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POLA1
DNA polymerase alpha catalytic subunit is an enzyme that in humans is encoded by the ''POLA1'' gene. Function This gene encodes the p180 catalytic subunit of DNA polymerase α-primase. Pol α has limited processivity and lacks 3′ exonuclease activity for proofreading errors. Thus it is not well suited to efficiently and accurately copy long templates (unlike Pol Delta and Epsilon). Instead it plays a more limited role in replication. Pol α is responsible for the initiation of DNA replication at origins of replication (on both the leading and lagging strands) and during synthesis of Okazaki fragments on the lagging strand. The Pol α complex (pol α-DNA primase complex) consists of four subunits: the catalytic subunit POLA1, the regulatory subunit POLA2, and the small and the large primase subunits PRIM1 and PRIM2 respectively. Once primase has created the RNA primer, Pol α starts replication elongating the primer with ~20 nucleotides. Clinical significance In additio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked Reticulate Pigmentary Disorder
X-linked reticulate pigmentary disorder is a rare X-linked genetic condition in which males manifest multiple systemic symptoms and a reticulated mottled brown pigmentation of the skin, which, on biopsy, demonstrated dermal deposits of amyloid. Females usually only have linear streaks of hyperpigmentation. The syndrome is also referred to by the acronym X-Linked-PDR or XLPRD. It's a very rare disease, genetically determined, with a chronic course. It was characterized in 1981. Mutation of the ''POLA1'' gene leads to loss of expression of the catalytic subunit of DNA polymerase-α and is responsible for XLPDR. Loss of POLA1 expression results in reduced levels of RNA:DNA hybrids in the cytosol and unexpectedly triggers aberrant immune responses (e.g. type I interferon production) which at least in part can account for the symptoms associated with XLPDR. Another trigger of the immunodeficiency phenotype is a functional deficiency of NK cells, major players of innate antiviral immun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Polymerase
A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA. These enzymes are essential for DNA replication and usually work in groups to create two identical DNA duplexes from a single original DNA duplex. During this process, DNA polymerase "reads" the existing DNA strands to create two new strands that match the existing ones. These enzymes catalyze the chemical reaction : deoxynucleoside triphosphate + DNAn pyrophosphate + DNAn+1. DNA polymerase adds nucleotides to the three prime (3')-end of a DNA strand, one nucleotide at a time. Every time a cell divides, DNA polymerases are required to duplicate the cell's DNA, so that a copy of the original DNA molecule can be passed to each daughter cell. In this way, genetic information is passed down from generation to generation. Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its tightl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PARP1
Poly DP-ribosepolymerase 1 (PARP-1) also known as NAD+ ADP-ribosyltransferase 1 or poly DP-ribosesynthase 1 is an enzyme that in humans is encoded by the ''PARP1'' gene. It is the most abundant of the PARP family of enzymes, accounting for 90% of the NAD+ used by the family. PARP1 is mostly present in cell nucleus, but cytosolic fraction of this protein was also reported. Function PARP1 works: * By using NAD+ to synthesize poly ADP ribose (PAR) and transferring PAR moieties to proteins (ADP-ribosylation). * In conjunction with BRCA, which acts on double strands; members of the PARP family act on single strands; or, when BRCA fails, PARP takes over those jobs as well (in a DNA repair context). PARP1 is involved in: * Differentiation, proliferation, and tumor transformation * Normal or abnormal recovery from DNA damage * May be the site of mutation in Fanconi anemia * Induction of inflammation. * The pathophysiology of type I diabetes. PARP1 is activated by: * Helicobacte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBMS1
