KNL1
KNL1 (kinetochore scaffold 1, aka CASC5) is a protein that is encoded by the ''KNL1'' gene in humans. Function KNL1 is part of the outer kinetochore. It is a part of KMN network of proteins together with MIS12, and NDC80. KNL1 is involved in microtubule attachment to chromosome centromeres and in the activation of the spindle checkpoint during mitosis. The ''CASC5'' gene is upregulated in the areas of cell proliferation surrounding the ventricles during fetal brain development. Interactions CASC5 has been shown to interact with MIS12, BUB1, BUBR1 and ZWINT-1. Polymorphisms Homozygous polymorphisms in the ''CASC5'' gene have been seen in patients with autosomal recessive primary microcephaly (MCPH). The mutation resulted in the skipping of exon 18 transcription, causing a frameshift Ribosomal frameshifting, also known as translational frameshifting or translational recoding, is a biological phenomenon that occurs during translation that results in the production of multip ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Microcephaly
Microcephaly (from New 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. Since brain growth is correlated with head growth, 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 infec ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called peptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residue ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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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]   |
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Kinetochore
A kinetochore (, ) is a disc-shaped protein structure associated with duplicated chromatids in eukaryotic cells where the spindle fibers attach during cell division to pull sister chromatids apart. The kinetochore assembles on the centromere and links the chromosome to microtubule polymers from the mitotic spindle during mitosis and meiosis. The term kinetochore was first used in a footnote in a 1934 Cytology book by Lester W. Sharp and commonly accepted in 1936. Sharp's footnote reads: "The convenient term ''kinetochore'' (= movement place) has been suggested to the author by J. A. Moore", likely referring to John Alexander Moore who had joined Columbia University as a freshman in 1932. Monocentric organisms, including vertebrates, fungi, and most plants, have a single centromeric region on each chromosome which assembles a single, localized kinetochore. Holocentric organisms, such as nematodes and some plants, assemble a kinetochore along the entire length of a chromosome. Ki ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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MIS12
Protein MIS12 homolog is a protein that in humans is encoded by the ''MIS12'' gene. Interactions MIS12 has been shown to interact with NSL1, ZWINT, CASC5, Polyamine-modulated factor 1, NDC80, DSN1 DSN1, MIND kinetochore complex component, homolog (S. cerevisiae), also known as DSN1 or MIS13, is a protein which in humans encoded by the ''DSN1'' gene. Function DSN1 along with MIS12, DC8, PMF1, CBX5, ZWINT is a component of the kinetochore- ... and CBX5. References Further reading * * * * * * * * * {{Gene-17-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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NDC80
Kinetochore protein NDC80 homolog is a protein that in humans is encoded by the ''NDC80'' gene. Function Ndc80 is one of the proteins of outer kinetochore. It forms a heterotetramer with proteins NUF2, SPC25, and SPC24. This protein complex has microtubule-binding domains. HEC is one of several proteins involved in spindle checkpoint signaling. This surveillance mechanism assures correct segregation of chromosomes during cell division by detecting unaligned chromosomes and causing prometaphase arrest until the proper bipolar attachment of chromosomes is achieved. Interactions NDC80 has been shown to interact with MIS12, NEK2 and PSMC2 26S protease regulatory subunit 7, also known as 26S proteasome AAA-ATPase subunit Rpt1, is an enzyme that in humans is encoded by the ''PSMC2'' gene This protein is one of the 19 essential subunits of a complete assembled 19S proteasome complex. .... References Further reading * * * * * * * * * * * * * * * * {{PD ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Microtubule
Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 and 15 nm. They are formed by the polymerization of a dimer of two globular proteins, alpha and beta tubulin into protofilaments that can then associate laterally to form a hollow tube, the microtubule. The most common form of a microtubule consists of 13 protofilaments in the tubular arrangement. Microtubules play an important role in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organell ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Spindle Checkpoint
The spindle checkpoint, also known as the metaphase-to-anaphase transition, the spindle assembly checkpoint (SAC), the metaphase checkpoint, or the mitotic checkpoint, is a cell cycle checkpoint during mitosis or meiosis that prevents the separation of the duplicated chromosomes (anaphase) until each chromosome is properly attached to the spindle. To achieve proper segregation, the two kinetochores on the sister chromatids must be attached to opposite spindle poles (bipolar orientation). Only this pattern of attachment will ensure that each daughter cell receives one copy of the chromosome. The defining biochemical feature of this checkpoint is the stimulation of the anaphase-promoting complex by M-phase cyclin-CDK complexes, which in turn causes the proteolytic destruction of cyclins and proteins that hold the sister chromatids together. Overview and importance The beginning of metaphase is characterized by the connection of the microtubules to the kinetochores of the chrom ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Upregulated
In the biological context of organisms' production of gene products, downregulation is the process by which a cell decreases the quantity of a cellular component, such as RNA or protein, in response to an external stimulus. The complementary process that involves increases of such components is called upregulation. An example of downregulation is the cellular decrease in the expression of a specific receptor in response to its increased activation by a molecule, such as a hormone or neurotransmitter, which reduces the cell's sensitivity to the molecule. This is an example of a locally acting (negative feedback) mechanism. An example of upregulation is the response of liver cells exposed to such xenobiotic molecules as dioxin. In this situation, the cells increase their production of cytochrome P450 enzymes, which in turn increases degradation of these dioxin molecules. Downregulation or upregulation of an RNA or protein may also arise by an epigenetic alteration. Such an epigene ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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BUB1
Mitotic checkpoint serine/threonine-protein kinase BUB1 also known as BUB1 (budding uninhibited by benzimidazoles 1) is an enzyme that in humans is encoded by the ''BUB1'' gene. Bub1 is a serine/threonine protein kinase first identified in genetic screens of ''Saccharomyces cerevisiae''. The protein is bound to kinetochores and plays a key role in the establishment of the mitotic spindle checkpoint and chromosome congression. The mitotic checkpoint kinase is evolutionarily conserved in organisms as diverse as ''Saccharomyces cerevisiae'' and humans. Loss-of-function mutations or absence of Bub1 has been reported to result in aneuploidy, chromosomal instability ( CIN) and premature senescence. Structure Bub1p comprises a conserved N-terminal region, a central non-conserved region and a C-terminal serine/threonine kinase domain. The N-terminal region mediates binding of Hs-BUB1 to the mitotic kinetochore protein blinkin (a protein also commonly referred to as AF15q14). The latte ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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ZWINT
ZW10 interactor (Zwint-1) is a protein that in humans is encoded by the ''ZWINT'' gene. Function Zwint-1 is clearly involved in kinetochore function although an exact role is not known. It interacts with ZW10, another kinetochore protein, possibly regulating the association between ZW10 and kinetochores. The encoded protein localizes to prophase kinetochores before ZW10 does and it remains detectable on the kinetochore until late anaphase. It has a uniform distribution in the cytoplasm of interphase cells. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. Interactions ZWINT has been shown to interact with MIS12. ZWINT has also been shown to interact with RAB3C Ras-related protein Rab-3C is a protein that in humans is encoded by the ''RAB3C'' gene. Interactions Rab3C has been shown to interact with ZWINT ZW10 interactor (Zwint-1) is a protein that in humans is encoded by the ''ZWINT'' gene. Funct ... References ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |