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GH-releasing peptides (GHRPs) are synthetic peptides that like GHRH act directly on pituitary somatotrophs to stimulate GH release. Growth hormone (GH) release is stimulated by a variety of synthetic secretagogues, of which growth hormone-releasing hexapeptide (GHRP-6) has been most thoroughly studied; it is thought to have actions at both pituitary and hypothalamic site.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

SAM Domain SH3 Domain and Nuclear Localization Signal 1 (SAMSN1) is a member of a known adaptors and scaffold proteins containing SH3 and SAM (sterile alpha motif) domains. SAMSN1 is a negative regulator of B-cell activation and is down-regulates cell proliferation. SAMSN1 is up-regulated by IL-4 in activated B cells and expressed mainly in dendritic cells. SAMSN1 owns a function which is similar to other adaptor proteins that link signaling molecules in signal transduction cascades.

HP-NAP protects DNA from oxidative damage by sequestering intracellular Fe2+ ion and storing it in the form of Fe3+ oxyhydroxide mineral. One hydrogen peroxide oxidizes two Fe2+ ions, thus preventing hydroxyl radical production by the Fenton reaction. HP-NAP is necessary for the survival in the presence of oxidative stress. Dps is also a virulence factor which activates neutrophils, mast cells and monocytes. HP-NAP binds to neutrophil-glycosphingolipids and to sulfated carbohydrates on mucin. HP-NAP might play a part in the accumulation of neutrophils and monocytes at the site of infection. HP-NAP induces superoxide anion generation, adhesion and chemotaxis of neutrophils, via a pertussis toxin-sensitive pathway involving MAP kinases.

The peroxisome proliferator activated receptors (PPARs) are ligandactivated transcription factors within the nuclear receptor superfamily, which play important roles in adipogenesis, glucose homeostasis andinflammation. Three different isotypes can be distinguished; alpha, beta and gamma. PPARg, is mainly expressed in adipose tissue and to lesser extent in colon, the immune system and the retina. Whereas PPARg operates in the catabolism of fatty acids in the liver, PPARg influences the storage of fatty acids in the adipose tissue and plays a role in adipocyte differentiation. PPARg binds to DNA as a heterodimer with retinoid X receptor (RXR), activating expression of target genes after binding ligand.

Adiponectin is a protein exclusively secreted from adipose tissue. In the circulation, adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (LMW, also called trimer) forms. Different oligomeric complex of adiponectin activates different signaling pathways and exerts distinct functions.

Centromere protein P (CENPP) is component of the CENPA-CAD (nucleosome distal) complex, which is a complex recruited to centromeres and involved in assembly of kinetochore proteins, mitotic progression and chromosome segregation. CENPP protein is involved in incorporation of newly synthesized CENPA into centromeres by way of its interaction with the CENPA-NAC complex.

Ciliary Neurotrophic Factor Receptor, also known as CNTFR is a member of the type I cytokine receptor family. CNTFR binds to CNTF. The alpha subunit provides the receptor specificity. Sole nucleotide polymorphisms in CNTFR has been associated with variations in muscle strength, in addition to early onset of eating disorders.

COP9 Constitutive Photomorphogenic 6 (COPS6) is a member of the translation initiation factor 3 (eIF3) superfamily,peptidase M67A family and CSN6 subfamily. COPS6 is one of 8 subunits of COP9 signalosome,a highly conserved protein complex which functions as an significant regulator in multiple signaling pathways. COP9's structure and function of signalosome is similar to 19S regulatory particle of 26S proteasome. COP9 signalosome can interact with SCF-type E3 ubiquitin ligases and act as a positive regulator of E3 ubiquitin ligases.COP9 takes part in the regulation of cell cycle and likely to be a cellular cofactor for HIV-1 accessory gene product Vpr.

