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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, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. 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.

Crystallins are the main structural proteins of the vertebrate eye lens, where they maintain the transparency and refractive index of the lens. Crystallins are divided into 3 fprotein families, α, β, & γ families. Because lens central fiber cells lose their nuclei during development, these crystallins are prepared and then retained throughout life, making them extremely stable proteins. CRYBB1 is a beta basic group member and undergoes extensive cleavage at its N-terminal extension during lens maturation.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

CCL15, a new human CC chemokine, was isolated from a human fetal spleen cDNA library. CCL15 cDNA encodes a predicted 113 amino acid (aa) protein containing a putative signal peptide of 21 amino acids that is cleaved to generate a 92 aa residue mature protein. Within the CC family members, human CCL15 shares 45%, 44%, 35%, and 30% aa homology with mouse C10, human MPIF-1, human HCC-1, and mouse MIP-1?, respectively. The gene for MIP-5 is found on chromosome 17 where the genes for most of the human CC chemokines are located. Human CCL15 is expressed in T and B lymphocytes, NK cells, monocytes and monocyte-derived dendritic cells. Human MIP-5 is chemotactic for T cells and monocytes and has been shown to induce calcium flux in human CCR-1-transfected cells.

Human Ubc9 is homologous to ubiquitin-conjugating enzymes (E2s). However, instead of conjugating ubiquitin, it conjugates a ubiquitin homologue, small ubiquitin-like modifier 1(SUMO-1). And hUbc9 retains striking structural and functional conservation with yeast Ubc9. The ubiquitin-dependent protein degradation system has been recognized as a complete enzymatic pathway that is responsible for the selective degradation of abnormal and short-lived proteins. The conjugation of ubiquitin requires the activities of ubiquitin-activating (E1) and –conjugating (E2) enzymes.

FLT3 ligand is a receptor for the fl cytokine has a tyrosine-protein kinase activity & a growth factor that regulates proliferation of early hematopoietic cells. Flt3-Ligand synergizes with other CSFs and interleukins to induce growth and differentiation.

Complement Factor Properdin (CFP) which is a plasma glycoprotein, is a positive regulator of the alternative complement pathway of the innate immune system. CFP binds and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that eventually ends with formation of the membrane attack complex and lysis of the target cell. Mutations in CFP lead to 2 forms of properdin deficiency that cause high susceptibility to meningococcal infections.

Inhibitor of Growth Family, Member 2 (ING2) belongs to the inhibitor of growth (ING) family. ING family members associate with and modulate the activity of histone acetyltransferase (HAT) and histone deacetylase (HDAC) complexes and serve in DNA repair and apoptosis. ING2 appears to be involved in p53/TP53 activation and p53/TP53-dependent apoptotic pathways, most likely by enhancing acetylation of p53/TP53. ING2 is a component of an mSin3A-like corepressor complex, which is probably involved in deacetylation of nucleosomal histones. ING2 activity is modulated by binding to phosphoinositides (PtdInsPs).

Recombinant Fatty Acid Binding Protein is a newly introduced plasma marker of acute myocardial infarction (AMI). The plasma kinetics of FABP (15kD) closely resemble those of myoglobin in that elevated plasma concentrations are found within 2 hours after AMI and return to normal generally within 18 to 24 hours. But the concentration of FABP in the skeletal muscle is 20 times lower than in cardiac tissue (for myoglobin the same content for cardiac and skeletal tissue), that makes FABP to be more cardiac specific than myoglobin. This makes FABP a useful biochemical marker for the early assessment or exclusion of AMI. FABP also appears to be a useful plasma marker for the estimation of myocardial infarct size.

Apoptosis-Inducing Factor, Mitochondrion-Associated, 1 (AIFM1) is a mitochondrial protein which translocates to the nucleus once apoptosis has been initiated. AIFM1 causes DNA fragmentation and chromatin condensation and also triggers the release of cytochrome c and caspase-9 from mitochondria. Bcl-2 overexpression prevents the release of AIFM1 from mitochondria, but doesn’t block its apoptogenic activity.

