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Excess adiposity is the most important risk in the development of type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-a, and IL-6, that modulate sensitivity and appear to play an important role in the pathogenesis, diabetes, dyslipidemia, inflammation, and atherosclerosis. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts mimetic effects that are dose-dependent and quantitatively similar to stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its mimetic effects, visfatin was as effective in reducing hyperglycemia in deficient diabetic mice. Visfatin was also found to be bound to and activate receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin did not compete for binding to the receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

C-Src Tyrosine Kinase, also known as CSK, regulates cell growth, migration, differentiation, and immune response. CSK Phosphorylates tyrosine residues located in the C-terminal tails of Src-family kinases. CSK is a protein coding gene which suppresses signaling by several surface receptors. Among CSK's related pathways are PI-3K cascade and Signaling by FGFR.

Nectin-1, also referred to as ED4, is a poliovirus receptor- related 1 protein is a part of the Nectin family. Nectin-1 endorses cell-cell contacts by forming homophilic or heterophilic trans-dimers. Heterophilic interactions among PVRL1/nectin-1 & PVRL4/nectin-4 and among PVRL1/nectin-1 & PVRL3/nectin-3 have been found. Nectin-1 acts as an entry receptor for herpes simplex virus & pseudorabies virus as well. Likewise, Neurite outgrowth-promoting activity has been shown by Nectin-1.

Lysyl Oxidase also known as LOX is an extracellular copper enzyme which initiates the crosslinking of collagens and elastin. LOX catalyzes oxidative deamination of the epsilon-amino group in certain lysine and hydroxylysine residues of collagens and lysine residues of elastin. Adding up to crosslinking extracellular matrix proteins, LOX plays a part in tumor suppression. Moreover, defects in LOX are the cause of autosomal recessive cutis laxa type I, CL type I. Two transcript variants encoding dissimilar isoforms have been found for LOX.

Galectin-3 mediates with the alpha-3, beta-1 integrin the stimulation by cspg4 of endothelial cells migration. Galectin-3 plays an necessary part during the acquisition of vasculogenic mimicry and angiogenic properties associated with melanoma progression. LGALS3 overexpression is highly expressed in early stages of papillary carcinoma, and its expression intensity declines during tumor progression. Serum levels of LGALS3 are high in patients with thyroid malignancy but there is considerable overlap in serum LGALS3 concentrations between those with benign and malignant nodular thyroid disease. LGLAS3 takes part as an immune regulator to inhibit T-cell immune responses and promote tumor growth, as a result providing a new mechanism for tumor immune tolerance.

Angiotensin is an oligopeptide in the blood that causes vasoconstriction, increased blood pressure, and release of aldosterone from the adrenal cortex. It is a powerful dipsogen. It is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. It plays an important role in the renin-angiotensin system.
The protein encoded by this gene, pre-angiotensinogen or angiotensinogen precursor, is expressed in the liver and is cleaved by the enzyme renin in response to lowered blood pressure. The resulting product, angiotensin I is then cleaved by angiotensin converting enzyme (ACE) to generate the physiologically active enzyme angiotensin II. The protein is involved in maintaining blood pressure and in the pathogenesis of essential hypertension and preeclampsia.

The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

Norrie Disease (NDP) is a secreted regulatory protein which activates the canonical Wnt signaling pathway through FZD4 and LRP5 coreceptor. NDP takes part in retinal vascularization by acting as a ligand for FZD4 which signals through stabilizing beta-catenin (CTNNB1) and activating LEF/TCF-mediated transcriptional programs. NDP is involved in a pathway that regulates neural cell differentiation and proliferation and also in neuroectodermal cell-cell interaction.

Isopentenyl-diphosphate isomerase 1 (IDI1) belongs to the IPP isomerase type I family and is involved in cholesterol biosynthesis. IDI1 is a peroxisomally-localized enzyme which catalyzes the interconversion of isopentenyl diphosphate (IPP) to its highly electrophilic isomer, dimethylallyl diphosphate (DMAPP), which is the substrate for the sequential reaction that results in the synthesis of farnesyl diphosphate and, eventually, cholesterol. Peroxisomal deficiency diseases such as Zellweger syndrome and neonatal adrenoleukodystrophy show a reduction in IPP isomerase activity.

Peptidase Inhibitor 3, also referred to PI3, is neutrophil and pancreatic elastase-specific inhibitor of skin. The protein may prevent elastase mediated tissue proteolysis. PI3 has shown inhibition of alpha-4-beta-2/CHRNA2-CHRNB2 nicotinic acetylcholine receptor, a weak inhibition on Kv11.1/KCNH2/ERG1 and on the transient receptor potential cation channel subfamily V member 1.

