Disease relevance of PRPS2

• The enzyme complex was then partially reconstituted in situ by coexpression of PAP39 with PRS I or PRS II in E. coli cells [1].

High impact information on PRPS2

• PRSII was less sensitive to feedback inhibition by purine nucleotides and more sensitive to inhibition by 2,3-diphosphoglycerate than PRSI [2].
• PRSI and PRSII also differed significantly in Km values for MgATP and ribose 5-phosphate, pH optima, and Mg2+ and Pi activation curves [2].
• A cDNA clone of PRPS3 was sequenced and found to encode a predicted product of 317 amino acids which was highly homologous to those of PRPS1 and PRPS2 (94.3% and 91.2% identities, respectively) [3].
• Human genes for PRS I and PRS II are localized at different regions on the X-chromosome and their promoter regions were examined [4].
• Cloning of cDNA for the catalytic subunit revealed the presence of two highly homologous isoforms of 34 kDa, designated as PRS I and PRS II [4].

Biological context of PRPS2

• Cloned cDNAs representing the entire, homologous (80%) translated sequences of human phosphoribosylpyrophosphate synthetase (PRS) 1 and PRS 2 cDNAs were utilized as probes to localize the corresponding human PRPS1 and PRPS2 genes, previously reported to be X chromosome linked [5].
• The promoter region of the human PRPS2 gene was also GC-rich and contained a TATA-like sequence, four Sp1 binding sites and a homopyrimidine stretch [6].
• Evaluation of PRPS2 expression in somatic cell hybrids containing inactive human X chromosomes showed that PRPS2 undergoes X-inactivation [7].
• Two highly homologous subunits for phosphoribosylpyrophosphate synthetase are encoded by human X-linked genes, PRPS1 and PRPS2 (Taira, M., Kudoh, J., Minoshima, S., Iizasa, T., Shimada, H., Shimizu, Y., Tatibana, M., and Shimizu, N. (1989b) Somat. Cell Mol. Genet. 15, 29-37) [3].
• The deduced amino acid sequence of PAP39 is remarkably similar to those of PRS I and PRS II [4].

Anatomical context of PRPS2

• The 2.3 kb PRPS1 mRNA level was high in the brain and adrenal gland, whereas the 3.7 kb PRPS2 mRNA level prevailed in the lung and spleen [8].
• Chloramphenicol acetyltransferase (CAT)/promoter fusion assays showed that a 2.0 kb region (human PRPS1) and a 1.1 kb region (human PRPS2) possessed the promoter activities in four cell lines [6].

Associations of PRPS2 with chemical compounds

• Cloning of cDNAs for human phosphoribosylpyrophosphate synthetases 1 and 2 and X chromosome localization of PRPS1 and PRPS2 genes [5].

Physical interactions of PRPS2

• PAP39 complexed with PRS I was more readily degraded by proteolysis than seen with PRS II, in vivo and in vitro [1].

Other interactions of PRPS2

• PRPS1 and PRPS2 loci mapped to the intervals Xq22-q24 and Xp22.2-p22.3, respectively, using a combination of in situ chromosomal hybridization and human x rodent somatic cell panel genomic DNA hybridization analyses [5].
• Complementary DNA clones for phosphoribosylpyrophosphate synthetase subunits I and II (PRS I and PRS II) were used to determine the chromosomal localization of the corresponding human genes [9].

References