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A 16kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.

Myoglobin is a member of the globin superfamily and can be found in skeletal and cardiac muscles. It is a haemoprotein that contributs to intracellular oxygen storage and transcellular facilitated diffusion of oxygen. Myoglobin has a single-chain globular structure of 153 amino acids, containing a heme prosthetic group (iron-containing porphyrin) in the core around which the remaining apoprotein folds. Myoglobin has 8 alpha helices and a hydrophobic core. Myoglobin’s molecular weight is 16.7 kDa, and it is the primary oxygen-carrying pigment of muscle tissues. The binding of oxygen in myoglobin is different from the cooperative oxygen binding in hemoglobin, since positive collaboration is a property of multimeric/oligomeric proteins only. Instead, the binding of oxygen by myoglobin is uninfluenced by the oxygen pressure in the surrounding tissue. Myoglobin is frequently referred to as having an "instant binding tenacity" to oxygen given its hyperbolic oxygen dissociation curve. Different organisms are able to hold their breaths longer due to high concentrations of myoglobin in their muscle cells. Myoglobin is responsible for the pigments that make meat red. The color of the meat is partly determined by the charge of the iron atom in myoglobin and the oxygen attached to it. Myoglobin is found in Type I muscle, Type II A and Type II B, but it is mostly deemed that myoglobin is not found in smooth muscle. Myoglobin is discharged from damaged muscle tissue (rhabdomyolysis), which contains very high concentrations of myoglobin. Even though the released myoglobin is filtered by the kidneys, it is toxic to the renal tubular epithelium and thus may cause acute renal failure.

CITED2 is a significant transcriptional cofactor that takes part in multiple organ development. CITED2 is a cAMP-responsive element-binding protein (CBP)/p300 interacting transcriptional modulator and a negative regulator for HIF1A through its competitive binding with HIF1A to CBP/p300. CITED2 is essential for mouse fetal liver hematopoiesis and is necessary for the appropriate formation of the hyaloid vasculature and for lens morphogenesis. CITED2 is a coactivator of HNF4alpha and necessary for liver development. CITED2 is a coactivator of PPAR-alpha and both participate in signaling cascades of hypoxic response and angiogenesis.

Ebolavirus (EVD) belongs to the Filoviridae family of proteins which is comprised of a single-strand, non-infectious RNA genome. EVD genome is about 19,000 base pairs long and covers 7 genes in the order 3'-UTR-NP-VP35-VP40-GP-VP30-VP24-L-5'-UTR. There are 4 different ebolaviruses such as: Zaire (EBO-Z), Sudan (EBO-S), Cote d’Ivoire (EBO-CI) and Reston (EBO-R) that differ in amino acid sequence and location of where the gene overlaps. Similar to filoviruses and ebolavirions, EVD is a filamentous element that could appear in 3 forms: shepherd's crook, U shape or a 6 shape. Ebolaviruses may be coiled, toroid, or branched. Most ebolavirions are 80nm wideand 14,000nm long.

MICA (MHC class I chain-related gene A) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICB, shares 85% amino acid identity with MICA. These proteins are distantly related to the MHC class I proteins. They possess three extracellular Ig-like domains, but they have no capacity to bind peptide or interact with ?2-microglobulin. The genes encoding these proteins are found within the Major Histocompatibility Complex on human chromosome 6. The MICA locus is highly polymorphic with more than 50 recognized human alleles. MICA is absent from most cells but is frequently expressed in epithelial tumors and can be induced by bacterial and viral infections. MICA is a ligand for human NKG2D, an activating receptor expressed on NK cells, NKT cells,gammadelta T cells, and CD8+beta T cells. Recognition of MICA by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA recognition is involved in tumor surveillance, viral infections, and autoimmune diseases.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

Coactosin-like protein (COTL1) is one of the numerous actin-binding proteins which regulate the actin cytoskeleton. COTL1 binds F-actin, it also interacts with 5-lipoxygenase, which is the first committed enzyme in leukotriene biosynthesis. COTL1 binds to F-actin in a calcium-independent way and has no direct effect on actin depolymerization.

Crystallin Zeta, also known as CRYZ, Binds NADP and participates in a one-electron transfer process. CRYZ takes part in the detoxification of xenobiotics and Interacts with (AU)-rich elements (ARE) in the 3'-UTR of target mRNA species. CRYZ improves the mRNA coding for BCL2.

Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

Zinc Finger HIT-Type Containing 1 (ZNHIT1) is a member of the ZNHIT1 family and contains 1 HIT-type zinc finger. The ZNHIT1 protein is induced by DNA damage and appears to have a role in p53-mediated apoptosis induction. ZNHIT1 interacts with MAPK11 and MAPK14 and is a component of the chromatin-remodeling SRCAP complex composed of at least SRCAP, DMAP1, RUVBL1, RUVBL2, ACTL6A, YEATS4, ACTR6 and ZNHIT1. ZNHIT1 binds to NR1D2 and discharges it of its inhibitory effect on the transcription of APOC3 without affecting its DNA-binding activity.

