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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 hydrofobic 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.
Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. Steppan et al. have suggested that resistin suppresses the ability 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 severly 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.

Ribosomal Protein L5, also known as RPL5 is a part of the ribosomal protein L18P family. RPL5 which binds 5S RNA is necessary for rRNA maturation and structure of the 60S ribosomal subunits.

GH-releasing peptides (GHRPs) are synthetic peptides that like GHRH act directly on pituitary somatotrophs to stimulate GH release. GHRP-2, an investigational drug, is one of the most potent members of the GHRP family. It has been shown to be effective in adults via the oral and intranasal as well as the iv route of administration.

Lumican also known as LUM is a part of the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore, we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair.

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.

AKR1C1 transfers progesterone to its inactive state or in other words catalyzes the reaction of 20-alpha-hydroxy progesterone (20-alpha-OHP). In the liver and intestine. AKR1C1 transfers bile and monitors the intrahepatic bile acid concentration though it has a low bile-binding ability. AKR1C1 participates in myelin formation. AKR1C1 is part of the aldo/keto reductase superfamily, which has over 40 known enzymes which catalyze the conversion of aldehydes and ketones to their corresponding alcohols by utilizing NADH and/or NADPH as cofactors thus display overlapping but distinct substrate specificity.

Histidine NADH Dehydrogenase Fe-S Protein 5 (NDUFS5) belongs to the NADH dehydrogenase (ubiquinone) iron-sulfur protein family. NDUFS5 is a subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I), which doesn’t take part in catalysis. Complex I is transferring the electrons from NADH to the respiratory chain.

EFNA3 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors include thelargest subfamily of receptor protein-tyrosine kinases which have been implicated in mediating developmental events, especially in the nervous system and in erythropoiesis. Ephrins are divided into the ephrin-A (EFNA) class and the ephrin-B (EFNB) class, based on their structures and sequence relationships. The Ephrins from the EFNA class are anchored to the membrane by aglycosylphosphatidylinositol linkage, while the others from the EFNB class are transmembrane proteins.

Ephrin-B2 belongs to the ephrin (EPH) family. The ephrins and EPH-related receptors contain the largest subfamily of receptor protein-tyrosine kinases and have been associated with mediating developmental events, particularly in the nervous system and in erythropoiesis. Based upon their structures and sequence relationships, ephrins are allocated into the ephrin-A (EFNA) class, which are anchored to the membrane by a glycosylphosphatidylinositol linkage, and the ephrin-B (EFNB) class, which are transmembrane proteins. Ephrin-B2 binds to the EPHB4 and EPHA3 receptors.

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.

ST13 is an adaptor protein (co-chaperone) that mediates the association of HSP70 & HSP90 and appears in early receptor complexes. ST13 plays a role in the assembly process of glucocorticoid receptor, which requires the assistance of multiple molecular chaperones. The expression of ST13 is downregulated in colorectal carcinoma tissue signifying that is candidate tumor suppressor gene. Through common binding to both Hsp70 and Hsp90, ST13 functions as an adaptor that can integrate Hsp70 and Hsp90 interactions. The expression of ST13 decreases in colorectal cancer tissue compared with that in adjacent normal tissue. ST13 is mostly expressed in colorectal epithelia and adenocarcinoma cells. ST13 functions to promote the efficiency of glucocorticoid receptor maturation in cells. The expression levels of the ST13 gene were significantly decreased in primary tumors compared with adjacent mucosa.

TIE-1 (tyrosine kinase with Ig and EGF homology domains 1) and TIE-2/Tek comprise a receptor tyrosine kinase (RTK) subfamily with unique structural characteristics: two immunoglobulin-like domains flanking three epidermal growth factor (EGF)-like domains and followed by three fibronectin type III-like repeats in the extracellular region and a split tyrosine kinase domain in the cytoplasmic region. These receptors are expressed primarily on endothelial and hematopoietic progenitor cells and play critical roles in angiogenesis, vasculogenesis and hematopoiesis. Human TIE-1 cDNA encodes a 1122 amino acid (aa) residue precursor protein with an 18 residue putative signal peptide, a 726 residue extracellular domain and a 353 residue cytoplasmic domain. Two ligands, angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2), which bind TIE-2 with high-affinity have been identified. Ang2 has been reported to act as an antagonist for Ang1. Mice engineered to overexpress Ang2 or to lack Ang1 or Tie-1 display similar angiogenic defects.

