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MMP10 (Matrix Metallopeptidase 10) which is a part of the matrix metalloproteinase (MMP) is activating procollagenase. MMP10 is part of a cluster of MMP genes which localize to chromosome 11q22.3. MMP10 takes part in the breakdown of extracellular matrix in normal physiological processes, like embryonic development, reproduction, and tissue remodeling, as also in disease processes, such as arthritis and metastasis. The majority MMP's are secreted as inactive proproteins that are activated when cleaved by extracellular proteinases. MMP10 encodes an enzyme which degrades proteoglycans and fibronectin.

Agouti-related protein is an endogenous antagonist of hypothalamic alpha-melanocortin receptors MC3R and MC4R with potent orexigenic activity. Although a complete deletion of the AGRP gene does not produce any significant metabolic phenotypes, reduction in AGRP expression by RNA interference is associated with increased metabolic rate along with reduced weight gain. In hypothalamus, it is produced by neurons in the medial portion of arcuate nucleus, which produce also the potent orexigenic peptide Neuropeptide Y (NP-Y). Another site of central AGRP production is the hypothalamic nucleus. AGRP encompasses 132 amino acid residues and its alpha-melanocortin inhibiting activity results in a 34 amino acid cystine knot domain within the C-terminal (87-132) portion of the protein. Both AGRP and NP-Y expression was shown to be suppressed by leptin. Central administration of AGRP induces hyperphagia and increased gain in body weight in rodents, but may also exert metabolic effects even when hyperphagia is prevented. In the absence of hyperphagia, intracerebralventricular administration of AGRP caused significant increases in plasma leptin and insulin concentrations (twofold and 1.5-fold, respectively) and fat pad mass.
In the periphery, AGRP mRNA was found in adrenal glands, lung, testis, ovary, skeletal muscle and adipose tissue in humans or rodents. In the adrenals, it was shown that AGRP antagonizes glucosteroid production mediated by MC4R. AGRP could then modulate locally the functions of some peripheral tissues such as adrenals.
In human and rat serum, detectable levels of AGRP-like activity were reported in the lower picogram range. The serum AGRP levels were elevated in obese humans compared to lean controls and increased with fasting in rats.

Hypoxia-inducible factor-1 (HIF-1), identified as one of the transcription factors, has been found to play an essential role in cellular and systemic oxygen homeostasis. HIF-1 is a heterodimer composed of HIF-1b subunit and one of three subunits (Hif-1a, Hif-2 (or Hif-3)). The activation of Hif-1 (is closely associated with a variety of tumors and oncogenic pathways. Hif-1 (consists of DNA binding domain (DBD domain), Dimerization domain and C-terminal regulatory domains, including two transactivation domains (TAD), an oxygen-dependent degradation (ODD) domain, and inhibitory domains. Under hypoxic conditions HIF1A activates the transcription of more than 40 genes, including, erythropoietin, glucose transporters, glycolytic enzymes, VEGF, and other genes whose protein products increase oxygen delivery or facilitate metabolic adaptation to hypoxia. HIF-1A also plays a crucial role in embryonic vascularization, tumor angiogenesis and pathophysiology of ischemic disease. It binds to core DNA sequence 5'-[AG]CGTG-3' within the hypoxia response element (HRE) of target gene promoters. Activation involves recruitment of transcriptional coactivators such as CREBPB and EP300. Its activity is improved by interaction with both, NCOA1 or NCOA2. Interaction with redox regulatory protein APEX appears to activate CTAD and potentiates activation by NCOA1 and CREBBP. The induction is under reduced oxygen tension. HIF1A is also induced by a variety of receptor-mediated factors such as growth factors, cytokines, and circulatory factors for example PDGF, EGF, FGF-2, IGF-2, TGF-1 beta, HGF, TNF alpha, IL-1 beta, angiotensin-2 and thrombin. Nevertheless, this induction is less intense than that stimulated by hypoxia.

PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and accelerate the folding of proteins. Cyclophilin-A is a cyclosporin binding-protein and may play a role in cyclosporin A-mediated immunosuppression. Cyclophilin-A can also interact with several HIV proteins, including p55 gag, Vpr, and capsid protein, and has been shown to be necessary for the formation of infectious HIV virions. Multiple pseudogenes that map to different chromosomes have been reported.

