ribonucleotide

Phosphoribosylformylglycinamidine synthase involved in the purines biosynthetic pathway. Catalyzes the ATP-dependent conversion of formylglycinamide ribonucleotide (FGAR) and glutamine to yield formylglycinamidine ribonucleotide (FGAM) and glutamate. PFAS Protein, Human, Recombinant (His & Myc & SUMO) is expressed in E. coli expression system with N-10xHis-SUMO and C-Myc tag. The predicted molecular weight is 45.4 kDa and the accession number is O15067.

Ribonucleoside-Diphosphate Reductase Subunit M2 (RRM2) belongs to the ribonucleoside diphosphate reductase small chain family. The reductase of RRM2 catalyzes the formation of deoxyribonucleotides from ribonucleotides. Synthesis of the encoded protein (M2) is regulated in a cell-cycle dependent fashion. RRM2 supplies the precursors essential for DNA synthesis. RRM2 catalyzes the biosynthesis of deoxyribonucleotides from the corresponding ribonucleotides. Phosphorylation on Ser-20 relieves the inhibitory effect on Wnt signaling.

RRM1 is a subunit of ribonucleoside-diphosphate reductase which is constituted by two subunits. Ribonucleoside-diphosphate reductase is an enzyme essential for the production of deoxyribonucleotides prior to DNA synthesis in S phase of dividing cells. RRM1 is one of several genes located in the imprinted gene domain of 11p15.5, an important tumor-suppressor gene region. Alterations in this region have been associated with the Beckwith-Wiedemann syndrome, Wilms tumor, rhabdomyosarcoma, adrenocortical carcinoma, and lung, ovarian, and breast cancer. RRM1 may play a role in malignancies and disease that involve this region.

Ribonucleoside reductase subunit M2B, also known as RRM2B or p53R2, is an enzyme belonging to the iron-dependent ribonucleotide reductase (RNR) enzyme family which is essential for DNA synthesis. Ribonucleotide reductase (RNR) is an enzyme that catalyzes the formation of deoxyribonucleotides from ribonucleotides and plays a critical role in regulating the total rate of DNA synthesis so that DNA to cell mass is maintained at a constant ratio during cell division and DNA repair. RRM2B is a phosphorylated protein. It is hypothesized that RRM2B activity can be regulated at the posttranslational level in response to DNA damage. RRM2B has previously been shown to be essential for the maintenance of mtDNA copy number and its candidacy for tumor suppression has been evaluated in several mutational analyses of different cancer types. However, the contribution of RRM2B to the DNA damage response has been questioned because its transcriptional induction upon DNA damage is not rapid enough for prompt DNA repair. Instead, ATM-mediated phosphorylation has been suggested to regulate the DNA repair activity of RRM2B posttranslationally. Besides, a defect in RRM2B can induce a mild muscle disease of adult onset through disturbance of mitochondrial homeostasis but that this defect does not appear to be oncogenic.

Glutaredoxin-1, also known as GRX1 and GLRX, belongs to theglutaredoxin family. Glutaredoxinsare smallredoxenzymes that useglutathioneas a cofactor. Glutaredoxins are oxidized by substrates, and reduced non-enzymatically by glutathione. Glutaredoxin-1 functions as an electron carrier in the glutathione-dependent synthesis of deoxyribonucleotides by the enzyme ribonucleotide reductase. Glutaredoxin-1 exists in either a reduced or an oxidized form. Glutaredoxins function as electron carriers in the glutathione-dependent synthesis ofdeoxyribonucleotidesby the enzymeribonucleotide reductase.

Thioredoxin-2, also known as TXN2, MTRX and TRX2, is a member of the thioredoxin family. Tryparedoxins (TXN) are thioredoxin-related proteins which, as trypanothione:peroxiredoxin oxidoreductases, constitute the trypanothione-dependent antioxidant defense and may also serve as substrates for ribonucleotide reductase in trypanosomatids. Thioredoxin-2 TXN2 contains one thioredoxin domain. It is widely expressed in adult (at protein level) and fetal tissues. Human Thioredoxin-2 TXN2 is a small redox protein important in cellular antioxidant defenses, as well as in the regulation of apoptosis. Thioredoxin-2 TXN2 has an anti-apoptotic function and plays an important role in the regulation of mitochondrial membrane potential. Thioredoxin-2 TXN2 could be involved in the resistance to anti-tumor agents. It possesses a dithiol-reducing activity. Thioredoxin-2 TXN2 plays an important role in protecting the mitochondria against oxidative stress and in sensitizing the cells to ROS-induced apoptosis. Mammalian Thioredoxin-2 TXN2 is a mitochondrial isoform of highly evolutionary conserved thioredoxins. Thioredoxins are small ubiquitous protein-disulfide oxidoreductases implicated in a large variety of biological functions.

Nicotinate-Nucleotide Pyrophosphorylase (QPRT) belongs to the nadC modD family. QPRT plays an improtant role in catabolism of quinolinate which acts as a potent endogenous exitotoxin to neurons. In addition, QPRT serves as an an intermediate in the Tryptophan-Nicotinamide Adenine Dinucleotide pathway. QPRT participates in some pathways including Cofactor biosynthesis, NAD(+) biosynthesis and the Nicotinate D-Ribonucleotide from Quinolinate. In addition, QPRT is involved in the catabolism of Quinolinic Acid (QA). The activity toward QA is slightly repressed by phosphoribosylpyrophosphate (PRPP) in both a competitive and a non-competitive manner.

The non—structural protein 13 (nsp13) of SARS—CoV 2 is a helicase that separates double—stranded RNA or DNA with a 5'—3' polarity, using the energy of nucleotide hydrolysis. A basic biochemical characterization of nsp13 demonstrated that it can unwind both doublestranded DNA and RNA in a 5’-3’ direction, and it can hydrolyze all deoxyribonucleotide and ribonucleotide triphosphates. Helicases are motor proteins that utilize the energy derived from nucleotide hydrolysisto unwind double-stranded nucleic acids into two single-stranded nucleic acids. Initially, helicases were only thought to be molecular engines that unwind nucleic acids during replication, recombination, and DNA repair. Recent studies have shown that they are also involved in other biological processes, including displacement of proteins from nucleic acid, movement of Holliday junctions, chromatin remodeling, catalysis of nucleic acid conformational changes, several aspects of RNA metabolism, including transcription, mRNA splicing, mRNA export, translation, RNA stability and mitochondrial gene expression. Some human diseases, including Bloom’s syndrome, Werner’s syndrome, and Xeroderma Pigmentosum have been associated with defects in helicase function.