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Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

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.

BIRC7 is a part of the inhibitor of apoptosis protein (IAP) family and contains a single copy of a baculovirus IAP repeat (BIR) as well as a RING-type zinc finger domain. The BIR domain is necessary for inhibitory activity & cooperates with caspases, while the RING finger domain sometimes increases anti-apoptotic activity but doesn’t inhibit apoptosis by itself. 2 transcript variants encoding diverse isoforms have been found for this gene. The 2 isoforms have dissimilar antiapoptotic characteristics, with isoform a protecting cells from apoptosis induced by staurosporine and isoform b defending cells from apoptosis induced by etoposide.
BIRC7 has direct contact with several caspases together with caspase-3, caspase-7, & caspase –9. BIRC7 inhibits the activation of caspase-9 induced by Apaf-1, cytochrome c, and dATP.

Alpha-cardiac actin belongs to the actin family which is comprised of three main groups of actin isoforms, alpha, beta, and gamma. The alpha actins are found in muscle tissues and are a major constituent of the contractile apparatus. Defects in the cardiac actin have been associated with idiopathic dilated cardiomyopathy (IDC) and familial hypertrophic cardiomyopathy (FHC).

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-a from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

Bivalirudin directly inhibits thrombin by specifically binding as well to the catalytic site and to the anion-binding exosite of circulating and clot-bound thrombin. Bivalirudin is a specific and reversible direct thrombin inhibitor.
Thrombin, which is a serine protease, plays a central role in the thrombotic process; it cleaves fibrinogen into fibrin monomers and activates Factor XIII to Factor XIIIa, allowing fibrin to develop a covalently cross-linked structure which stabilizes the thrombus. Thrombin also activates Factors V and VIII, which promotes further thrombin generation, activates platelets, stimulating aggregation and granule release.

Calumenin is a calcium-binding protein located in the endoplasmic reticulum (ER) and sarcoplasmic reticulum (SR) of mammalian tissues which plays a role in ER functions as protein folding and sorting. Calumenin belongs to a family of multiple EF-hand proteins (CERC) that include reticulocalbin, ERC-55, and Cab45 and the product of this gene. Calumenin binds 7 calcium ions having low affinity and takes part in such ER functions as protein folding and sorting.

CRCP is a ubiquitous coupling protein for the calcitonin gene-related peptide and adrenomedullin receptors. CRCP controls ligand sensitivity in several tissues and has DNA-directed RNA polymerase activity, catalytic activity and calcitonin receptor activity.

NCALD belongs to the neuronal calcium sensor (NCS) family. NCALD is cytosolic at inactive calcium levels; but, high intracellular calcium levels induce a conformational transformation which exposes the myristoyl group, causing protein association with membranes and partial co-localization with the perinuclear trans-golgi network. NCALD protein is a regulator of signal transduction by G protein-coupled receptor.

Colipase (CLPS) is a protein co-enzyme essential for optimal enzyme activity of pancreatic lipase. CLPS is secreted by the pancreas as an inactive form, procolipase, which is then activated in the intestinal lumen by trypsin. CLPS prevents the inhibitory effect of bile salts on the lipase-catalyzed intraduodenal hydrolysis of dietary long-chain triglycerides. CLPS allows lipase to anchor noncovalently to the surface of lipid micelles, counteracting the destabilizing influence of intestinal bile salts. CLPS binds to the C-terminal, non-catalytic domain of lipase, thus stabilizing an active conformation and significantly increasing the whole hydrophobic binding site.

GRPEL1 is a vital component of the PAM complex, a complex necessary for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. GRPEL1 protein controls the nucleotide-dependent binding of mitochondrial HSP70 to substrate proteins.

OTOR proteins is also known as fibrocyte-derived protein (Fdp) and Melanoma inhibitory activity-like (MIAL). Otoraplin is a member of the melanoma-inhibiting activity gene family. Otoraplin is a secreted 16 kDa globular protein that is expressed in the inner ear by periotic mesenchyme and developing and mature fibrocytes. OTOR is highly homologous to MIA/cartilage-derived retinoic acid-sensitive protein (CD-RAP), which is a cartilage-specific protein that is also expressed in malignant melanoma cells. The 111 amino acid mature human otoraplin contains 1 SH3 domain (46 – 107 amino acids) and a Tyr at position 50 that is reportedly sulfated. Otoraplin takes pasrt in the initiation of periotic mesenchyme chondrogenesis.
Otoraplin is secreted through the Golgi apparatus and plays a role in cartilage development and maintenance. A frequent polymorphism in the translation start codon of OTOR can abolish translation and may be associated with forms of deafness.

