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C1q is the first component of the classical pathway of complement activation. C1q along with the enzymatically active components C1r and C1s forms the C1 complex. When C1 binds to immunoglobulins in the form of immune complexes, it leads to activation of C1r and C1s proteases and a further activates the classical pathway of complement. C1q is a glycoprotein that belongs to the collectin family, having a molecular weight of about 410-462 kDa. C1q is a hexamer composed of globular heads attached to collagen-like triple-helix tails. The globular heads of C1q exclusively bind to the CH2 domain of IgG molecules or the CH3 domain of IgM. Each heavy chain of the immunoglobulin molecule contains a single binding site for C1q. Given that C1q must bind to no less than two heavy chains in order to alter its conformation and activate C1r and C1s, its activation follows only after binding to immunoglobulins in the form of immune complexes bound to multivalent antigens. C1q’s main physiological role is in the clearance of immune complexes and apoptotic bodies from the organism. Interruption of this process may lead to development of autoimmunity. Individuals with genetic deficiencies of C1q or other components of the classical pathway are at risk to develop SLE. C1q specifically binds to apoptotic bodies of human keratinocytes, vascular endothelial cells and lymphocytes. Complement components C1q and bound C3 mediate the clearance of apoptotic bodies. Hence, C1q may advance the clearance of autoantigens, avoiding stimulation of the immune system. Nonetheless, an extended exposition of the immune system to the neoepitope exposed on C1q molecules bound to immune complexes or apoptotic bodies could ultimately lead to an autoimmune response against C1q itself and to an altered complement function. C1q deficiency may also lead to disruption of the negative selection of autoreactive B cells. C1q along with other specific recognition proteins bind to the highly conserved lupus antigens (dsDNA and nuclear proteins) and activate the complement system. Autoantibodies against C1q (anti-C1q) are found in a number of autoimmune and infectious diseases like glomerulonephritis (GN) and lupus erythematosus (SLE), these antibodies are significant in clinical practice due to their negative predictive value.

Cardiotrophin 1 (CT-1) is a 201 amino acid member of the interleukin-6 superfamily. It was identified by its ability to induce hypertrophic response in cardiac myocytes. CT-1 mRNA levels were found both in cardiac myocytes and in cardiac nonmyocytes. CT 1 was also detected in abundance in normal adult human lung and was expressed in both fetal and adult airway smooth muscle cells. CT 1 activates gp130 dependent signaling and stimulates the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway to transduce hypertrophic and cytoprotective signals in cardiac myocytes.
CT 1 has also a neurotrophic function. CTF1 deficiency causes increased motoneuron cell death in spinal cord and brainstem nuclei of mice during a period between embryonic day 14 and the first postnatal week. Moreover, CT-1 is a hepatocyte survival factor that efficiently reduces hepatocellular damage in animal models of acute liver injury. Cardiotrophin 1 expression is augmented after hypoxic stimulation and it can protect cardiac cells when added either prior to simulated ischaemia or at the time of reoxygenation following simulated ischaemia. Cardiotrophin 1 can induce expression of the protective heat shock proteins (hsps) in cardiac cells.
Cardiotrophin-1 increased ventricular expression of ANP, brain natriuretic peptide (BNP) and angiotensinogen mRNA.
Cardiophin 1 levels were significantly elevated in patients with heart failure, patients with dilatative cardiomyopathy, moderate/severe mitral regurgitation, stable and unstable angina and after acute myocardial infarction.

Methionine sulfoxide reductase B1 (SEPX1 or MSRB1), is a selenoprotein that contains a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded by the UGA codon that usually signals translation termination. SEPX1 is a member of the methionine sulfoxide reductase B (MsrB) family, and is expressed in an assortment of adult and fetal tissues. MSRs (Methionine sulfoxide reductases) catalyze the reduction of free and protein-bound methionine sulfoxides to corresponding methionines. The oxidation of methionine by ROS creates a diastereomeric mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). Two separate enzyme families evolved for reduction of these sulfoxides, with methionine-S-sulfoxide reductase (MsrA) being stereospecific for Met-S-SO and methionine-R-sulfoxide reductase (MsrB) for Met-R-SO.

SLC3A2, also known as Solute Carrier Family 3 Member 2, is a single-pass type II membrane protein which is part of the SLC3A transporter family. SLC3A2 is expressed ubiquitously in all tissues tested with the highest levels detected in kidney, placenta and testis and lowest level in thymus. SLC3A2 is essential for the function of light chain amino-acid transporters and also takes part in sodium-independent, high-affinity transport of large neutral amino acids such as phenylalanine, tyrosine, leucine, arginine and tryptophan. SLC3A2 participates in guiding and targeting of LAT1 and LAT2 to the plasma membrane.

