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RAC1 is a GTPase which belongs to the RAS superfamily of small GTP-binding proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. RAC-1 regulates the actin cytoskeleton but also other cellular processes. RAC1 have been shown to be involved in the regulation of cell-cell adhesion.

Thyroglobulin (TG) represents one of the main autoantigenic targets in autoimmune thyroid disease of humans. TG is a large globular dimeric glycoprotein with a total molecular weight of 660 kDa, which occupies a key precursor role in the biosynthesis of the thyroid hormones. Approximately 75% of the total protein content of the thyroid follicle consists of TG. The thyroid gland uses the Thyroglobulin in order to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3). Thyroglobulin is produced by the thyroid epithelial cells (thyrocytes) which form spherical follicles. Thyroglobulin is subsequently secreted and stored in the follicular lumen.
Patients with Hashimoto's thyroiditis or Graves' disease, frequently develop antibodies against Thyroglobulin. Tg-specific antibodies help in the diagnosis of the above diseases, however they also may be present in apparently healthy euthyroid individuals. Blood Thyroglobulin levels can be used as a tumor marker for certain kinds of thyroid cancer, and the may also be elevated in cases of Graves' disease.

Activins are homodimers or heterodimers of the different ? subunit isoforms, part of the TGF? family. Mature Activin A has two 116 amino acids residues betaA subunits (bA-bA). Activin displays an extensive variety of biological activities, including mesoderm induction, neural cell differentiation, bone remodelling, haematopoiesis, and reproductive physiology. Activins takes part in the production and regulation of hormones such as FSH, LH, GnRH and ACTH. Cells that are identified to express Activin A include fibroblasts, endothelial cells, hepatocytes, vascular smooth muscle cells, macrophages, keratinocytes, osteoclasts, bone marrow monocytes, prostatic epithelium, neurons, chondrocytes, osteoblasts, Leydig cells, Sertoli cells, and ovarian granulosa cells.

Seryl-tRNA synthetase, cytoplasmic (SARS) is a member of the class-II aminoacyl-tRNA synthetase family. Aminoacyl-tRNA synthetases’ role is to catalyze the aminoacylation of tRNAs by their corresponding amino acids, as a result linking amino acids with tRNA-contained nucleotide triplets. The SARS enzyme catalyzes the attachment of serine to tRNA (Ser). SARS enzyme is probably able to aminoacylate tRNA (Sec) with serine, to form the misacylated tRNA L-seryl-tRNA (Sec), which will be then converted into selenocysteinyl-tRNA (Sec).

Resistin, also known as adipose tissue-specific secretory factor (ADSF) is a cysteine-rich peptide derived from adipose tissue. Resistin takes part in the inflammatory response, glucose metabolism, and angiogenesis.Resistin blocks insulinstimulated uptake of glucose by adipocytes and promote glucose release by hepatocytes. As such,Resistin considered to participate in diet‑induced insulin-sensitivity. Resistin causes high levels of lowdensity lipoprotein (LDL), increasing the risk of heart disease.

ACTN1 encodes a nonmuscle, cytoskeletal, alpha actinin isoform and maps to the same site as the structurally similar erythroid beta spectrin gene. Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments.

ANXA5 is a member of the annexin family of calcium-dependent phospholipid binding proteins which are involved in membrane-related activity along exocytotic and endocytotic pathways. ANXA5 is a phospholipase A2 and protein kinase C inhibitory protein with calcium channel properties and takes part in cellular signal transduction, inflammation, growth and differentiation. ANXA5 is an anticoagulant protein that acts as an indirect inhibitor of the thromboplastin-specific complex, which is involved in the blood coagulation cascade. ANXA5 regulates coagulability in the blood stream by binding to phosphatidylserine and sulfatide. ANXA5 protects sinsuoidal endothelial cells from ischemia reperfusion damage. ANXA5 is necessary for normal CFTR chloride channel activity.

Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

Osteocrin is a recently identified secreted protein expression of which was only detected in bone, peaking just after birth and decreasing markedly with age. A 1280-bp mRNA encodes osteocrin producing a mature protein of 103 amino acids with a molecular mass of 11.4 kDa. In primary osteoblastic cell cultures osteocrin expression coincided with matrix formation then decreased in very mature cultures. Treatment of cultures with 1,25-dihydroxyvitamin D3 resulted in a rapid dose- dependent down-regulation of osteocrin expression, suggesting direct regulation. Chronic treatment of primary cultures with osteocrin-conditioned media inhibited mineralization and reduced osteocalcin and alkaline phosphatase expression. These results suggest that osteocrin represents a novel, unique vitamin D-regulated bone-specific protein that appears to act as a soluble osteoblast regulator.

Obestatin is a hormone that is produced in the cells lining the stomach and small intestine of several mammals including humans; it drastically reduces appetite in mice and is expected to do the same in humans. Obestatin is a peptide hormone - a relatively small protein. It is encoded by the same gene that also encodes ghrelin, a peptide hormone that increases appetite. The protein produced by that gene breaks into two smaller peptides, ghrelin and obestatin. Ghrelin is an endogenous ligand for the growth hormone secretagogue receptor and is involved in regulating growth hormone release. Ghrelin is derived from a preprohormone called preproghrelin, which also generates a second peptide called obestatin. Ghrelin is an endogenous ligand for the orphan G protein-coupled receptor GPR39 and is involved in satiety and decreased food intake.

The protein encoded by this gene is a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily. The superfamily includes large families of growth and differentiation factors. Bone morphogenetic proteins were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site. This particular family member plays an important role in the onset of endochondral bone formation in humans, and a reduction in expression has been associated with a variety of bone diseases, including the heritable disorder Fibrodysplasia Ossificans Progressiva. Alternative splicing in the 5' untranslated region of this gene has been described and three variants are described, all encoding an identical protein.