CYR61 is a growth factor-inducible, immediate-early gene that has multifaceted activities in various cancers. CYR61 is a secreted, cysteine-rich, binding protein which is encoded by a growth factor-inducible immediate-early gene. Acting as an extracellular, matrix-associated signaling molecule, CYR61 promotes the adhesion of endothelial cells through interaction with integrin and enhances growth factor-induced DNA synthesis in the same cell type.

FAD-linked sulfhydryl oxidase ALR (GFER) is a member of the Erv1/ALR family of proteins, which is found in higher and lower eukaryotes. GFER is a hepatotrophic growth factor and flavin-linked sulfhydryl oxidase expressed in a variety of tissues. Moreover, GFER induces the expression of S-adenosylmethionine decarboxyl-ase and ornithine decarboxylases (ODC), which each have a central role in the synthesis of polyamines. The hepatotrophic factor designated augmenter of liver regeneration (ALR) is assumed to be one of the factors responsible for the exceptional regenerative capacity of mammalian liver. The GFER gene is located on chromosome 16 in the interval containing the locus for polycystic kidney disease (PKD1).

Ectonucleoside Triphosphate Diphosphohydrolase 3, also known as ENTPD3, which owns a threefold preference for the hydrolysis of ATP over ADP is similar to E-type nucleotidases (NTPases). ENTPD3 is a protein coding gene which contains four apyrase-conserved areas which is characteristic of NTPases.

PPP1R14A is a phosphorylation-dependent inhibitor of smooth muscle myosin phosphatase. Inhibition of PPP1R14A results to increased myosin phosphorylation and enhances smooth muscle contraction in the absence of increased intracellular Ca(2+) concentration. Myosin phosphatase can reverse MYL (myosin light chain) phosphorylation to induce a state of relaxation. However, during agonist-induced contraction at constant Ca2+ concurrent inhibition of myosin phosphatase leads to increases in MYL phosphorylation and tension. These calcium-independent increases in myosin phosphorylation and tension are termed calcium sensitization. Human pregnancy is characterized by the increases of PKN1 expression and CPI-17 phosphorylation in the myometrium. PPP1R14A is mapped to chromosome 19q13.13-q13.2. PPP1R14A binds directly to protein kinase C and casein kinase I. PPP1R14A siRNA decreased the level of merlin phosphorylation and consequently Ras and ERK activity in human tumor cell lines. PKC/CPI-17 medi

The heat-shock response is elicited by exposure of cells to thermal and chemical stress and through the activation of HSFs (heat shock factors) results in the elevated expression of heat-shock induced genes. Heat shock factor binding protein-1 (HSBP1), is a 76-amino-acid protein that binds to heat shock factor 1(HSF1), which is a transcription factor involved in the HS response. During HS response, HSF1 undergoes conformational transition from an inert non-DNA-binding monomer to active functional trimers. HSBP1 is nuclear-localized and interacts with the active trimeric state of HSF1 to negatively regulate HSF1 DNA-binding activity. Overexpression of HSBP1 in mammalian cells represses the transactivation activity of HSF1. When overexpressed in C.elegans HSBP1 has severe effects on survival of the animals after thermal and chemical stress consistent with a role of HSBP1 as a negative regulator of heat shock response.

Simian immunodeficiency virus, SIV, is a retrovirusthat is found in strains, having the HIV-1and HIV-2specific strains that infect humans. SIV strains may cause an AIDS-like immune deficiency known as SAIDS (simian acquired immunodeficiency syndrome) if they cross species boundaries. HIV-2 is more similar to SIV strains than to HIV-1, suggesting for the first time the simian origin of HIV. HIV-2 is derived from the SIV strain found in sooty mangabeys whereas HIV-1, the predominant virus found in humans, is derived from SIV strains infecting chimpanzees.

TNF-related apoptosis-inducing ligand (TRAIL) is a ligand molecule which induces apoptosis. It is a type II transmembrane protein with homology to other members of the tumor necrosis factor family.
In humans, the gene that encodes for TRAIL is located at chromosome 3q26.
TRAIL binds to the death receptors, DR4 and DR5. The process of apoptosis is caspase-8-dependent. This protein preferentially induces apoptosis in transformed and tumor cells, but does not appear to kill normal cells although it is expressed at a significant level in most normal tissues.

