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Hydroxymethylglutaryl-CoA lyase (HMGCL) is a mitochondrial matrix protein which is a member of the HMG-CoA lyase family. HMGCL is a homodimer and participates in leucine catabolism and ketogenesis, the hepatic synthesis of ketone bodies which, during fasting, provides a major source of energy for the heart, brain and kidney. More precisely, HMGCL catalyzes the final step of these processes, the cleavage of 3-hydroxy-3-methylglutaryl-CoA to acetoacetic acid and acetyl-CoA.

Cardiotrophin-like cytokine (CLC/ NNT-1) belongs to the IL-6 family of cytokines. All family members share the receptor subunit gp130, which belongs to the type I cytokine receptor superfamily. NNT1 is a trophic factor for motor neurons, a stimulator of ACTH release from corticotrophs, and an inducer of IgE synthesis and B cell proliferation. Cells expressing NNT-1 include embryonic muscle, lung epithelium, and mesenchyme. NNT1 binds to and activates the ILST/gp130 receptor.

CKMT1A is in charge of the transfer of high energy phosphate from mitochondria to the cytosolic carrier, creatine. CKMT1A is a member of the creatine kinase isoenzyme family and exists as two isoenzymes, sarcomeric MtCK and ubiquitous MtCK, encoded by separate genes. Mitochondrial creatine kinase arises in two different oligomeric forms: dimers and octamers, unlike the exclusively dimeric cytosolic creatine kinase isoenzymes. Numerous malignant cancers with poor prognosis have displayed overexpression of ubiquitous mitochondrial creatine kinase which is linked to high energy turnover and inability to remove cancer cells through apoptosis.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

Viral MIP-2 is closely related to MIP-1α, show amino acid sequence similarity of about 41%. At the amino acid sequence level, Viral MIP-1 and Viral MIP-2 share 48% similarity. Viral MIP-1 and Viral MIP-2 are more closely linked to one another phylogenetically than to other human chemokines, signifying that they have gene duplication within the virus rather than by two independent gene aquisitions. Viral MIP-2 binds to the CCR3 chemokine receptor through which eotaxin and other β chemokines activate eosinophils. Viral MIP-2 activates and chemoattract human eosinphils.

The C3c component is central in both complement activation pathways, with different specific proteolytic systems cleaving it to form C3 convertase. Cleavage of C3 releases C3a and the C3b fragment which is part of the alternative C3 convertase. C3 levels can be low because of decreased synthesis or due to consumption. High C3 levels are seen in highly acute or chronic inflammation, hepatic cholestasis and during the third trimester of pregnancy.
Unwanted complement activation is a major cause of tissue damage in various pathological conditions and contributes to quite a few immune complex diseases.
Compstatin is an effective inhibitor of the activation of complement component C3 and thus blocks a central and essential step in the complement cascade. The specific binding site on C3, the configuration in the bound form, and the exact mode of action of compstatin are unknown. The crystal structure of compstatin in complex with C3c reveals that the compstatin-binding site is formed by the macroglobulin (MG) domains 4 and 5. This binding site is part of the structurally stable MG-ring created by domains MG1–6 and is distant from any other known binding site on C3. Compstatin does not modify the conformation of C3c, while compstatin itself undergoes a large conformational alteration upon binding.

Cholera Toxin B subunit (ctxB) Cholera is a protein complex secreted by the bacterium Vibrio cholerae. ctxB is responsible for the massive, watery diarrhea characteristic of cholera infection. The cholera toxin is an oligomeric complex made up of 6 protein subunits: a single copy of the A subunit and5 copies of the B subunit, denoted as AB5. Subunit B binds while subunit A activates the G protein which activates adenylate cyclase. The five B subunits form a five-membered ring. The A subunit has 2 important segments. The A1 portion of the chain (CTA1) is a globular enzyme payload that ADP-ribosylates G proteins, while the A2 chain (CTA2) forms an extended alpha helix which sits snugly in the central pore of the B subunit ring.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modules: Module I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

Troponin Complex is a heteromeric protein playing an important role in the regulation of skeletal and cardiac muscle contraction. It consists of three subunits, Troponin I, Troponin T and TroponinC. Each subunit is responsible for part of Troponin Complex function. E.g. Troponin I inhibits ATP-ase activity of acto-myosin.Troponin T and Troponin Iare presented in cardiac muscles in different forms than in skeletal muscles. Purified subunits of rcTnI, rcTnC and rcTnT are recomplexed in vitro under appropriate conditions.

