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Spectrin Repeat
Spectrin repeats are found in several proteins involved in cytoskeletal structure. These include spectrin, alpha-actinin, dystrophin and more recently the plakin family. The spectrin repeat forms a three-helix bundle. These conform to the rules of the heptad repeat. Spectrin repeats give rise to linear proteins. This however may be due to sample bias in which linear and rigid structures are more amenable to crystallization. There are hints however, that some proteins harbouring spectrin repeats may also be flexible. This is most likely due to specifically evolved functional purposes. Human proteins containing this domain ACTN1; ACTN2; ACTN3; ACTN4; AKAP6; SYNE3; CATX-15; DMD; DRP2; DST; KALRN; MACF1; MCF2L; SPTA1; SPTAN1; SPTB; SPTBN1; SPTBN2; SPTBN4; SPTBN5; SYNE1; SYNE2; TRIO; UTRN Utrophin is a protein that in humans is encoded by the ''UTRN'' gene. The protein encoded by this gene is a compo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoskeleton
The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is composed of similar proteins in the various organisms. It is composed of three main components, microfilaments, intermediate filaments and microtubules, and these are all capable of rapid growth or disassembly dependent on the cell's requirements. A multitude of functions can be performed by the cytoskeleton. Its primary function is to give the cell its shape and mechanical resistance to deformation, and through association with extracellular connective tissue and other cells it stabilizes entire tissues. The cytoskeleton can also contract, thereby deforming the cell and the cell's environment and allowing cells to migrate. Moreover, it is involved in many cell signaling pathways and in the uptake of extracellular material ( endocytosis), the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KALRN
Kalirin, also known as Huntingtin-associated protein-interacting protein (HAPIP), protein duo (DUO), or serine/threonine-protein kinase with Dbl- and pleckstrin homology domain, is a protein that in humans is encoded by the ''KALRN'' gene. Kalirin was first identified in 1997 as a protein interacting with huntingtin-associated protein 1. Is also known to play an important role in nerve growth and axonal development. Kalirin is a member of the Dbl family of proteins and is a Rho guanine nucleotide exchange factor. It is named after the multiple-handed Hindu goddess Kali for its ability to interact with numerous other proteins. Kalirin's other name, DUO, comes from the fact that it is 98% identical to rat DUO protein and 80.6% identical to a human protein named TRIO. Unlike TRIO, which is expressed in numerous tissues, Kalirin isoforms are mainly found in the brain. Clinical significance Several isoforms of Kalirin are produced through alternative splicing. One of the isoforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UTRN
Utrophin is a protein that in humans is encoded by the ''UTRN'' gene. The protein encoded by this gene is a component of the cytoskeleton. Utrophin was found during research into Duchenne's muscular dystrophy. The name is a contraction for ''ubiquitous dystrophin''. The 900 kb gene for utrophin is found on the long arm of human chromosome 6. Utrophin was discovered due to its homology with dystrophin. It was found by screening a peptide containing the C-terminal domain of dystrophin against cDNA libraries. The homology varies over its full length from less than 30% in regions of the central rod structural domain to 85% (identity 73%) for the actin binding domain. The tertiary structure of utrophin contains a C-terminus that consists of protein–protein interaction motifs that interact with dystroglycan, a central rod region consisting of a triple coiled-coil repeat, and an actin-binding N-terminus. In normal muscle cells, utrophin is located at the neuromuscular synapse a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SYNE2
Nesprin-2 is a protein that in humans is encoded by the ''SYNE2'' gene. The human SYNE2 gene consists of 116 exons and encodes nesprin-2, a member of the nuclear envelope (NE) spectrin-repeat (nesprin) family. Nesprins are modular proteins with a central extended spectrin-repeat (SR) rod domain and a C-terminal Klarsicht/ANC-1/Syne homology (KASH) transmembrane domain, which acts as a NE-targeting motif. Nesprin-2 (Nesp2) binds to cytoplasmic F-actin, tethering the nucleus to the cytoskeleton The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is compos ... and maintaining the structural integrity of the nucleus. The human SYNE2 gene encodes a protein of 6,885 amino acids (isoform 1, Nesp2 giant); alternative mRNA splicing produces transcripts encoding a larger isoform and numerous smaller isoforms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SYNE1
Enaptin also known as nesprin-1 or synaptic nuclear envelope protein 1 (syne-1) is an actin-binding protein that in humans that is encoded by the SYNE1 gene. Function This gene encodes a spectrin repeat containing protein expressed in skeletal and smooth muscle, and peripheral blood lymphocytes, that localizes to the nuclear membrane. Enaptin is a nuclear envelope protein found in human myocytes and synapses, which is made up of 8,797 amino acids. Enaptin is involved in the maintenance of nuclear organization and structural integrity, tethering the cell nucleus to the cytoskeleton by interacting with the nuclear envelope and with F-actin in the cytoplasm. Structure Enaptin contains a coiled alpha-helical region and a large beta-sheet region in the upper part and at least four alpha-helices spliced together, indicating the similarity with collagen. The protein is made up of three main parts, as can be seen in the diagram: cytoplasmic (1-8746), anchor for type IV membrane pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTBN5