TNFAIP3-interacting protein 1 (TNIP1) interacts with zinc finger protein A20/TNFAIP3 and inhibits TNF-induced NF-kappa-B-dependent gene expression by interfering with a RIP- or TRAF2-mediated transactivation signal. Furthermore, TNIP1 interacts with HIV-1 matrix protein and is packaged into virions and its overexpression can inhibit viral replication. TNIP1 can regulate matrix nuclear localization, both nuclear import of Preintegration complex (PIC) and export of GAG polyprotein and viral genomic RNA during virion production.

NAPA is part of the SNAP (Soluble NSF Attachment Protein) family. SNAPs, acting together with SNAREs (SNAP receptors) and the N-ethylmaleimide-sensitive fusion protein (NSF), are necessary for the fusion of transport vesicles to their objective membranes in synaptic transmission, intra-Golgi transport, endosome-to-endosome fusion and transcytotic vesicles-to-plasma membrane transport. NAPA is in charge of the binding of NSF and therefore the formation of a 20S fusion particle.

The NUP210 complex is a immense structure which spreads through the nuclear envelope, forming a doorway which regulates the flow of macromolecules between the nucleus and the cytoplasm. Nucleoporins are the core components of the nuclear pore complex in eukaryotic cells. NUP210 is a membrane-spanning glycoprotein and is a major component of the nuclear pore complex.

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.

GABARAPL2 takes part in intra Golgi traffic and modulates intra Golgi transport by coupling between NSF activity and SNAREs activation. GABARAPL2 first stimulates the ATPase activity of NSF which in turn stimulates the association with GOSR1.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

Serine/arginine-rich splicing factor 1 (SFRS1) belongs to the arginine/serine-rich splicing factor protein family, and functions in both constitutive and alternative pre-mRNA splicing. SFRS1 binds to pre-mRNA transcripts and components of the spliceosome, and can either initiate or inhibit splicing depending on the position of the pre-mRNA binding site. The ability of SFRS1 to activate splicing is controlled by phosphorylation and interactions with other splicing factor associated proteins.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

SUGT1 is homolog to yeast protein SGT1, a regulator of the cell cycle which is vital for G1/S and G2/M transitions. SUGT1 holds a CS domain, a SGS domain, a p23 domain and three tetratricopeptide repeats (TPR). SUGT1 protein associates with Skp1 p19 and CUL-1, subunits of the SCF ubiquitin ligase complex, and is believed to take a part in protein degradation. Furthermore, SUGT1 is essential for the kinetochores assembly, and has a role as a co-chaperone for HSP90.

Polymerase II Polypeptide D (POLR2D) is a member of the eukaryotic RPB4 RNA polymerase subunit family. POLR2D is the fourth largest subunit of RNA polymerase II. Pol II is the main element of the basal RNA polymerase II transcription machinery. polymerase is responsible forsynthesizing messenger RNA in eukaryotes. In yeast, POLR2D subunit is connected with the polymeraseunder suboptimal growth conditions and might have a stress protective role. POLR2D catalyzes the transcription of DNA into RNA by the 4 ribonucleoside triphosphates as substrates.

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).

Regulation of nuclear pre-mRNA domain-containing protein 1B (RPRD1B) interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and participates in dephosphorylation of the CTD. RPRD1B stimulates binding of RNA polymerase II to the CCDN1 promoter and to the termination region before the poly-A site but decreases its binding after the poly-A site. RPRD1B inhibits RNA polymerase II from reading through the 3' end termination site and may allow it to be drafted back to the promoter through promotion of the formation of a chromatin loop. In addition, RPRD1B enhances the transcription of several other cell cycle-related genes including CDK2, CDK4, CDK6 and cyclin-E but not CDKN1A, CDKN1B or cyclin-A. RPRD1B also promotes cell proliferation.

CRP is an acute phase protein that correlates with inflammatory disease and is synthesized by hepatocytes during the acute phase response by certain cytokines (IL-1 and TNF Alpha and Beta). CRP levels increase dramatically and serve as a useful marker of inflammation in such conditions as bacterial infection, rheumatoid arthritis, viral infections, transplantation rejection, meningitis, myocardial infarction, septicemia, osteomyelitis and others. CRP is also highly correlated to Serum Amyloid A levels.

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.