Non-Metastatic Cells 3 or NME3 is a possible suppressor of metastasis. NME3 can be found at a lower levels in greatly metastatic cells when compared to cells that has less metastatic potential NME3 is crucial for the nucleoside triphosphates synthesis, also, in apoptosis induction & hematopoiesis. NME3 is can be expressed during early stages of myeloid differentiation of greatly purified CD34+ cells.

Suppressor of Cytokine Signaling 3, also known as SOCS3 belongs to the SOCS family; in addition SOCS3 is a member of the STAT-induced STAT inhibitor (SSI). The SSI family members are cytokine-inducible negative regulators of cytokine signaling. The expression of SOCS3 is induced by different cytokines, including IL6 and IL10. SOCS3 can bind to JAK2 kinase, and inhibit the activity of JAK2 kinase. Studies of the mouse counterpart of SOCS3 have shown the roles of SOCS3 in the negative regulation of fetal liver hematopoiesis, and placental development.

IFNGR1 is a part of the hematopoietic cytokine receptor superfamily. IFNGR1 forms a site that is recognized by the extracellular domain of IFNGR2 by inducing the rapid dimerization of chains. IFNGR1 Plays an important role in the IFN-gamma pathway that is essential for the cellular response to infectious agents. IFNGR1 is expressed in a membrane-bound form in various cells, and is over-expressed in tumor cells.

Neuregulin/Heregulin is a family of structurally related polypeptide growth factors which are stemmed from alternatively spliced genes (NRG1, NRG2, NRG3 and NRG4). There are more than 14 soluble and transmembrane proteins derived from the NRG1 gene. Proteolytic processing of the extracellular domain of the transmembrane NRG1 isoforms release soluble growth factors. These isoforms contain the heregulins (HRGs), glial growth factors (GGFs) and sensory and motor neuron-derived factor (SMDF). All these factors have the Ig and EGF-like domain, and are able to bind to ErbB3 and ErbB4 receptor tyrosin kinases. This binding stimulates erb3 and erb4 heterodimerization with erb2, promoting intrinsic kinase activity, which results in tyrosine phosphorylation. NRG1 isoforms induce the growth and differentiation of epithelial, neuronal, glial, and other types of cells.

Obg-like ATPase 1 (OLA1) acts as a negative regulator of the cellular antioxidant response independent of transcriptional processes. OLA1 curbs the antioxidant response via nontranscriptional mechanisms. OLA1 hydrolyzes ATP, and can also hydrolyze GTP with lower efficiency. OLA1 is clearly down-regulated by DNA damage-inducing agents. OLA1 is expressed in all tissues; however it is more abundant in the testis, liver, lung, and brain. OLA1 is overexpressed in a number of malignancies, including cancers of the colon, rectum, ovary, lung, stomach, and uterus.

OLR1 is a type II membrane protein which belongs to the C-type lectin family and performs as a cell-surface receptor for Ox-LDL. Ox-LDL has a part in early ather-osclerosis, which includes the transformation of monocyte-derived macro-phages to foam cells in atherosclerotic lesions. In addition, OLR1 protein triggers the activation of the NF?B signal transduction pathway.

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.

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.

FGFR1 oncogene partner (FGFR1OP) is a member of the FGFR1OP family. The FGFR1OP protein is an essentially hydrophilic protein proposed to be a leucine-rich protein family member. A t(6;8)(q27;p11) chromosomal translocation, fusing the FGFR1OP gene and the FGFR1 gene, is seen in cases of myeloproliferative disorder. The ensuing chimeric protein contains the N-terminal leucine-rich region of the FGFR1OP protein fused to the catalytic domain of FGFR1. The FGFR1OP gene is believed to play a significant role in normal proliferation and differentiation of the erythroid lineage.

Kallikreins are serine protease enzymes having various physiological functions.
Kallikreins are implicated in carcinogenesis and have potenital as novel cancer disease biomarkers. KLK1 is one of the fifteen kallikrein subfamily members located in a cluster on chromosome 19. KLK1 is functionally conserved in its ability to release the vasoactive peptide, Lys-bradykinin, from low molecular weight kininogen.
Human Kallikrein-1, also called as Kallidinogenase, Kininogenase or Kininogenin, is an active protein enzyme present in saliva, pancreatic juices, and urine that catalyzes the proteolysis of bradykininogen to bradykinin.
Kallikrein-1, which derived from human or porcine, have been used as drugs for a long time, they are mainly used in the treatment f light to medium hypertension and occlusion of cerebral and surrounding blood vessels.
KLK1 demonstrates both trypsin- and chymotrypsin-like selectivities with Tyr/Arg preferred at site P1, Ser/Arg strongly preferred at P1', and Phe/Leu at P2.
rs5517 in the KLK1 gene is considerably connected with hypertension in a Chinese Han population. KLK1 is expressed de novo in endothelial cells and mediates relaxation of human umbilical veins. The K allele of KLK1 promoter and TT genotype of TGF-beta1 are a genetic KLK1 -130 GN and -128 G-C, and the defenselessness factor contributing to progressive renal descent in Taiwanese primary vesicoureteric reflux children.
Induction of KLK1 in carotid arteriosclerosis doesn’t lead to kallikrein-kinins pathway activation. Transgenic rats expressing KLK1 have impaired renal response to acute volume expansion Endothelial cells synthesize and release active form of KLK1on the surface which is important function in maintenance of circulation homeostasis.
KLK1 participates in epidermal desquamation through cleavage of desmoglein 1 and regulation by lympho-epithelial Kazal-type-related inhibitor (LEKTI).

