Cytidine
A pyrimidine nucleoside that is composed of the base CYTOSINE linked to the five-carbon sugar D-RIBOSE.
Cytidine Deaminase
Cytidine Monophosphate
Cytidine (dihydrogen phosphate). A cytosine nucleotide containing one phosphate group esterified to the sugar moiety in the 2', 3' or 5' position.
Cytidine Triphosphate
Cytidine 5'-(tetrahydrogen triphosphate). A cytosine nucleotide containing three phosphate groups esterified to the sugar moiety.
Cytosine Nucleotides
Cytosine nucleotides are organic compounds that consist of a nitrogenous base (cytosine), a pentose sugar (ribose in RNA or deoxyribose in DNA), and at least one phosphate group, playing crucial roles in genetic information storage, transmission, and expression within nucleic acids.
Cytidine Diphosphate Diglycerides
Cytidine Diphosphate
Cytidine 5'-(trihydrogen diphosphate). A cytosine nucleotide containing two phosphate groups esterified to the sugar moiety. Synonyms: CRPP; cytidine pyrophosphate.
Somatic Hypermutation, Immunoglobulin
Cytosine Deaminase
An enzyme which catalyzes the deamination of CYTOSINE resulting in the formation of URACIL. It can also act on 5-methylcytosine to form THYMIDINE.
Immunoglobulin Class Switching
Gene rearrangement of the B-lymphocyte which results in a substitution in the type of heavy-chain constant region that is expressed. This allows the effector response to change while the antigen binding specificity (variable region) remains the same. The majority of class switching occurs by a DNA recombination event but it also can take place at the level of RNA processing.
Cytidine Diphosphate Choline
Nucleoside Deaminases
Catalyze the hydrolysis of nucleosides with the elimination of ammonia.
Cytidine Monophosphate N-Acetylneuraminic Acid
Uridine
Nucleosides
RNA Editing
A process that changes the nucleotide sequence of mRNA from that of the DNA template encoding it. Some major classes of RNA editing are as follows: 1, the conversion of cytosine to uracil in mRNA; 2, the addition of variable number of guanines at pre-determined sites; and 3, the addition and deletion of uracils, templated by guide-RNAs (RNA, GUIDE).
Pyrimidine Nucleosides
Pyrimidines with a RIBOSE attached that can be phosphorylated to PYRIMIDINE NUCLEOTIDES.
N-Acylneuraminate Cytidylyltransferase
Cyclic CMP
Uridine Kinase
Pyrimidine Nucleotides
vif Gene Products, Human Immunodeficiency Virus
Uracil Nucleotides
Uracil nucleotides are chemical compounds that consist of a uracil base, a sugar molecule called ribose, and one or more phosphate groups, which play crucial roles in DNA replication, repair, and gene expression as well as in RNA synthesis.
Immunoglobulin Switch Region
A site located in the INTRONS at the 5' end of each constant region segment of a immunoglobulin heavy-chain gene where recombination (or rearrangement) occur during IMMUNOGLOBULIN CLASS SWITCHING. Ig switch regions are found on genes encoding all five classes (IMMUNOGLOBULIN ISOTYPES) of IMMUNOGLOBULIN HEAVY CHAINS.
Carbon-Nitrogen Ligases
Base Sequence
3-Deazauridine
4-Hydroxy-1-(beta-D-ribofuranosyl)-2-pyridinone. Analog of uridine lacking a ring-nitrogen in the 3-position. Functions as an antineoplastic agent.
Guanosine
A purine nucleoside that has guanine linked by its N9 nitrogen to the C1 carbon of ribose. It is a component of ribonucleic acid and its nucleotides play important roles in metabolism. (From Dorland, 28th ed)
Molecular Sequence Data
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Gene Products, vif
Aminohydrolases
Aminohydrolases are a class of enzymes that catalyze the hydrolysis of various nitrogenous compounds, including proteins, nucleotides, and amines, playing a crucial role in numerous biological processes such as metabolism and signaling.
B-Lymphocytes
Nucleotides
DCMP Deaminase
An enzyme that catalyzes the hydrolytic deamination of deoxycytidylic acid to deoxyuridylic acid and ammonia. It plays an important role in the regulation of the pool of deoxynucleotides in higher organisms. The enzyme also acts on some 5-substituted deoxycytidylic acids. EC 3.5.4.12.
Deoxycytidine
Ribonucleosides
Uracil
Uracil is a nitrogenous base, specifically a pyrimidine derivative, which constitutes one of the four nucleobases in the nucleic acid of RNA (ribonucleic acid), pairing with adenine via hydrogen bonds during base-pairing. (25 words)
Deoxycytidine Kinase
An enzyme that catalyzes reversibly the phosphorylation of deoxycytidine with the formation of a nucleoside diphosphate and deoxycytidine monophosphate. Cytosine arabinoside can also act as an acceptor. All natural nucleoside triphosphates, except deoxycytidine triphosphate, can act as donors. The enzyme is induced by some viruses, particularly the herpes simplex virus (HERPESVIRUS HOMINIS). EC 2.7.1.74.
Hyper-IgM Immunodeficiency Syndrome
A rare inherited immunodeficiency syndrome characterized by normal or elevated serum IMMUNOGLOBULIN M levels with absence of IMMUNOGLOBULIN G; IMMUNOGLOBULIN A; and IMMUNOGLOBULIN E. It results in a profound susceptibility to BACTERIAL INFECTIONS and an increased susceptibility to OPPORTUNISTIC INFECTIONS. Several subtypes of hyper-IgM immunodeficiency syndrome exist depending upon the location of genetic mutation.
