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Ostreolysin is extracted from Pleurotus ostreatus (oyster mushroom). It is a pore forming protein, which contains a lytic part to both cholesterol and sphingomyelin containing membranes. Because of their cholesterol content and the appearance of ostreolysin in the detergent resistant membranes, ostreolysin is cytotoxic towards the ovary cells of Chinese hamster. It seems that Ostreolysin spots a rich lipid cholesterol phase, presumably the liquid ordered phase.

KIT, also known as KIT Proto-Oncogene Receptor Tyrosine, is a cytokine receptor which is expressed not only in hematopoietic stem cells but likewise in other cell types. KIT binds to receptor tyrosine kinase type III, which is a stem cell factor, also named a "rigid factor" or "c-kit ligand". Once this receptor binds to stem cell factor (SCF), it forms a dimer which activates intrinsic tyrosine kinase activity, which sequentially phosphorylates & activates signaling molecules which breed signals in cells. This receptor protects vascular smooth muscle cells from apoptosis in addition to restoring cardiac function after myocardial infarction.

The protein encoded by LAMP2 belongs to a family of membrane glycoproteins. This glycoprotein provides selectins with carbohydrate ligands LAMP2 takes part in tumor cell metastasis and in addition has a role in the protection, maintenance, and adhesion of the lysosome. The effect of alternative splicing of this gene is multiple transcript variants encoding distinct proteins.

Matrix metalloproteinase-7 (MMP-7) also known as matrilysin and PUMP (EC 3.4.24.23) cleaves a number of substrates including collagen types IV and X, elastin, fibronectin, gelatin, laminin and proteoglycans. MMP-7 is closely related to the stromelysin family members but is encoded by a different gene. MMP-7 is the smallest of all the MMPs consisting of a pro-peptide domain and a catalytic domain. It lacks the hemopexin-like domain common to other members of the MMPs. MMP-7 is secreted as a 28 kDa proenzyme and can be activated in vitro by organomercurials and trypsin and in vivo by MMP-3 to a 18 kDa active MMP-7 enzyme. Once activated, MMP-7 can activate pro-MMP-1 and pro-MMP-9 but not pro-MMP-2. MMP-7 is widely expressed having been reported in elevated levels in cycling endometrium as well as in colorectal cancers and adenomas, hepatocellular carcinomas, rectal carcinomas, and approximately 50% of gliomas.

TIMP1 is a member of the TIMP family. TIMP1 is an inducible glycoprotein produced by various cell types. The TIMP1 glycoprotein is a natural inhibitor of the matrix metalloproteinases, which a group of peptidases involved in degradation of the extracellular matrix. TIMP1 binds in a reversible mode to MMPs, with regions in the N-terminal domain binding to the MMP substrate-binding site. On top of its inhibitory function against most of the known MMPs, TIMP1 is able to promote cell proliferation in a broad range of cell types, and may also have an anti-apoptotic role. Furthermore, TIMP1 has erthyroid-potentiating activity via translocation to the nucleus and also inhibits apoptosis in B-cells. The TIMP1 gene is situated within intron 6 of the synapsin I gene and is transcribed in the opposite direction. TIMP1 activity is dependent on the existence of disulfide bonds. TIMP1 transcription is extremely inducible in reaction to many cytokines and hormones.
Increased TIMP1 levels are connected with squamous cell laryngeal carcinoma. TIMP1 overexpression is linked to gastric cancer.

TPMT, thiopurine S-methyltransferase, is a cytosolic enzyme that metabolizes thiopurine drugs via S-adenosyl-L-methionine as the S-methyl donor and S-adenosyl-L-homocysteine as a byproduct. TPMT activity exhibits autosomal codominant genetic polymorphism, and patients inheriting TPMT-deficiency are at high risk of potentially fatal hematopoietic toxicity.

Lipopolysaccharide-induced TNF-alpha factor (LITAF) is a small integral membrane protein of lysosome/late endosome. The expression of inflammatory cytokines such as TNF-alpha in Lipopolysaccharide-induced processes is mediated by LITAF. LITAF connects to STAT6B, which belongs to the STAT6 family forming a complex on the TNF-alpha promoter that modifies TNF activity. High levels of expression of LITAF mRNA are observed mostly in the placenta, peripheral blood leukocytes, lymph nodes and spleen.

Recoverin is a member of the recoverin family of neuronal calcium sensors. Recoverin is a heterogeneously acylated calcium-binding and intracellular signal transduction 23kDa protein in the photoreceptor cells of retina. Recoverin contains four EF-hands, of which two bind Ca. Ca-induced extrusion of the acyl group from a hydrophobic cleft in the protein drives the translocation of recoverin from solution to the disc membrane. Recoverin may prolong the termination of the phototransduction cascade in the retina by blocking the phosphorylation of photo-activated rhodopsin. Recoverin plays a key role in the inhibition of rhodopsin kinase, a molecule that regulates the phosphorylation of rhodopsin. This in due course controls the ability of the eye to adapt to, and recover from, exposure to the presence of light. Recoverin is a detectable serologic protein that is expressed in patients with cancer-associated retinopathy, a paraneoplastic syndrome.

40S ribosomal protein S18 (RPS18) is a member of the ribosomal protein S13P family.RPS18 is located in the cytoplasm. Ribosomes, the organelles which catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit.Jointly these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. RPS18 encodes a ribosomal protein which is a component of the 40S subunit. RPS18 is a recognized binding partner of Cofilin and has been proposed to be a novel substrate for CaMKII. Among the diseases associated with RPS18 are bowen-conradi syndrome, and pasteurellosis.