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 modulesModule 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.

Mammalian crystallins which are water soluble structural proteins located in the vertebrate eye are classified in three forms, labeled alpha, beta and gamma. Crystallins, the primary components of the lens, raise the refractive index of the eye all through the accommodation by creating high-molecular weight aggregates that maintain transparency. CRYGS is a monomer that does not aggregate. CRYGS encodes the most substantial gamma-crystallin in adult eye lens tissue. Gamma-crystallins has a part in cataract formation due to aging or mutations in specific genes,

ACOT11 belongs to the acyl-CoA thioesterase family which catalyses the transformation of activated fatty acids to the equivalent non-esterified fatty acid and coenzyme A. Expression of a mouse homolog in brown adipose tissue is induced by low temperatures and inhibited by high temperatures. Obesity-resistant mice demonstrated High levels of expression compared with obesity-prone mice, indicating BFIT takes part in acyl-CoA thioesterase 11 in obesity. BFIT has acyl-CoA thioesterase activity towards medium (C12) and long-chain (C18) fatty acyl-CoA substrates.

CST4 is a member of the cystatin superfamily which contains proteins that hold multiple cystatin-like sequences. Several family members are active cysteine protease inhibitors, whereas others have lost or possibly never attained this inhibitory activity. CST4 strongly inhibits papain (non-competitively) and ficin, partially inhibits stem bromelain and bovine cathepsin C, however does not inhibit porcine cathepsin B or clostripain.

S100 calcium binding protein A5 (S100A5) belongs to the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 family members are localized in the cytoplasm and/or nucleus of a wide range of cells, and are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A5 has a Ca2+ affinity 20-100 fold higher than the other S100 proteins investigated under identical conditions. Furthermore, S100A5 protein binds Zn2+ and Cu2+, and Cu2+ strongly which harms the binding of Ca2+. S100A5 is expressed in very limited regions of the adult brain.

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.

Elcatonin is a Calcitonin derivative which is transformed from eel´s calcitonin by changing the S-S bond into the stable C-N bond. It inhibits the absorption and autolysis of bones, thus leads to blood calcium descending. In addition, it inhibits the bone salts dissolving and transferring and promotes the excretion of calcium and phosphorus in urine. Meanwhile, it inhibits renal tubules reabsorbing calcium, phosphorus and sodium and keeps blood calcium at normal level. It is mainly used for remitting or eliminating the pain caused by Osteoporosis.

CASQ2 belongs to the calsequestrin family and is localized to the sarcoplasmic reticulum in cardiac and slow skeletal muscle cells. CASQ2 is a calcium binding protein that stores calcium for muscle function. The discharge of calcium bound to CASQ2 through a calcium release channel activates muscle contraction. CASQ2 binds 40 to 50 moles of calcium. CASQ2 mutations result in stress-induced polymorphic ventricular tachycardia, also called catecholaminergic polymorphic ventricular tachycardia 2 which is known fir its bidirectional ventricular tachycardia that causes cardiac arrest.

Filamin is a large (270kd) dimeric actin crosslinking protein from a variety of sources, which helps to stabilize the 3D cortical actin network. The fundamental structure of filamin is well conserved and consists of an actin binding domain at the N-terminus followed by a C-terminal rod domain consisting of numerous repeat segments ranging from 4 in C. elegans to 24 in mammalian cells. Each repeat in the rod domain consists of roughly 100 residues and forms an immunoglobulin like fold. Such immunoglobulin folds have been found in a variety of proteins and are responsible for protein-protein interactions. Filamin Human actin-binding protein (ABP), aka filamin, crosslinks actin filaments into orthogonal networks in cortical cytoplasm and participates in the anchoring of membrane proteins for the actin cytoskeleton. Mammalian filamin interacts directly with at least 30 proteins such as transmembrane receptors, second messenger-associated proteins, protein kinases, phosphatases and cytoskeletal proteins and these interactions have been shown to require one or more of the repeat elements in the rod domain.

Cytokeratin 16, also known as KRT16, is a member of the keratin gene family. KRT16 which acts as a regulator of innate immunity in response to skin barrier breach is required for some inflammatory checkpoint for the skin barrier maintenance. KRT16 is coexpressed with keratin 14 in a few epithelial tissues as esophagus, tongue, and hair follicles.