Uridine Monophosphate
5'-Uridylic acid. A uracil nucleotide containing one phosphate group esterified to the sugar moiety in the 2', 3' or 5' position.
Mutation
RNA
A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Germinal Center
The activated center of a lymphoid follicle in secondary lymphoid tissue where B-LYMPHOCYTES are stimulated by antigens and helper T cells (T-LYMPHOCYTES, HELPER-INDUCER) are stimulated to generate memory cells.
Inosine
A purine nucleoside that has hypoxanthine linked by the N9 nitrogen to the C1 carbon of ribose. It is an intermediate in the degradation of purines and purine nucleosides to uric acid and in pathways of purine salvage. It also occurs in the anticodon of certain transfer RNA molecules. (Dorland, 28th ed)
Nucleoside Diphosphate Sugars
Orotic Acid
Orotic acid, also known as pyrophosphoric acid dihydrate, is a organic compound that plays a role in the biosynthesis of pyrimidines, and elevated levels of orotic acid in urine can indicate certain genetic disorders or liver dysfunction.
Deoxyuridine
2'-Deoxyuridine. An antimetabolite that is converted to deoxyuridine triphosphate during DNA synthesis. Laboratory suppression of deoxyuridine is used to diagnose megaloblastic anemias due to vitamin B12 and folate deficiencies.
Cytarabine
A pyrimidine nucleoside analog that is used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia. Cytarabine is an antimetabolite antineoplastic agent that inhibits the synthesis of DNA. Its actions are specific for the S phase of the cell cycle. It also has antiviral and immunosuppressant properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p472)
Deoxycytidine Monophosphate
Nucleic Acid Conformation
Uracil-DNA Glycosidase
Escherichia coli
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Nucleoside-Phosphate Kinase
Genes, Immunoglobulin Heavy Chain
Genes and gene segments encoding the IMMUNOGLOBULIN HEAVY CHAINS. Gene segments of the heavy chain genes are symbolized V (variable), D (diversity), J (joining), and C (constant).
Uridine Phosphorylase
Deoxycytosine Nucleotides
Cytosine nucleotides which contain deoxyribose as the sugar moiety.
DNA
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Deoxyadenosines
Sialyltransferases
A group of enzymes with the general formula CMP-N-acetylneuraminate:acceptor N-acetylneuraminyl transferase. They catalyze the transfer of N-acetylneuraminic acid from CMP-N-acetylneuraminic acid to an acceptor, which is usually the terminal sugar residue of an oligosaccharide, a glycoprotein, or a glycolipid. EC 2.4.99.-.
RNA, Transfer, Ile
A transfer RNA which is specific for carrying isoleucine to sites on the ribosomes in preparation for protein synthesis.
Apolipoproteins B
Major structural proteins of triacylglycerol-rich LIPOPROTEINS. There are two forms, apolipoprotein B-100 and apolipoprotein B-48, both derived from a single gene. ApoB-100 expressed in the liver is found in low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). ApoB-48 expressed in the intestine is found in CHYLOMICRONS. They are important in the biosynthesis, transport, and metabolism of triacylglycerol-rich lipoproteins. Plasma Apo-B levels are high in atherosclerotic patients but non-detectable in ABETALIPOPROTEINEMIA.
Substrate Specificity
Ribonucleotides
Arabinofuranosylcytosine Triphosphate
A triphosphate nucleotide analog which is the biologically active form of CYTARABINE. It inhibits nuclear DNA synthesis.
Uridine Triphosphate
Uridine 5'-(tetrahydrogen triphosphate). A uracil nucleotide containing three phosphate groups esterified to the sugar moiety.
Oligoribonucleotides
A group of ribonucleotides (up to 12) in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.
Azacitidine
Genes, Immunoglobulin
Genes encoding the different subunits of the IMMUNOGLOBULINS, for example the IMMUNOGLOBULIN LIGHT CHAIN GENES and the IMMUNOGLOBULIN HEAVY CHAIN GENES. The heavy and light immunoglobulin genes are present as gene segments in the germline cells. The completed genes are created when the segments are shuffled and assembled (B-LYMPHOCYTE GENE REARRANGEMENT) during B-LYMPHOCYTE maturation. The gene segments of the human light and heavy chain germline genes are symbolized V (variable), J (joining) and C (constant). The heavy chain germline genes have an additional segment D (diversity).
Deoxyribonucleotides
Immunoglobulin Heavy Chains
Amino Acid Sequence
Phosphotransferases
HIV-1
Oligonucleotides
Polymers made up of a few (2-20) nucleotides. In molecular genetics, they refer to a short sequence synthesized to match a region where a mutation is known to occur, and then used as a probe (OLIGONUCLEOTIDE PROBES). (Dorland, 28th ed)
Poly C
A group of cytosine ribonucleotides in which the phosphate residues of each cytosine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.
Genes, Immunoglobulin Light Chain
Recombination, Genetic
Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.
Electrophoresis, Paper
Electrophoresis in which paper is used as the diffusion medium. This technique is confined almost entirely to separations of small molecules such as amino acids, peptides, and nucleotides, and relatively high voltages are nearly always used.