Alanine transaminase or ALT is a transaminaseenzyme.
ALT is found in serumand in various bodily tissues, but is most commonly associated with the liver; It catalyzes the transfer of an aminogroup from alanineto a-ketoglutarate, the products of this reversible transaminationreaction being pyruvateand glutamatealanine+ a-ketoglutarate= pyruvate+ glutamate
It is commonly measured clinically as a part of a diagnostic liver function test, to determine liver health. It is also called serum glutamate pyruvate transaminase (SGPT) or alanine aminotransferase (ALAT). Diagnostically, it is almost always measured in units/litre (U/L).

TDP1 belongs to the phospholipase D family and contains two PLD phosphodiesterase domains. TDP1 is involved in repairing stalled topoisomerase I-DNA complexes by catalyzing the hydrolysis of the phosphodiester bond between the tyrosine residue of topoisomerase I and the 3-prime phosphate of DNA. TDP1 may also remove glycolate from single-stranded DNA containing 3-prime phosphoglycolate, suggesting a role in repair of free-radical mediated DNA double-strand breaks. Mutations in the TDP1 gene are linked to the disease spinocerebellar ataxia with axonal neuropathy (SCAN1).

Glutathione synthetase (GSS) is the second enzyme in the glutathione biosynthesis pathway. GSS catalyses the condensation of gamma-glutamylcysteine and glycine to form glutathione. Defects in the GSS are the cause of glutathione synthetase deficiency aka GSS deficiency or 5-oxoprolinuria or pyroglutamic aciduria, which is a severe form characterized by an increased rate of hemolysis and defective function of the central nervous system.

Carboxymethylenebutenolidase homolog (CMBL) is a cysteine hydrolase of the dienelactone hydrolase family which is highly expressed in the liver cytosol. CMBL is the human homolog of Pseudomonas dienelactone hydrolase, which is a protein that participates in the bacterial halocatechol degradation pathway. CMBL which preferentially cleaves cyclic esters activates medoxomil-ester prodrugs in which the medoxomil moiety is coupled with an oxygen atom. CMBL is inhibited by PCMB (p-chloromercuribenzoate) and is encoded by a gene which maps to human chromosome 5p15.2. Furthermore, CMBL converts the prodrug olmesartan medoxomil into its pharmacologically active metabolite olmerstatan, which is an angiotensin receptor blocker, in the liver and intestine. CMBL can also activate beta-lactam antibiotics faropenem medoxomil and lenampicillin. CMBL is widely expressed, with the highest levels in the liver, followed by the kidney, small intestine and the colon.

IL17 is a proinflammatory cytokine produced by activated T cells. IL-17 regulates the activities of NF-kappaB and mitogen-activated protein kinases. Interleukin-17 can stimulate the expression of IL6 and cyclooxygenase-2 (PTGS2/COX-2), as well as enhance the production of nitric oxide (NO). High levels of IL-17 are associated with several chronic inflammatory diseases including rheumatoid arthritis, psoriasis and multiple sclerosis.

Uromodulin is the most abundant protein in normal urine. Its secretion in urine follows proteolytic cleavage of the ectodomain of its glycosyl phosphatidylinosital-anchored counterpart that is situated on the luminal cell surface of the loop of Henle. Uromodulin plays a role as a constitutive inhibitor of calcium crystallization in renal fluids. Secretion of uromodulin in urine provides protection against urinary tract infections caused by uropathogenic bacteria. Defects in Uromodulin expression are associated with the autosomal dominant renal disorders medullary cystic kidney disease-2 (MCKD2) and familial juvenile hyperuricemic nephropathy (FJHN). These disorders are characterized by juvenile onset of hyperuricemia, gout, and progressive renal failure. While several transcript variants may exist for this gene, the full-length natures of only two have been described to date. UMOD is involved in regulating the circulating activity of cytokines as it binds to il-1, il-2 and tnf with high affinity.