Search results

The protein kinase A holoenzyme is a heterotetramer composed of two types of subunits: Catalytic and Regulatory. The Catalyticsubunit contains the enzyme's active site. It also contains a domain that binds ATP and a domain that binds the regulatory subunit. The Regulatory subunit consists oftwo molecules which bind one another in an anti-parallel orientation to form a homodimer; for type I subunits- this binding is covalent via disulfide bonds. This subunit also has has two domains that bind cyclic AMP, a domain that interacts with a catalytic subunit, and an "auto-inhibitory" domain that serves as a substrate or pseudosubstrate for the catalytic subunit. Regulatory subunits may also have biologic activity distinct from their role in modulating catalytic subunit activity. Regulatory subunits exist in two major forms, RI and RII, with each form having two subtypes designated alpha and beta. Each of the four isotypes of the regulatory subunit is encoded by a different gene. In addition, three isotypes of the catalytic subunit have been identified (alpha, beta and gamma). The different isotypes tend to have different distributions within cells and among tissues. Type I enzymes inhabit cytoplasmic, soluble fractions of the cell, whereas type II enzymes tend to associate with cellular membranes.

Cholinergic Receptor Nicotinic, Alpha 6 (CHRNA6) is a part of the nicotinic acetylcholine receptors (nAChRs) family. nAChRs are heteropentameric ligand-gated ion channels generating from the assembly of alpha and beta protein subunits. After binding acetylcholine, the AChRs respond by a major change in conformation which affects all subunits and leads to opening of an ion-conducting channel across the plasma membrane. CHRNA6 receptors have a rather selective localization to the nigrostriatal pathway.

CKMT1A is in charge of the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT1A is a member of the creatine kinase isoenzyme family and exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase arises in two different oligomeric forms: dimers and octamers, unlike the exclusively dimeric cytosolic creatine kinase isoenzymes. Numerous malignant cancers with poor prognosis have displayed overexpression of ubiquitous mitochondrial creatine kinase which is linked to high energy turnover and inability to remove cancer cells through apoptosis.

C-type Lectin Domain Family 2, Member B (CLEC2B) belongs to the C-type lectin/C-type lectin-like domain (CTL/CTLD) superfamily. Members of the CTL/CTLD family share a common protein fold and have various functions, such as cell adhesion, cell-cell signaling, glycoprotein turnover, and roles in inflammation and immune response. The CLEC2B gene is closely connected to other CTL/CTLD superfamily members on chromosome 12p13 in the natural killer gene complex region. CLEC2B is expressed preferentially in lymphoid tissues, and in most hematopoietic cell types.

CMC4 is a downstream 8kDa protein restricts to mitochondria which was identified by participation in some t(X;14) translocations related with mature T-cell proliferations. This region has a compound gene structure, with a common promoter and 5’ exon spliced to two different groups of 3’ exons which encode 2 separate proteins.

Cathepsin-Z (CTSZ) is a lysosomal cysteine proteinase and a member of the peptidase C1 family. CTSZ, which is known also as cathepsin X and cathepsin P, exhibits carboxy-monopeptidase and carboxy-dipeptidase activities. CTSZ is expressed ubiquitously in cancer cell lines and primary tumors and as other members of this family, takes part in tumorigenesis.

C-type Lectin Domain Family 1 Member B, also known as CLEC1B. NK-Natural killer cells express multiple calcium-dependent (C-type) lectin-like receptors, for instance CD94 (KLRD1; MIM 602894) and NKG2D (KLRC4; MIM 602893), which interact with major histocompatibility complex class I molecules and either inhibit or else activate cytotoxicity and cytokine secretion. CLEC1B is a C-type lectin-like receptor which is expressed in myeloid cells as well as in NK cells.

C-Src Tyrosine Kinase, also known as CSK, regulates cell growth, migration, differentiation, and immune response. CSK Phosphorylates tyrosine residues located in the C-terminal tails of Src-family kinases. CSK is a protein coding gene which suppresses signaling by several surface receptors. Among CSK's related pathways are PI-3K cascade and Signaling by FGFR.

E-cadherin (uvomorulin, cell-CAM120/80) is a calcium dependent cell adhesion molecule expressed predominately in epithelial tissues. It plays an important role in the growth and development of cells via the mechanisms of control of tissue architecture and the maintenance of tissue integrity. Numerous studies have demonstrated that reduction and/or loss of Ecadherin expression in carcinomas correlates positively with the potential of these tumors for invasion and metastasis.

LCAT is an extracellular cholesterol esterifying enzyme, lecithin-cholesterol acyltransferase. The esterification of cholesterol is required for cholesterol transport. LCAT is a essential enzyme in the extracellular metabolism of plasma lipoproteins.

CST6 belongs to the type 2 cystatin family. Unlike other family members that act as active cysteine protease inhibitors, CST6 restrain the inhibition of cathepsin B but is not active against cathepsin C. CST6 are secretable proteins that influence osteogenesis and bone resorption, regulation of the hepatocyte growth factor receptors, and the response to systemic inflammation.