Aminoacyl-tRNA synthetases are a class of enzymes which charge tRNAs with their cognate amino acids. Asparaginyl-tRNA synthetase (NARS) is localized to the cytoplasm and is a member of the class II family of tRNA synthetases. The N-terminal domain characterizes the signature sequence for the eukaryotic asparaginyl-tRNA synthetases.

Endoglin is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex.The Endoglin protein consists of a homodimer of 180 kDA with disulfide links. Endoglin has been found on endothelial cells, activated macrophages, fibroblasts, and smooth muscle cells. Furthermore, Endoglin has been found to be part of the TGF-beta1 receptor complex. Endoglin thus may be involved in the binding of TGF-beta1, TGF-beta3, activin-A, BMP-2, and BMP-7. Beside TGF-beta signaling endoglin may have other functions. It has been postulated that endoglin is involved in the cytoskeletal organization affecting cell morphology and migration. Endoglin has a role in the development of the cardiovascular system and in vascular remodeling. Endoglin expression is regulated during heart development . Experimental mice without the endoglin gene die due to cardiovascular abnormalities.

Vascular endothelial growth factor is an important signaling protein involved in both vasculogenesis and angiogenesis. As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/ macrophagemigration, neurons, cancer cells, kidney epithelial cells ).VEGF mediates increased vascular permeability, induces angiogenesis, vasculogenesis and endothelial cell growth, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesisand cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor.
Elevated levels of this protein are linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

ASF1A is part of the H3/H4 family of histone chaperone proteins corresponding to the anti-silencing function-1 gene in yeast. ASF1A is an important element of the histone donor complex that functions in nucleosome assembly. ASF1A interacts with histones H3 and H4, and functions together with a chromatin assembly factor during DNA replication and repair. Deletion of ASF1A in yeast and Drosophila confers sensitivity to various DNA damaging agents and inhibitors of DNA replication, increases genomic instability and sister chromatid exchange, and activates the DNA damage checkpoint.

Sex-hormone-binding globulin (SHBG) is a beta-globulin which specifically binds steroid hormones; it is involved in the transport of sex steroids in plasma. The main site of SHBG synthesis is assumed to be the hepatocytes. The production of SHBG is regulated by androgen/estrogen balance, thyroid hormones, and dietary factors, among others. The concentration of SHBG is a key factor regulating their distribution between protein-bound and free states. SHBG concentration determination is primarily significant in the evaluation of mild disorders of androgen metabolism and it allows detection of women with hirsutism who are likely to react to estrogen therapy. Testosterone/SHBG-ratios correlate well with both measured and calculated values for free testosterone thus aid to distinguish between subjects with excessive androgen activity and normal individuals. SHBG gene polymorphisms are linked with polycystic ovary syndrome and type 2 diabetes mellitus.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrophobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulate glucose uptake. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severely suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

ASMT is a member of the methyltransferase superfamily. ASMT participates in melatonin biosynthesis. ASMT Expressed in brain, retina and pineal gland, ASMT utilities to catalyze the final reaction in the synthesis of melatonin, particularly the conversion of S-adenosyl-L-methionine and N-acetylserotonin to S-adenosyl-Lhomocysteine and melatonin.

Neurexophilin 1 (NXPH1) is a part of the neurexophilin family which encodes a secreted protein with a variable N terminal domain, an extremely conserved, N-glycosylated central domain, a short linker region, and a cysteine-rich Cterminal domain. NXPH1 shapes a very tight complex with alpha neurexins, a group of proteins which promote adhesion among dendrites and axons.

Tachykinin-3 belongs to the substance P-related tachykinin family. Tachykinins are active peptides that stimulate neurons, induce behavioral responses, are effective vasodilators and secretagogues, and contract (directly or indirectly) many smooth muscles. TAC3 and its receptor are essential switches of regulator of human puberty, regulated by the brain through the release of the GnRH which starts a chain of processes which eventually lead to the production of sex hormones.
During pregnancy, the expression of TAC3 is restricted to the outer syncytiotrophoblast of the placenta, significant concentrations of TAC3 can be identified in plasma as early as week 9, and plasma concentrations of TAC3 are grossly elevated in pregnancy-induced hypertension and pre-eclampsia. Higher Tachykinin-3 concentrations in normotensive pregnant women may be caused by the advanced gestational age and/or the result of a negative interaction of other vasoactive substances. TAC3 has a role in the continuance of high placental blood flow in normal pregnancy.

Periostin is a disulfide linked 90 kDa, 811 amino acid protein originally isolated as a osteoblast-specific factor that functions as a cell adhesion molecule for preosteoblasts and is thought to be involved in osteoblast recruitment, attachment and spreading. Additionally, periostin expression has previously been shown to be significantly increased by both transforming growth factor beta-1(TGFbeta1) and bone morphogenetic protein (BMP-2). OSF-2 has a typical signal sequence, followed by a cysteine-rich domain, a fourfold repeated domain and a C-terminal domain. The fourfold repeated domain of OSF-2 shows homology with the insect protein fasciclin
Periostin mRNA is expressed in the developing mouse embryonic and fetal heart, and that it is localized to the endocardial cushions that ultimately divide the primitive heart tube into a four-chambered heart.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

GNLY is part of the SAPLIP family and is located in the cytotoxic granules of T cells, which are discharged upon antigen stimulation. GNLY is localized in cytotoxic granules of cytotoxic T lymphocytes and natural killer cells, and it has antimicrobial activity against M. tuberculosis and other organisms. GNLY is an antimicrobial protein that kills intracellular pathogens. GNLY is active against a wide range of microbes, including Gram-positive and Gram-negative bacteria, fungi, and parasites. Kills Mycobacterium tuberculosis.