SH3-Domain GRB2-Like 3, also known as SH3GL3, is a part of the endophilin family. SH3GL3 contains 1 BAR domain and 1 SH3 domain and takes part in endocytosis. SH3GL3 is a protein coding gene which drafts proteins with high curvature to membranes.

Cathepsin-L also known as CTSL is a member of the peptidase C1 family. CTSL, is a dimer composed of disulfide-linked heavy and light chains, both formed from a single protein precursor. Furthermore, CTSL is a lysosomal cysteine proteinase which takes a main part in intracellular protein catabolism. CTSL substrates include collagen and elastin, as well as alpha-1 protease inhibitor, which is the most important controlling element of neutrophil elastase activity. CTSL has been implicated in a number of pathologic processes, including myofibril necrosis in myopathies and in myocardial ischemia, and in the renal tubular response to proteinuria. Multiple alternatively spliced transcript variants have been found for CTSL.

SH3 domain-binding glutamic acid-rich-like protein (SH3BGRL) belongs to the human SH3BGR family. SH3BGRL gene which is located to chromosome Xq13.3, encodes a small protein of 114 amino acids that is extensively expressed in various tissues including liver and blood. SH3BGRL protein contains a prolinerich sequence (PLPPQIF), which is comprsed of both the SH3 binding (PXXP)3 and the Homer EVH1 binding (PPXXF)4 motif.

Synaptic vesicle membrane docking and fusion is mediated by SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) located on the vesicle membrane (v-SNAREs) and the target membrane (t-SNAREs). The assembled v-SNARE/t-SNARE complex consists of a bundle of four helices, one of which is supplied by v-SNARE and the other three by t-SNARE. For t-SNAREs on the plasma membrane, the protein syntaxin supplies one helix and the protein encoded by this gene contributes the other two. Therefore, SNAP25 product is a presynaptic plasma membrane protein involved in the regulation of neurotransmitter release. The synaptosomal-associated protein (SNAP-25) is an essential component of the core complex that mediates presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters.

CCS is vital for the integration of copper into SOD-1, and as a result is needed for its enzymatic activity. CCS inhibits copper ions from binding to intracellular copper scavengers and provides the SOD-1 enzyme with the required copper cofactor. CCS escorts copper just to SOD-1 and is unable to deliver copper to proteins in the mitochondria, nucleus or secretory pathway. Although many tissues express CCS, the chaperone is most abundant in the kidney, liver and Purkinje cells in the neuropil of the central nervous system.

Lipid hydroperoxide peroxidase (TPX) belongs to the peroxiredoxin family of antioxidant enzymes, which reduce hydrogen peroxide and alkyl hydroperoxides. TPX has an imperative role in thioredoxin peroxidase activity.

Glucokinase also known as GLK is a member of the bacterial glucokinase family. GLK is not highly significant in E.coli since glucoseis already transported into the cell through the PTS system as glucose 6-phosphate.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation.

Ubiquitin Carboxyl-Terminal Esterase L1 (UCHL1) is a part of a family whose products hydrolyze small C-terminal adducts of ubiquitin to create the ubiquitin monomer. UCHL1 is a part of the ubiquitin system, which regulates many biological activities. UCHL1 is a thiol protease that distinguishes and hydrolyzes a peptide bond at the C-terminal glycine of ubiquitin. UCHL1 binds to free monoubiquitin and avoids its degradation in lysosomes.

CISD1 protein holds a CDGSH iron-sulfur domain and is known to bind a redox-active [2Fe-2S] cluster. CISD1 is restricted to the outer membrane of mitochondria and takes part in oxidation regulation.

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. 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.

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.

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.