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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.

CRYGC is a member of the beta/gamma-crystallin family. Mammalian lens crystallins are distributed into alpha, beta, and gamma families; beta and gamma crystallins are also considered as a superfamily. Gamma-crystallins are a homogeneous group of extremely symmetrical, monomeric proteins usually missing connecting peptides and terminal extensions and are differentially regulated after early development. Three pseudogenes (gamma-E,F,G) and four gamma-crystallin genes (gamma-A,B,C,D) are structured in a genomic sector as a gene cluster. Gamma-crystallins are involved in cataract formation as a result of aging or mutations in specific genes. Mutations in CRYGC result in cataract Coppock-like (CCL) and cataract autosomal dominant (ADC).

MIG (CXCL9) is a small cytokine which is part of the CXC chemokine family. MIG, which is also recognized as monokine is induced by gamma interferon. MIG is related to 2 other CXC chemokines named CXCL10 and CXCL11, whose genes are located next to the gene for CXCL9 on human chromosome 4. CXCL9, CXCL10 and CXCL11 obtain their chemotactic functions by interacting with the chemokine receptor CXCR3.

Adiponectin is an adipocyte specific secreted protein that circulates in the plasma. It is induced during adipocyte differentiation and its secretion is stimulated by insulin. Mouse adiponectin shares about 83% amino acid identity with that human. Adiponectin plays a role in various physiological processes such as energy homeostasis and obesity. Adiponectin is reduced in obese humans, and decreased level is associated with insulin resistance and hyperinsulinemia.

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, eosinophilsand 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.

Collagen triple helix repeat-containing protein 1 (CTHRC1) functions as a negative regulator of collagen matrix deposition. CTHRC1 is a secreted 28kDa protein which is glycosylated and highly conserved from lower chordates to mammals. CTHRC1 is highly connected with calcified tissues and cartilaginous matrix, but not with endothelial cells. CTHRC1 is detected qualitatively in plasma of healthy human subjects. CTHRC1 plasma levels are also significantly elevated during pregnancy, in diabetes, in inflammatory and infectious conditions, in subjects with acute myeloid leukemia but not in subjects with solid cancers. The hormonal functions of CTHRC1 include regulation of lipid storage and cellular glycogen levels with potentially far-reaching implications for cell metabolism and physiology. CTHRC1 gene deletion leads to fatty liver (steatosis) formation in mice while others exhibited inactivation of the CTHRC1 gene also results in low bone mass.

SAR1B is a small GTPase that functions as a homodimer. GTP-Binding Protein SAR1B (SAR1b) is involved in transport from the endoplasmic reticulum to the Golgi apparatus and also in the selection of the protein cargo and the assembly of the COPII coat complex. The SAR1B protein is activated by the guanine nucleotide exchange factor PREB. SAR1B gene defects are a cause of chylomicron retention disease (CMRD), also known as Anderson disease (ANDD).

DDX39A which is a part of the DEAD box protein family is characterized by the conserved motif Asp-Glu-Ala-Asp. This pattern is implicated in a various cellular processes involving alteration of RNA secondary structure, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Several members of the DEAD box protein family are taking part in embryogenesis, spermatogenesis, and cellular growth and division.

MYCBP is a member of the AMY1 family. MYCBP (c-Myc binding protein) binds to the transactivation domain of c-Myc and stimulates the activation of E-box-dependent transcription. MYCBP translocates from the cytoplasm to the nucleus during S phase when increased expression of c-Myc occurs. MYCBP also associates with AKAP 149 and AKAP 84 in mitochondria of somatic cells and sperm, suggesting a role for MYCBP in spermatogenesis. MYCBP is highly expressed in the heart, placenta, pancreas, skeletal muscle and kidney. It is also present at low levels in the lung.

SEPT5 is a member of the septin gene family of nucleotide binding proteins which were initially defined in yeast as cell division cycle regulatory proteins. Septins are extremely conserved in yeast, Drosophila, and mouse and seem to regulate cytoskeletal organization. Interference of septin function disrupts cytokinesis and results in high multinucleate or polyploid cells.

HSPA9 is part of the heat shock protein 70 family which contains both heat-inducible and constitutively expressed members that are also called heat-shock cognate proteins. HSPA9 encodes a heat-shock cognate protein that is involved in the control of cell proliferation and acts as a chaperone. HSPA9 was restricted to chromosome 5, band q31, a region that is often deleted in myeloid leukemias and myelodysplasia (MDS), making it a candidate tumor suppressor gene, which is consistent with the biological function of its murine homologue. HSPA9 supresses nuclear translocation, transcriptional activation, and control of centrosome-duplication functions of p53.