Tripartite Motif Containing 33 (TRIM33) belongs to the tripartite motif family. This motif includes 3 zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. TRIM33 is assumed to be a transcriptional corepressor. TRIM33 functions as an E3 ubiquitin-protein ligase. TRIM33 also promotes SMAD4 ubiquitination, nuclear exclusion and degradation via the ubiquitin proteasome pathway. In addition, TRIM33 inhibits the transcriptional response to TGF-beta/BMP signaling cascade. Furthermore, TRIM33 has a role in the control of cell proliferation.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 7 (CEACAM7) is a member of the immunoglobulin superfamily, CEA family. CEACAM7 contains 1 Ig-like C2-type (immunoglobulin-like) domain and 1 Ig-like V-type (immunoglobulin-like) domain. CEACAM7 is intensely down-regulated in colonic adenocarcinomas.

GSTO1 belongs to the theta class glutathione S-transferase-like (GSTTL) protein family. GSTO1 is expressed in a broad array of human tissues and exhibits glutathione-dependent thiol transferase and dehydroascorbate reductase activities as well as catalyzing the reduction of monomethylarsonate which is an intermediate in the pathway of arsenic biotransformation. Furthermore, GSTO1 shields from oxidative stress which is a risk factor for Alzheimer disease, vascular dementia and stroke. GSTO1 is abundant in alveolar macrophages and airway secretions, with the levels reduced in chronic obstructive pulmonary disease patients. In mouse, the GSTO1 protein acts as a small stress response protein, probably involved in cellular redox homeostasis.

PYCR1 is a universal housekeeping enzyme which catalyzes the NAD(P)H-dependent conversion of pyrroline-5-carboxylate to proline. PYCR1 enzyme also takes a physiologic part in the generation of NADP(+) in certain cell types. PYCR1 forms a homopolymer and localizes to the mitochondrion. Mutations in PYCR1 are the source of cutis laxa autosomal recessive type 2B (ARCL2B).

RAET1L plays a role as a stress-induced ligand for NKG2D receptor. Retinoic Acid Early Transcript 1L (RAET1L) is linked to the cell membrane by the GPI anchor. HCMV infection triggers RAET1L’sexpression but HCMV alters its function. HCMV-encoded UL16 glycoprotein retains RAET1L/ULBP6 inside the cells, preventing it from reaching the cell surface and being exposed to cells of the immune system. RAET1L has a more restricted expression profile in cell lines and primary human tissues than other NKG2D ligands.

Hepatitis A virus cellular receptor 1 (HAVCR1) is a membrane receptor for both human hepatitis A virus (HHAV) and TIMD4. HAVCR1 is a type I trans-membrane structural glycoprotein located in the renal proximal tubule epithelial cells. HAVCR1 protein may be involved in the control of asthma and allergic diseases. The reference genome represents an allele which retains a MTTVP amino acid segment that presents defense against atopy in HHAV seropositive individuals.

Thrombopoietin or TPO or MGDF, is a protein (glycoprotein hormone) that can be found in the liver and kidney tissues. TPO regulates the creation of platelets. The protein enhances the production & differentiation of cells such as megakaryocytes that are part of the bone marrow cells that secretes a wide number of platelets. The cellular development process that ends up in the production of platelet calls (Megakaryocytopoiesis). Humoral growth factor is needed for the megakaryocyte proliferation & maturation of megakaryocyte, not apart from thrombopoiesis.

Hepatoma Derived Growth Factor-Like 1 (HDGFL1) is a member of the HDGF family and contains 1 PWWP domain.

Neuregulin/Heregulin is a family of structurally related polypeptide growth factors which are stemmed from alternatively spliced genes (NRG1, NRG2, NRG3 and NRG4). Thus far, there are more than 14 soluble and transmembrane proteins derived from the NRG1 gene. Proteolytic processing of the extracellular domain of the transmembrane NRG1 isoforms release soluble growth factors. HRG1-b1 is comprised of an Ig domain and an EGF-like domain which is necessary for direct binding to receptor tyrosine kinases erb3 and erb4. This binding stimulates erb3 and erb4 heterodimerization with erb2, promoting intrinsic kinase activity, which results in tyrosine phosphorylation. Even though HRG1-b1 biological effects are still unclear, it has been discovered to advance motility and invasiveness of breast cancer cells which in addition might entail up-regulation of expression and function of the autocrine motility-promoting factor (AMF).