RELM-beta (Resistin-Like Molecule-beta) is a member of a recently identified family of secreted proteins containing a conserved cystein-rich C-terminus. The RELM family consists of resistin (also called FIZZ3), RELM-alfa (FIZZ1), RELM-beta (FIZZ2) and RELM-gamma. Only resisistin and RELM-beta were found in humans whereas all four RELM family members were identified in rodents.
RELM-beta appears to be produced as a homodimer exclusively by intestinal goblet cells and can be found in high quantities in stool. Remarkably, stool of germ-free mice displaying sterile intestinal tract does not contain RELM-beta until bacterial colonization takes place after pathogen-free mice entered natural environment. Some, but not all, colon carcinoma cell lines secrete RELM-beta into the cell culture supernatant.
The physiological function of RELM-beta is not known. High doses of recombinant RELM-beta showed hyperglycemic effects including lowered glucose disposal and increased hepatic glucose production in mice.

CD47, functions in cell adhesions by performing as an adhesion receptor for THBS1 on platelets, furthermore CD47 plays a role in the modulation of integrins. In addition, CD47 takes a vital part in memory formation as well as synaptic plasticity in the hippocampus. Receptor for SIRPA avoids maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells. CD47 prevents premature elimination of red blood cells, and it is also implicated in membrane permeability changes induced following virus 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.

SH3-Domain GRB2-Like 3, also known as SH3GL3, is a part of the endophilin family. SH3GL3 contains 1 BAR domain and 1 SH3 domain and takes part in endocytosis. SH3GL3 is a protein coding gene which drafts proteins with high curvature to membranes.

Mature T-Cell Proliferation 1, also known as MTCP1 was recognized by involvement in some t(X;14) translocations linked with mature T-cellproliferations. This region has a complex gene structure, with a common promoter and 5' exon spliced to two dissimilar sets of 3' exons which encode two different proteins. It represents the upstream 13 kDa protein which belongs to the TCL1 family. In addition, MTCP1 enhances the phosphorylation and activation of AKT1 and AKT2. MTCP1 is involved in leukemogenesis.Among the diseases associated with MTCP1 are queensland tick typhus, and african tick-bite fever.

SNURF is an extremely basic protein restricted to the nucleus. The evolutionarily reserved open reading frame is located on a bicistronic transcript which has a downstream ORF encoding the small nuclear ribonucleoprotein polypeptide N. The first three exons of the transcript are exploited by the upstream coding region which is known as an imprinting center. The full-length nature of these transcripts is yet to be determined but multiple transcription initiation sites have been identified and large scale alternative splicing takes place in the 5' untranslated region. An alternate exon which substitutes for exon 4 and leads to a truncated, monocistronic transcript was identified. Deletion or alternative splicing produced by a translocation event in the 5' UTR or coding region of this gene results in Prader-Willi syndrome or Angelman syndrome because of parental imprint switch failure.

Tri a 14.0101 is a non-specific lipid transfer protein and a major wheat allergen. Those who are sensitive to this allergen may have baker’s asthma, a frequent occupational allergic disease caused mainly by inhalation of cereal flour, especially wheat flour. Tri a 14.0101 consists of 4 helical fragments and irregular C-terminal regions which are highly stable to heat treatment and proteolytic attack.

Secernin 1 (SCRN1) which is a member of the peptidase C69 family, regulates exocytosis in mast cells. SCRN1 increases both the level of secretion and the sensitivity of mast cells to stimulation with calcium.

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.

Junctional Adhesion Molecule 2 (JAM2) is a member of the immunoglobulin superfamily, and the junctional adhesion molecule (JAM) family. JAM2 is a type I membrane protein which is localized at the tight junctions of both epithelial and endothelial cells. JAM2 functions as an adhesive ligand for interacting with various immune cell types, and may have a role in lymphocyte homing to secondary lymphoid organs.

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.

MAX protein is part of the basic helix-loop-helix leucine zipper (bHLHZ) family of transcription factors. MAX forms homodimers and heterodimers with Mad, Mxi1 and Myc. Myc is an oncoprotein implicated in cell proliferation, differentiation and apoptosis. The homodimers and heterodimers compete for a common DNA target site (the E box) and rearrangement among these dimer forms offers a complex system of transcriptional regulation. In contrast to Myc, which is exceedingly regulated throughout progression during the cell cycle, Max is very stable and is much more abundant than Myc.

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.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 epsilon, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of insulin sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.