Kallikrein-10 (KLK10) is one of the 15 kallikrein subfamily members located in a cluster on chromosome 19. Kallikreins are a subgroup of serine proteases having various physiological functions. KLK10 is secreted and has a role in suppression of tumorigenesis in breast and prostate cancers.

CKS1B protein which binds to the catalytic subunit of cyclin dependent kinases is vital for their biological function. The CKS1B mRNA is expressed in HeLa cells during the course of cell cycle in several forms which suggests that the encoded protein has a particular function. Two transcript variants were identified for this gene however it seems that only one of them encodes a protein.

CKS2 protein binds to the catalytic subunit of the cyclin dependent kinases and is necessary for their biological function. The CKS2 mRNA is expressed in various patterns through the cell cycle in HeLa cells, which shows spcific role for the encoded protein. CKS2 (CDC28) Protein kinase 2 binds to the catalytic subunit of cyclin-dependent kinases and has thus in involved in cell cycle regulation. CKS2 is required for the first metaphase/anaphase transition during the meiosis. An increase in expression of CKS2 protects the cells from apoptosis. CKS2 is essential during early embryogenesis and cell cycle progression in somatic cells.

Gametocyte Specific Factor 1 (GTSF1) is a member of the UPF0224 (FAM112) family and contains 1 CHHC-type zinc finger. A key paralog of the GTSF1 gene is GTSF1L.

COP9 signalosome complex subunit 8 isoform 1 (COPS8) is one of the 8 subunits of COP9 signalosome, which is a much conserved protein complex that functions as an imperative regulator in multiple signaling pathways. The structure and function of COP9 signalosome is analogous to that of the 19S regulatory particle of 26S proteasome. COP9 signalosome interacts with SCF-type E3 ubiquitin ligases and acts as a positive regulator of E3 ubiquitin ligases.

RALY belongs to the heterogeneous nuclear ribonucleoprotein (hnRNP) gene family. RALY takes part in pre-mRNA splicing and also in embryonic development. Moreover, alternate splicing results in multiple transcript variants have been found for RALY.

Regulator of G-protein signaling 21 (RGS21) belongs to the RGS family and regulatory molecules which act as GTPase activating proteins for G alpha subunits of heterotrimeric G proteins. The RGS21 protein inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits thus driving them into their inactive GDP-bound form.

Ring Finger Protein 7, also known as RNF7, is an extremely conserved ring finger protein. RNF7 is a vital subunit of SKP1-cullin/CDC53-F box protein ubiquitin ligases that are a part of the protein degradation machinery important for cell cycle progression and signal transduction. RNF7 is a substrate of casein kinase II (CSNK2A1/CKII) and also interacts with it. The phosphorylation of RNF7 by CSNK2A1 promotes the degradation of IkappaBalpha (CHUK/IKK-alpha/IKBKA) and p27Kip1(CDKN1B).

Ribosomal Protein S6 Kinase Beta-1 Isoform A or RPS6KB1 is type of serine/threonine kinas. The protein effects on the PIP3 and phosphoinositide-dependent kinase-1 as part of the PI3 kinase pathway. Protein synthesis is induced by Phosphorylation of S6 in the ribosome. It was shown that phosphorylation of p70S6K at threonine 389 acts as mTOR activation indication and corresponded along with the inhibition of autophagy in different cases, nonetheless new studies has shown that the p70S6K activity has a constructive and increasing affect of autophagy.

LAMTOR4 is implicated in amino acid sensing and activation of mTORC1, which is a signaling complex promoting cell growth in response to growth factors, energy levels, and amino acids. LAMTOR4 is activated by amino acids via a mechanism which involves the lysosomal V-ATPase, the Ragulator functions as a guanine nucleotide exchange factor activating the small GTPases Rag. Activated Ragulator and Rag GTPases both function as a scaffold recruiting mTORC1 to lysosomes where it is sequentially activated.

RAD51D is a member of the RAD51 protein family whose members are extremely similar to bacterial RecA and Saccharomyces cerevisiae Rad51. RAD51 protein family members take part in the homologous recombination and repair of DNA. RAD51D forms a complex with several other members of the RAD51 family which catalyzes homologous pairing between single- and double-stranded DNA, and participates in the early stage of recombinational repair of DNA.

CRK belongs to the signaling adapter protein family which binds to several tyrosine-phosphorylated proteins. CRK is involved in many cellular processes such as apoptosis, proliferation, and differentiation. CRK has a modular domain architecture consisting of an SH2 followed by two SH3 domains (src-homology domains). The N-terminal SH2 domain of the CRK protein functions as a positive regulator of transformation whereas the C-terminal SH3 domain functions as a negative regulator of transformation.