CYP2E1, also known as Cytochrome P450 2E1 belongs to the cytochrome P450 mixed-function oxidase system which is involved in the metabolism of xenobiotics in the body. While CYP2E1 is implicated in the oxidative metabolism of small range substrates, commonly small polar molecules, there are many significant drug interactions which are mediated by CYP2E1.

Cytohesin-interacting protein, also known as CYTIP contains 2 leucine zipper domains as well as a putative C-terminal nuclear targeting signal. However, CYTIP does not contain any hydrophobic regions. In addition, CYTIP is expressed weakly in resting NK and T cells. It also modulates the activation of ARF genes by CYTH1.

SEMG1 is the predominant protein in semen. The secreted protein takes part in the formation of a gel matrix which encases ejaculated spermatozoa. The prostate-specific antigen (PSA) protease processes SEMG1 into smaller peptides, with each possibly having a separate function. The proteolysis process breaks down the gel matrix and allows the spermatozoa to shift more freely. 2 transcript variants encoding different isoforms have been found for SEMG1.

High Mobility Group Nucleosomal Binding Domain 3 (HMGN3), binds thyroid hormone receptor beta, however it occurs only in the presence of thyroid hormone. Thyroid hormone receptors are hormone-dependent transcription factors which regulate expression of a variety of particular target genes. HMGN3 is considered to reduce the compactness of the chromatin fiber in nucleosomes, in that way enhancing transcription from chromatin templates.

Heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) is a member of the A/B subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). HNRNPA1 is involved in the packing of pre-mRNA into hnRNP particles, transport of poly(A) mRNA from the nucleus to the cytoplasm and may control splice site selection. The HNRNPA1 protein may also have a role in HCV RNA replication. In addition, HNRNPA1 is believed to have a key role in the formation of specific myometrial protein species in parturition.
The hnRNP proteins have distinctive nucleic acid binding properties. HNRNPA1 has 2 repeats of quasi-RRM domains that bind to RNAs. HNRNPA1 is one of the most copious core proteins of hnRNP complexes and it is restricted to the nucleoplasm. The HNRNPA1 protein, along with other hnRNP proteins, is exported from the nucleus, most likely bound to mRNA, and is immediately re-imported. The M9 domain of HNRNPA1 functions as both a nuclear localization and nuclear export signal.

HPRT1 has a main part in the generation of purine nucleotides through the purine salvage pathway. HPRT1 primarily functions to salvage purines from degraded DNA to renewed purine synthesis. Therefore, it performs as a catalyst in the reaction between guanine and phosphoribosyl pyrophosphate to form GMP.

NAP1L1 is a member of the nucleosome assembly protein (NAP) family. NAP1L1 protein plays a part in DNA replication, modulating chromatin formation and regulation of cell proliferation.

The transcription of heat-shock genes is rapidly induced after temperature stress in response to environmental changes, and it is also involved in oogenesis, spermatogenesis, and placental development. Hsp90, is a major repressor of HSF1 gene. HSF1 is known for its participation in heat shock response. HSF1 protein regulates the transcription of hundreds of targets, such as genes involved in protein folding, detoxification, energy generation, carbohydrate metabolism, and cell wall organization.
HSF1 binds to MTA1 in vitro & in breast carcinoma. Suppression of estrogen-dependent transcription may contribute to role of HSF1 in cancer.
Human cancer lines of diverse origins express higher dependence on HSF1 function to maintain proliferation and survival than their non-transformed counterparts.
HSF1 induces anticoagulation and relaxation factors in vascular endothelial cells and could therefore be used to treat cardiovascular disease. HSF1 is directly involved in the regulation of HO1 having an anti-oxidative role.
NF-kappaB and HSF1 are systemically activated in human acute pancreatitis.
HSF1 activation protects against severity of pancreatitis.
HSF is a vital transcription factor which plays a role in up-regulation of VDUP1 expression through stresses such as elevated density and serum deprivation cultures.

NCALD belongs to the neuronal calcium sensor (NCS) family. NCALD is cytosolic at inactive calcium levels; but, high intracellular calcium levels induce a conformational transformation which exposes the myristoyl group, causing protein association with membranes and partial co-localization with the perinuclear trans-golgi network. NCALD protein is a regulator of signal transduction by G protein-coupled receptor.