Cystatin E/M or CST6 is part of the cystatin type 2 family. Part of the cystatin type 2 family members can act as cysteine protease inhibitors, whereas cystatin E/M regulates cathepsin B inhibitors and not cathepsin C. cystatin E/M is a protein the when secreted, has an effect on osteogenesis and bone resorption, insulin regulation, response to systemic inflammation & hepatocyte growth factor receptors.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Cation transport regulator-like protein 2 (CHAC2) is a member of the chaC family. Catalyzes the cleavage glutathione into 5-oxoproline and a Cys-Gly dipeptide. Acts specifically on glutathione, but not on other gamma-glutamyl peptides.

TBCEL, is a factor that is in charge of the microtubule cytoskeleton in determining cell behavior. TBCEL plays a role as a regulator of tubulin stability. While widely expressed in testis, TBCEL is also present in several tissues at a much lower level. TBCEL comprises of seven LRR (leucine-rich) repeats, one LRRCT domain and one ubiquitin-like domain. The gene that translates TBCEL consists of 66,704 bases and maps to human chromosome 11q23.3. Chromosome 11 houses over 1,400 genes and consist of nearly 4% of the human genome. Jervell and Lange-Nielsen syndrome, Jacobsen syndrome, Niemann-Pick disease, hereditary angioedema and Smith-Lemli-Opitz syndrome are associated with defects in genes that map to chromosome 11.

E.Coli Acetate Kinase, also knowns as ACKA, catalyzes the formation of acetyl phosphate from acetate and ATP and also catalyzes the reverse reaction. ACKA takes part in synthesis of various ATP formed catabolically during anaerobic growth of the organism.

CCR4-Not transcription complex, subunit 7 (CNOT7) is a ubiquitous transcription factor. CNOT7 is a component of the CCR4 complex which functions as a general transcription regulation complex. Furthermore, CNOT7 binds to an anti-proliferative protein, BTG1 (B-cell translocation protein 1), which negatively regulates cell proliferation.

ACE-2 (Angiotensin converting enzyme 2) an enzyme bound to cell membranes in various organs such as intestines arteries , lungs, heart & kidney. ACE2 an entry receptor of SARS coronaviruses as well as SARS-CoV-2,.The coronavirus spike (S) glycoprotein is a class I viral fusion antigen located on the external envelope of the virion that takes part in a critical part in viral infection by identifying host cell receptors and facilitating fusion of the viral and cellular membranes. 2 main domains in coronavirus S1 have been recognized, the N-terminal domain and C-terminal domain. One or the other and/or both S1 domains function as a receptor-binding domain. SARS-CoV + MERS-CoV equally use C-domain to attach their receptors.ACE2 is a type I transmembrane antigen with an extracellular N-terminal domain having the catalytic site and an intracellular C-terminal tail. ACE2 obtains a signal peptide, a transmembrane domain, and a single metalloproteinase active site containing an HEXXH zinc-binding domain. ACE-2 plays a role as a mono-carboxypeptidase which degrades Ang I to produce the nonapeptide Ang 1–9 and Ang II to create the heptapeptide Ang 1–7.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and subsequently, the atherosclerosis and abdominal aortic aneurysm.

Cystatin 7 (CST7) is a glycosylated cysteine protease inhibitor with a putative role in immune regulation through inhibition of a unique target in the hematopoietic system. Cystatin-7 is comprised of multiple cystatin-like sequences. The superfamily is comprised of 3 inhibitory families: the type 1 cystatins (stefins), type 2 cystatins and the kininogens. Some members are active cysteine protease inhibitors, while others have lost or possibly never had this inhibitory activity. Type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in various human fluids and secretions. CST7 protein expression has been observed in numerous human cancer cell lines established from malignant tumors.

C-type lectin domain family 5-member A isoform 1 (CLEC5A) is part of the CTL/CTLD superfamily which carry various functions, for instance cell-cell signaling, cell adhesion, glycoprotein turnover, in addition to their inflammation & immune response abilities. CLEC5A operates as a cell attachment receptor for all 4 serotypes of Dengue virus in addition to Japanese encephalitis virus. CLEC5A binds to the dengue virus and it triggers signaling through the phosphylation of TYROBP, as a result no viral entrance occurs, however this interaction does stimulate proinflammatory cytokine release. CLEC5A preforms as a positive regulator of osteoclastogenesis and also a main regulator of synovial injury & bone erosion for the period of autoimmune joint inflammation.

Beta-lactamase is a type of enzyme (EC 3.5.2.6) produced by some bacteria that is responsible for their resistance to beta-lactam antibiotics like penicillins, cephalosporins, cephamycins and carbapenems. These antibiotics have a common element in their molecular structure: a four-atom ring known as a beta-lactam. The lactamase enzyme breaks that ring open, deactivating the molecule's antibacterial properties.

Human Cystatin A (CSTA or Stefin A) belongs to family 1 of the cystatin superfamily, which is characterized by the lack of disulphide bonds and carbohydrates. CSTA is an intracellular inhibitor regulating the activities of cysteine proteases of the papain family such as Cathepsins B, H and L. Cystatin A has also been implicated in several disease states. Because of altered proteolytic state in cancer progression, CSTA may have a role in the proteolitic pathways.