to the second conserved site in the XPA protein. It is a highly conserved region located some 12 residues after the zinc finger region
GPN-loop GTPase 1 (Gpn1) belongs to the GPN-loop GTPase family []. It is also known as Npa3 in budding yeasts and XAB1 in humans.Npa3 has GTPase activity that is essential for its binding to RNA polymerase II (RNAPII) and the nuclear localisation of RNAPII [].XAB1 is a cytoplasmic GTPase involved in nuclear localisation of DNA repair protein XPA []. This entry also includes archaeal GPN-loop GTPases, such as PYRAB14380 from Pyrococcus abyssi [].
A putative DNA-binding domain with a conserved structure is found in several different protein families. The core structure of the domain consists of a three-helical fold that is architecturally similar to that of the "winged-helix"fold, but is topologically distinct. Representatives of this domain can be found in domains B1 and B5 from the beta subunit of phenylalanine-tRNA synthetases [], the C-terminal region of the DNA/RPA-binding domain of the DNA excision repair factor XPA [], the N-terminal domain of the transcriptional activators BmrR and MtaN [], the most conserved domain of the retinal development protein Dachshund [], and the DNA-binding domain of the gpNU1 subunit from the bacteriophage lambda viral packing protein terminase [].
The function of this domain is yet to be characterised. It is often found in eukaryotes, and is approximately 70 amino acids in length. It has a conserved DPE sequence motif. This domain is putatively thought to lie in the C terminus of the DNA nucleotide repair protein, Xeroderma pigmentosa complementation group A (XPA). The function of XPA is to bind to DNA and repair any mismatched base pairs. In humans, this protein is encoded for in chromosome 5 open reading frame 65. Mutations in the gene lead to myelodysplastic syndromes, where there is inefficient stem cell production in the bone marrow. This suggests that the protein may have a role in forming blood cells [].