Serine protease 28, also known as Prss28, is a member of the S1 serine proteinase family with a conserved Histidine-Aspartic Acid-Serine catalytic triad. Prss28 shows mixed substrate specificity which silences signaling through proteinase-activated receptors. Furthermore, Prss28 is involved with embryo hatching and its activity is vital for successful implantation.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

lysozyme G-like 2 and LYGH (LYG2), is a member of the glycosyl hydrolase 23 family. Lysozyme takes part in human innate immunity by causing bacterial cell lysis. LYG2 contains a SLT domain, a protein domain present in bacterial lytic transglycosylase (SLT) and in eukaryotic lysozymes (GEWL). SLT domain catalyzes the cleavage of the beta-1,4-glycosidic bond between N-acetylmuramic acid (MurNAc) and N-acetyglucosamine (GlcNAc).

TPM1 is a member of the tropomyosin family which consists of a number of extremely conserved, extensively distributed 35-45 kDa actin-binding proteins that are involved in the contractile system of striated and smooth muscles and the cytoskeleton of non-muscle cells. Tropomyosin-1 is composed of 2 alpha-helical chains arranged as a coiled-coil. TPM1 is polymerized end to end alongside the two grooves of actin filaments and provides stability to the filaments. TPM1 binds to actin filaments in muscle and non-muscle cells. TPM1 also functions in association with the troponin complex to regulate the calcium-dependent interaction of actin and myosin during muscle contraction. In non-muscle cells TPM1 is implicated in stabilizing cytoskeleton actin filaments. Smooth muscle contraction is controlled by interaction with caldesmon.
Alternatively spliced transcript variants encoding a range of isoforms have been described in smooth muscle and non-muscle cells. TPM1 Isoform 1 is expressed in adult and fetal skeletal muscle and cardiac tissues, with higher expression levels in the cardiac tissues, whereas Isoform 10 is expressed in adult and fetal cardiac tissues, but not in skeletal muscle.
Mutations in the TPM1 gene are linked to type 3 familial hypertrophic cardiomyopathy.

PRRX1 is part of the paired family of homeobox proteins. PRRX1 functions as a transcription co-activator, enhancing the DNA-binding activity of serum response factor, a protein required for the induction of genes by growth and differentiation factors. PRRX1 also regulates muscle creatine kinase, and therefore has a part in the establishment of diverse mesodermal muscle types. The protein binds to an A/T-rich element in the muscle creatine enhancer. Among the diseases associated with PRRX1 are agnathia-otocephaly complex, and pleomorphic liposarcoma.

Crystallin, Mu (CRYM) is a taxon-specific crystallin protein which binds NADPH and has sequence similarity to bacterial ornithine cyclodeaminases. CRYM doesn’t perform a structural role in lens tissue; instead CRYM binds thyroid hormone for possible regulatory or developmental roles. CRYM gene mutations are linked with autosomal dominant non-syndromic deafness. CRYM specifically catalyzes the reduction of imine bonds in brain substrates which may include cystathionine ketamine and lanthionine ketamine.

Modulator of apoptosis 1 (MOAP1), is a member of the PNMA family and contains one BH3-like domain and one RASSF1-binding domain. MOAP1 was recognized by its interaction with apoptosis regulator BAX protein. MOAP1 includes a Bcl-2 homology 3 (BH3)-like motif, which is essential for the association with BAX. In addition, once over expressed MOAP1 mediates caspase-dependent apoptosis.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

Zinc Finger Protein 689 (ZNF689) is a member of the krueppel C2H2-type zinc-finger protein family. The ZNF689 protein contains 12 C2H2-type zinc fingers and 1 KRAB domain. ZNF689 may be involved in transcriptional regulation.

The conserved 76 amino acid protein ubiquitin (Ub) regulates a host of intracellular processes through its enzymatic conjugation to other cellular proteins.
Ubiquitination occurs through sequential steps catalyzed by activating (E1), conjugating (E2), and ligase (E3) enzymes. The final step results in the formation of an isopeptide bond between Ub’s C-terminal glycine residue (G76) and a lysine residue of the target protein, although N-terminal ubiquitination is also known.
Outcomes of this modification include destabilization of the conjugated protein, altered protein trafficking and functional modulation.
After targeting the protein for specific localizations, ubiquitin is released from the substrate by deubiquitinating enzymes.
A mutant ubiquitin, having a Gly to Ala substitution at the C-terminus (G76A ubiquitin) supported several downstream reactions of the proteolytic pathway but inhibits the deubiquitination process.
As consequence, the Ub derivative becomes irreversibly conjugated to protein, shifting the equilibrium between the bound and unbound form in the direction of conjugation, at the expense of the free form.

Procollagen C-endopeptidase enhancer 1, also known as PCOLCE binds to the C-terminal propeptide of type I procollagen and enhances procollagen C-proteinase activity. In addition, C-terminal processed part of PCPE (CT-PCPE) has a metalloproteinase inhibitory activity. Among the diseases which are associated with PCOLCE: bone fracture & oculopharyngeal muscular dystrophy.

Phospholipid scramblase (PLSCR1) is a member of the phospholipid scramblase family. PLSCR1 has a significant part in the antiviral reaction of IFN by intensifying and improving the IFN reaction via increasing expression of select subset of potent antiviral genes. PLSCR1 promotes cytokine-regulated cell proliferation and differentiation.

ABRACL is a member of the costars family, ABRACL belongs to a new family of low molecularweight proteins, which is presented only in eukaryotes, and is absent in fungi.ABRA C-terminal like is a protein-coding gene.