|
DNA Polymerase Alpha Catalytic Subunit
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 addition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), 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, 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 include Ribozyme, catalytic RNA molecules, also called ribozymes. They are sometimes descr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypogonadism
Hypogonadism means diminished functional activity of the human gonad, gonads—the testicles or the ovary, ovaries—that may result in diminished biosynthesis, 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, dehydroepiandrosterone, DHEA, anti-Müllerian hormone, activin, and inhibin. Spermatogenesis, Sperm development (spermatogenesis) and ovulation, 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 (medication), ... [...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] |
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: * Helico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinoblastoma Protein
Retinoblastoma (Rb) is a rare form of cancer that rapidly develops from the immature cells of a retina, the light-detecting tissue of the eye. It is the most common primary malignant intraocular cancer in children, and 80% of retinoblastoma cases are first detected in those under 3 years old. Though most children in high income countries survive this cancer, they may lose their vision in the affected eye(s) or need to have the eye removed. Almost half of children with retinoblastoma have a hereditary genetic defect associated with it. In other cases, retinoblastoma is caused by a congenital mutation in the chromosome 13 gene 13q14 ( retinoblastoma protein). Signs and symptoms Retinoblastoma is the most intrusive intraocular cancer among children. The chance of survival and preservation of the eye depends fully on the severity. Retinoblastoma is extremely rare as there are only about 200 to 300 cases every year in the United States. Globally, only 1 in about 15,000 childre ... [...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. See also * GINS (protein complex) GINS is a protein complex essential to the DNA replication process in the cells of eukaryotes. The complex participates in the initiation and elongation stages of replication. The name GINS is an acronym created from the first letters of the Japan ... * Eukaryotic DNA replication#GINS Explains role of GINS during DNA replication in eukaryotic cells. 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 A pre-replication complex (pre-RC) is a protein complex that forms at the origin of replication during the initiation step of DNA replication. Formation of the pre-RC is required for DNA replication to occur. Complete and faithful replication of ... (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 helicas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcephaly
Microcephaly (from Neo-Latin ''microcephalia'', from Ancient Greek μικρός ''mikrós'' "small" and κεφαλή ''kephalé'' "head") is a medical condition involving a smaller-than-normal head. Microcephaly may be present at birth or it may develop in the first few years of life. Brain development is often affected; people with this disorder often have an intellectual disability, poor motor function, poor speech, abnormal facial features, seizures and dwarfism. The disorder is caused by a disruption to the genetic processes that form the brain early in pregnancy, though the cause is not identified in most cases. Many genetic syndromes can result in microcephaly, including chromosomal and single-gene conditions, though almost always in combination with other symptoms. Mutations that result solely in microcephaly (primary microcephaly) exist but are less common. External toxins to the embryo, such as alcohol during pregnancy or vertically transmitted infections, can a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. 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 non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-linked Reticulate Pigmentary Disorder
X-linked reticulate pigmentary disorder is a rare Sex linkage, X-linked genetic condition in which Male, males manifest multiple systemic Signs and symptoms, symptoms and a reticulated mottled brown Pigment, pigmentation of the skin, which, on biopsy, demonstrated Dermis, dermal deposits of amyloid. Female, Females usually only have linear streaks of hyperpigmentation. The syndrome can also be referred to by the acronym X-Linked-PDR or XLPRD. Its a very rare X-linked recessive inheritance, recessive disease, genetically determined, with a chronic course. It was characterized in 1981. Mutation of the ''DNA polymerase alpha catalytic subunit, POLA1'' gene lead to loss of expression of the catalytic subunit of DNA polymerase alpha, DNA polymerase-α and is responsible for XLPDR. Loss of POLA1 expression resulted in reduced levels of RNA:DNA hybrids in the cytosol and unexpectedly triggered aberrant Immune response, immune responses (e.g. Interferon type I, type I interferon product ... [...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 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 t ... * DNA polymerase alpha 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] |