EFNA3 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors include thelargest subfamily of receptor protein-tyrosine kinases which have been implicated in mediating developmental events, especially in the nervous system and in erythropoiesis. Ephrins are divided into the ephrin-A (EFNA) class and the ephrin-B (EFNB) class, based on their structures and sequence relationships. The Ephrins from the EFNA class are anchored to the membrane by aglycosylphosphatidylinositol linkage, while the others from the EFNB class are transmembrane proteins.

Zinc Finger, CCHC Domain Containing 12 (ZCCHC12) which holds 1 CCHC-type zinc finger is a part of the ZCCHC12 family. ZCCHC12 takes part in the bone morphogenetic protein (BMP)-signaling pathway as a transcriptional coactivator. BMP signaling is positively modulated as a result of the interaction between ZCCHC12 with SMAD1 and the association with CBP in the transcription complex.

Chemokine (C-X-C motif) ligand 5 (CXCL5) is a small cytokine belonging to the CXC chemokine family that is also known as epithelial-derived neutrophil-activating peptide 78 (ENA-78). It is produced following stimulation of cells with the inflammatory cytokines interleukin-1 or tumor necrosis factor-alpha. Expression of CXCL5 has also been observed in eosinophils. This chemokine stimulates the chemotaxis of neutrophils possesses angiogenic properties. It elicits these effects by interacting with the cell surface chemokine receptor CXCR2. The gene for CXCL5 is encoded on four exons and is located on human chromosome 4 amongst several other CXC chemokine genes. CXCL5 has been implicated in connective tissue remodelling.

CMV belongs to the Betaherpesvirinae subfamily of Herpesviridae which includes herpes simplex virustypes 1 and 2, varicella-zoster virus, and Epstein-Barrvirus. The herpesviruses share a characteristic ability to remain latentover long periods. CMV is a double-stranded linear DNA virus with 162 hexagonal protein capsomeres surrounded by a lipid membrane. CMV has the largest genome of the herpes viruses, ranging from 230-240 kilobase pairs. Human CMV is composed of unique and inverted repeats that include the existence of 4 genome isomers caused by inversion of L-S genome components (class E). Replication may be divided into immediate early, delayed early, and late gene expression based on time of synthesis after infection. The DNA is replicated by rolling circles. In vitro, CMV replicates in human fibroblasts.

Syntaxin-11 (STX11) belongs to the t-SNARE family. Syntaxin-11 regulates protein transport between late endosomes and the trans-Golgi network. STX11 interacts with the SNARE proteins SNAP-23 and VAMP. STX11 gene mutations are linked with familial hemophagocytic lymphohistiocytosis.

The precise role of CFLAR is not yet revealed but it seems it is vital in apoptosis regulation downstream of all identified death receptors.

SERPINA1 is secreted and is a serine protease inhibitor which its targets include elastase, plasmin, collagenase, leucocytic proteases, trypsin, chymotrypsin, and plasminogen activator. Defects in SERPINA1 gene can cause emphysema or liver disease. SERPINA1 is an endogenous inhibitor of serine proteases and inhibits the catalytic domain of human recombinant matriptase in vitro. Rise in SERPINA1 occurs as an acute phase response to tissue necrosis and inflammation. mutations in SERPINA1 and SLC11A1 genes change the balance between elastase produced by leukocytes during phagocytosis.

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.

Calmodulin Like 3 (CALML3) is a member of the calmodulin family and contains 4 EF-hand domains. The CALML3 protein may be similar to that of genuine calmodulin and may in fact compete with calmodulin by binding, with different affinities, to cellular substrates. CALML3 protein is expressed in normal mammary, prostate, cervical, and epidermal tissues.

Cold inducible RNA-binding protein (CIRBP) has a protective role in the genotoxic stress response by stabilizing transcripts of genes involved in cell survival. CIRBP localizes to the nucleus and contains one RRM (RNA recognition motif) domain. Expressed ubiquitously, CIRBP is believed to play a crucial role in the suppression of cellular proliferation in response to UV irradiation or extreme cold.

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.

PI3 is an elastase-specific protease inhibitor, which contains a WAP-type four-disulfide core (WFDC) domain, and is thus a member of the WFDC domain family. Most WFDC gene members are localized to chromosome 20q12-q13 in two clusters: centromeric and telomeric. PI3 belongs to the centromeric cluster.