RNA-binding motif, single-stranded-interacting protein 1 is a protein that in humans is encoded by the ''RBMS1'' gene. Function This gene encodes a member of a small family of proteins which bind single stranded DNA/RNA. These proteins are characterized by the presence of two sets of ribonucleoprotein consensus sequence (RNP-CS) that contain conserved motifs, RNP1 and RNP2, originally described in RNA binding proteins, and required for DNA binding. These proteins have been implicated in such diverse functions as DNA replication, gene transcription, cell cycle progression and apoptosis. Multiple transcript variants, resulting from alternative splicing and encoding different isoforms, have been described. Several of these were isolated by virtue of their binding to either strand of an upstream element of c-myc (MSSPs), or by phenotypic complementation of cdc2 and cdc13 mutants of yeast (scr2), or as a potential human repressor of HIV-1 and ILR-2 alpha promoter transcription (YC1). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinoblastoma Protein
The retinoblastoma protein (protein name abbreviated pRb; gene name abbreviated ''Rb'', ''RB'' or ''RB1'') is a proto-oncogenic tumor suppressor protein that is dysfunctional in several major cancers. One function of pRb is to prevent excessive cell growth by inhibiting cell cycle progression until a cell is ready to divide. When the cell is ready to divide, pRb is phosphorylated, inactivating it, and the cell cycle is allowed to progress. It is also a recruiter of several chromatin remodeling enzymes such as methylases and acetylases. pRb belongs to the pocket protein family, whose members have a pocket for the functional binding of other proteins. Should an oncogenic protein, such as those produced by cells infected by high-risk types of human papillomavirus, bind and inactivate pRb, this can lead to cancer. The ''RB'' gene may have been responsible for the evolution of multicellularity in several lineages of life including animals. Name and genetics In humans, the prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GINS1
DNA replication complex GINS protein PSF1 is a protein that in humans is encoded by the ''GINS1'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba .... References Further reading * * * * * * * {{gene-20-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MCM4
DNA replication licensing factor MCM4 is a protein that in humans is encoded by the ''MCM4'' gene. Function The protein encoded by this gene is one of the highly conserved mini-chromosome maintenance proteins (MCM) that are essential for the initiation of eukaryotic genome replication. The hexameric protein complex formed by MCM proteins is a key component of the pre-replication complex (pre-RC) and may be involved in the formation of replication forks and in the recruitment of other DNA replication related proteins. The MCM complex consisting of this protein and MCM2, 6 and 7 proteins possesses DNA helicase activity, and may act as a DNA unwinding enzyme. The phosphorylation of this protein by CDC2 kinase reduces the DNA helicase activity and chromatin binding of the MCM complex. This gene is mapped to a region on the chromosome 8 head-to-head next to the PRKDC/DNA-PK, a DNA-activated protein kinase involved in the repair of DNA double-strand breaks. Alternatively spliced trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypogonadism
Hypogonadism means diminished functional activity of the gonads—the testes or the ovaries—that may result in diminished production of sex hormones. Low androgen (e.g., testosterone) levels are referred to as hypoandrogenism and low estrogen (e.g., estradiol) as hypoestrogenism. These are responsible for the observed signs and symptoms in both males and females. Hypogonadism, commonly referred to by the symptom "low testosterone" or "Low T", can also decrease other hormones secreted by the gonads including progesterone, DHEA, anti-Müllerian hormone, activin, and inhibin. Sperm development (spermatogenesis) and release of the egg from the ovaries (ovulation) may be impaired by hypogonadism, which, depending on the degree of severity, may result in partial or complete infertility. In January 2020, the American College of Physicians issued clinical guidelines for testosterone treatment in adult men with age-related low levels of testosterone. The guidelines are supported b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
POLA2
DNA polymerase alpha subunit 2 is an enzyme that in humans is encoded by the ''POLA2'' gene. Interactions POLA2 has been shown to interact with PARP1. See also * DNA Polymerase * DNA polymerase alpha DNA polymerase alpha also known as ''Pol α'' is an enzyme complex found in eukaryotes that is involved in initiation of DNA replication. The DNA polymerase alpha complex consists of 4 subunits: POLA1, POLA2, PRIM1, and PRIM2. Pol α has lim ... References Further reading * * * * * * * * * * External links PDBe-KB provides an overview of all the structure information available in the PDB for Human DNA polymerase alpha subunit B {{gene-11-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