HSPA6 is a distinctive member of the human Hsp70 chaperone that takes part in cellular processes such as protein trafficking, folding, and prevention of aggregation. HSPA6 is strictly stress-inducible, having little or no basal expression levels in most cells. HSPA6 and HSP72 are are involved in cell survival of proteotoxic stress.

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.

HTATIP2 is part of the short-chain dehydrogenases/reductases (SDR) family which acts as a tumor suppressor in metabolic suppression, inhibition of angiogenesis and induces the expression of apoptosis related genes Bad and Siva. HTATIP2 cooperates with the activation domain of HIV-1 TAT and enhances its transcription by phosphorylating RNA polymerase II (Pol II). Defects in HTATIP2 are related with hepatocellular carcinomas and apoptotic resistant tumor cells, implicating a probable use for HTATIP2 in antitumor therapy.

DR1 is a phosphoprotein that inhibits both basal and activated levels of transcription. DR1 is phosphorylated in vivo which affects its interaction with TBP. DR1 has a histone fold motif at the amino terminus, a TBP-binding domain, and a glutamine- and alanine-rich region. By selectively repressing polymerases II and III, DR1 alters the physiological balance of transcriptional output in favor of polymerase I.

Homeobox protein SIX1 (SIX1) belongs to the SIX gene family. SIX1 is characterized by a divergent DNA-binding homeodomain and an upstream SIX domain, which is involved both in determining DNA-binding specificity and in mediating protein-protein interactions. SIX1 has a role in vertebrate and insect development or in the maintenance of the differentiated state of tissues.

SKP1 is a F-box enzyme which functions as a substrate recognition component of the SCF ubiquitin ligase complex which controls the ubiquitination of proteins involved in cell cycle progression, signal transduction and transcription. SKP1 binds to proteins containing an F-box motif, such as cyclin F, S-phase kinase-associated protein 2, and other regulatory proteins involved in ubiquitin dependent proteolysis. SKP1 takes part in the control of beta-catenin levels and the activity of beta-catenin dependent TCF transcription factors. SKP1 serves as an adapter that links the F-box protein to CUL1 in the SCF complex.

Inhibitor of DNA Binding 2 (ID2) is a part of the inhibitor of DNA binding family, whose members are transcriptional regulators that contain a helix-loop-helix (HLH) domain but not a basic domain. Members of the ID family inhibit the functions of basic helix-loop-helix transcription factors in a dominant-negative way by suppressing their heterodimerization partners through the HLH domains. ID2 play a role in negatively regulating cell differentiation and may be an inhibitor of tissue-specific gene expression.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

Syntaxin-1, synaptobrevin, and SNAP25 cooperate to form the SNARE complex, which is needed for synaptic vesicle docking and fusion SNPH is a neuron-specific protein originally characterized as a binding partner of syntaxin-1. SNPH participates with SNAP25 for the binding to Syntaxin-1 and prevents the construction of the SNARE core complex, thus manageling free syntaxin-1 availability for the assembly of the SNARE complex and potentially regulating synaptic vesicle exocytosis. Expression Syntaphilin appears to be brain-specific. SNPH is an inhibitor of both SNARE-based fusion and dynamin-mediated endocytosis.

ATPase inhibitory factor 1 (ATPIF1) attaches to the C-terminal region of a beta subunit of the F1-ATPase at low pH values and, through interference of the beta and gamma subunit interaction, ATPIF1 controls the activity of the F1 (the hydrophilic catalytic core), F0 (the membrane embedded protein channel) ATPase. ATPIF1 overexpression in a number of human carcinomas additionally reinforces its participation in oncogenesis and offers insight into the transformed metabolism of cancer cells, including the reprogramming of energy metabolism in relation to glycolysis. Endogenous F1F(o)-ATPase inhibitor curbing ATP depletion when the mitochondrial membrane potential drops below a threshold and the F1F(o)-ATP synthase begins hydrolyzing ATP to pump protons out of the mitochondrial matrix.

EIF1AX is an important eukaryotic translation initiation factor. EIF1AX is essential for the binding of the 43S complex (a 40S subunit, eIF2/GTP/Met-tRNAi and eIF3) to the 5'' end of capped RNA. EIF1AP1 is needed for maximal rate of protein biosynthesis. EIF1AX increases ribosome dissociation into subunits and stabilizes the binding of the initiator Met-tRNA (I) to 40 S ribosomal subunits.