Spectrin, beta, non-erythrocytic 5 also known as SPTBN5 is a protein that in humans is encoded by the ''SPTBN5'' gene. SPTBN5 belongs to the spectrin family of cytoskeletal proteins. Structure and function SPTBN5 contains the following domains: * actin-binding domain * membrane-association domain-1 * self-association domain * C-terminal pleckstrin homology domain Pleckstrin homology domain (PH domain) or (PHIP) is a protein domain of approximately 120 amino acids that occurs in a wide range of proteins involved in intracellular signaling or as constituents of the cytoskeleton. This domain can bind phospha .... Based on these structural features it is thought that SPTBN5 is likely to form heterodimers and oligomers with alpha-spectrin and to interact directly with cellular membranes. SPTBN5 is highly expressed in embryoid bodies. References Further reading * * * * {{gene-15-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTBN4
Spectrin, beta, non-erythrocytic 4, also known as SPTBN4, is a protein that in humans is encoded by the ''SPTBN4'' gene. Spectrin is an actin crosslinking and molecular scaffold protein that links the cell membrane to the actin cytoskeleton, and functions in the determination of cell shape, arrangement of transmembrane proteins, and organization of organelles. It is composed of two antiparallel dimers of alpha- and beta- subunits. This gene is one member of a family of beta-spectrin genes. The encoded protein localizes to the nuclear matrix, PML nuclear bodies, and cytoplasmic vesicles. A highly similar gene in the mouse is required for localization of specific membrane proteins in polarized regions of neurons. Multiple transcript variants encoding different isoforms have been found for this gene. Interactions SPTBN4 has been shown to interact with PTPRN and DISC1 Disrupted in schizophrenia 1 is a protein that in humans is encoded by the ''DISC1'' gene. In coordination with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTBN2
Spectrin beta chain, brain 2 is a protein that in humans is encoded by the ''SPTBN2'' gene. Clinical significance Mutations in this gene is associated with Spinocerebellar ataxia type 5. Interactions SPTBN2 has been shown to interact with: * ACTR1A, * Beta-actin, and * UNC13B Protein unc-13 homolog B is a protein that in humans is encoded by the ''UNC13B'' gene. Function This gene is expressed in the kidney cortical epithelial cells and is upregulated by hyperglycemia. The encoded protein shares a high level of sim .... References Further reading * * * * * * * * * * {{Gene-11-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTBN1
Spectrin beta chain, brain 1 is a protein that in humans is encoded by the ''SPTBN1'' gene. Function Spectrin is an actin crosslinking and molecular scaffold protein that links the plasma membrane to the actin cytoskeleton, and functions in the determination of cell shape, arrangement of transmembrane proteins, and organization of organelles. It is composed of two antiparallel dimers of alpha- and beta- subunits. This gene is one member of a family of beta-spectrin genes. The encoded protein contains an N-terminal actin-binding domain, and 17 spectrin repeats that are involved in dimer formation. Multiple transcript variants encoding different isoforms have been found for this gene. Interactions SPTBN1 has been shown to Protein-protein interaction, interact with Merlin (protein), Merlin. Model organisms Model organisms have been used in the study of spectrin function. A conditional knockout mouse line, called ''Spnb2tm1a(EUCOMM)Wtsi'' was generated as part of the Internationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTB
Spectrin beta chain, erythrocyte is a protein that in humans is encoded by the ''SPTB'' 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-14-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SPTAN1
Alpha II-spectrin, also known as Spectrin alpha chain, brain is a protein that in humans is encoded by the ''SPTAN1'' gene. Alpha II-spectrin is expressed in a variety of tissues, and is highly expressed in cardiac muscle at Z-disc structures, costameres and at the sarcolemma membrane. Mutations in alpha II-spectrin have been associated with early infantile epileptic encephalopathy-5, and alpha II-spectrin may be a valuable biomarker for Guillain–Barré syndrome and infantile congenital heart disease. Structure Alternate splicing of alpha II-spectrin has been documented and results in multiple transcript variants; specifically, cardiomyocytes have four identified alpha II-spectrin splice variants. As opposed to alpha I-spectrin that is principally found in erythrocytes, alpha II-spectrin is expressed in most tissues. In cardiac tissue, alpha II-spectrin is found in myocytes at Z-discs, costameres, and the sarcolemma membrane, and in cardiac fibroblasts along the surface of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