ICAM-3/CD50, or CD50 or Cluster of Differentiation 50 is a protein, part of the intercellular adhesion molecule superfamily. every ICAM peptides are type I transmembrane glycoproteins, bind to leukocyte adhesion LFA-1 & has 2-9 immunoglobulinlike C2-type domains. ICAM-3/CD50 can be found in every leukocyte and acts as a crucial ligand for LFA-1 in the start of the immune system response. ICAM-3/CD50 acts as an adhesion molecule and is also a potent signaling protein.

60S ribosome subunit biogenesis protein NIP7 homolog (NIP7) belongs to NIP7 family and contains 1 PUA domain. NIP7 interacts with pre-ribosome complex and may bind to RNA. NIP7 is vital for proper 27S pre-rRNA processing and 60S ribosome subunit assembly.

ATOX1 is a metal transport protein that is part of the ATX1 family. ATOX1 is a copper chaperone that takes part in cellular antioxidant defense and can bind and deliver cytosolic copper to the copper ATPase proteins in the trans-Golgi network for later incorporation to the ceruloplasmin. ATOX1 plays a role as an antioxidant against superoxide and hydrogen peroxide, and consequently, takes an important part in cancer carcinogenesis. Because of ATOX1 cytogenetic location, the gene can be a good a candidate gene for 5q-syndrome.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

STUB1, is a cytoplasmic protein whose amino acid sequence is highly preserved across species. STUB1 interacts with the molecular chaperones Hsc70-Hsp70 and Hsp90 through its TPR domain, whereas its U-box domain contains its E3 ubiquitin ligase activity. STUB1 interaction with these molecular chaperones lead to in client substrate ubiquitylation and degradation by the proteasome. therefore, STUB1 acts to tilt the folding-refolding mechanism towards the degradative pathway, and it serves as a link between the two. STUB1 inhibits anchorage-independent cell growth and metastatic potential by degrading oncogenic proteins including SRC-3. Inhibition of tyrosine kinase activity of Her-2/neu by quercetin specifies an lateration in the Her-2/neu structure which promotes STUB1 recruitments and down-regulation of Her-2/neu. STUB1 recognizes and mediates degradation of toxic, oligomeric forms of alphaSyn.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

ERP44 is an endoplasmic reticulum chaperone that takes part in thiol-dependent retention of the primary secretory pathway, forming mixed disulfides with substrate proteins through its conserved CRFS motif. ERP44 inhibits the calcium channel activity of ITPR1. ERP44 is involved in the control of oxidative protein folding in the endoplasmic reticulum.

ETHE1 is a mitochondrial sulfur dioxygenase involved in catabolism of sulfide that accumulates to toxic levels in ethylmalonic encephalopathy. Mutations of ETHE1 were detected in all the typical ethylmalonic encephalopathy patients analysed, but no ETHE1 mutations were identified in patients presenting with early onset progressive encephalopathy with ethylmalonic aciduria.

Listeria monocytogenes is a pathogenic bacteria that manufactures flagella.At 37 °C inside humans, it causes MogR to repress the expression of flagellar proteins, thus stopping the manufacturing of flagella. Though, in the low-temperatures externally of the host, the GmaR inactivates MogR, enabling flagellar formation.

GADD45G is part of the nuclear proteins to interact with various proteins whose transcript levels are raised after stressful growth arrest conditions and treatment with DNA-damaging agents. GADD45G reacts to environmental stresses by mediating activation of the p38/JNK pathway which is mediated through their protein binding and activating MTK1/MEKK4 kinase, which is an upstream activator of both p38 and JNK MAPKs. GADD45G acts as a new-age tumor suppressor however is being frequently inactivated epigenetically in multiple tumors. GADD45G mRNA expression is down-regulated in hepatocellular carcinoma. GADD45G causes cell cycle arrest at G2/M transition when transfected into Hep-G2 cells. GADD45 Gamma induction by androgens involves new protein synthesis. Overexpression of GADD45 Gamma inhibits cell growth and causes morphological modifications in prostate cell lines thus GADD45 gamma takes part in differentiation induction by androgens.

CTK-19 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. Unlike its related family members, this smallest known acidic cytokeratin is not paired with a basic cytokeratin in epithelial cells. It is specifically expressed in the periderm, the transiently superficial layer that envelopes the developing epidermis. The type I cytokeratins are clustered in a region of chromosome 17q12-q21.

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.

CDK5 Regulatory Subunit Associated Protein 3 (CDK5RAP3) is a potential regulator of CDK5 activity via its interaction with CDK5R. Neuronal CDC2-like kinase, which is involved in the regulation of neuronal differentiation, is comprised of a catalytic subunit, CDK5, nad an activating subunit, p25NCK5A. CDK5RAP3 binds to p25NCK5A and hence may be involved in neuronal differentiation.