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SAA1 protein is an acute phase apolipoprotein reactant which is produced mostly by hepatocytes and under regulation of inflammatory cytokines. SAA1 (Serum amyloid A1) protein is produced mainly in the liver and circulates in low levels in the blood. The SAA1 seems to have a role in the immune system. SAA1 protein levels increase in the blood and other tissues under conditions of inflammation. SAA1 may facilitate the repair of injured tissues; it also acts as an antibacterial agent, and signals the migration of germ-fighting cells to sites of infection. SAA1 also functions as an apolipoprotein of the HDL complex.
Elevated levels of SAA1 ultimately affect secondary amyloidosis, extracellular amassing of amyloid fibrils, resulting from a circulating precursor, in a variety of tissues and organs. The most widespread type of amyloidosis appears secondary to chronic inflammatory disease, mainly rheumatoid arthritis. The SAA1 cleavage product a designated amyloid protein A is deposited systemically as amyloid in vital organs such as the liver, spleen, and kidneys in chronic inflammatory diseases patients. These deposits are extremely insoluble and resistant to proteolysis; they disrupt tissue structure and compromise performance.

ECHS1 is part of the hydratase/isomerase superfamily. ECHS1 is localized in the mitochondrial matrix and Expressed in muscle, liver and fibroblasts, with low expression in kidney and spleen, ECHS1 exists as a homohexamer that takes part in the second phase of the mitochondrial fatty acid β-oxidation pathway.

EFNB1 is a member of the Eph family. The cell-surface proteins Ephrins split into two groups, ephrin-A and ephrin-B, based on their structure and function and perform as ligands for Eph receptors. The transmembrane EFNB1 proteins have conserved cytoplasmic tyrosine residues that are phosphorylated upon interaction with an EphB receptor. In addition, EFNB1 transduces outside-in signals by C-terminal protein interfaces which influence integrin-mediated cell attachment and migration.

Hepatitis A Virus Cellular Receptor 2 (HAVCR2) is a member of the immunoglobulin superfamily. HACVR2 controls macrophage activation. HACVR2 inhibits T-helper type 1 lymphocyte (Th1)-mediated auto- and alloimmune responses and stimulates immunological tolerance.

Caused by one of four closely related virus serotypes of the genus Flavivirus, family Flaviviridae, each serotype is sufficiently different that there is no cross-protection and epidemics caused by multiple serotypes (hyperendemicity) can occur. In cell culture experiments and mice Morpholino antisense oligos have shown specific activity against Dengue virus.

UBE2K belongs to the ubiquitin-conjugating enzymes family which take part in many cellular processes such as selective protein degradation, DNA repair, cell cycle control, and sporulation. In this mechanism, the ATP-coupled activation and subsequent ligation of ubiquitin are catalyzed by separate enzymes functionally linked by ubiquitin carrier protein UBC1. In addition, UBE2K is involved in Alzheimer's disease, Huntington's disease and antigen processing through its interaction with amyloid-?, huntingtin, and MHC-heavy chain proteins.

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.

Integrase is an enzyme produced by the HIV which enables its genetic material to be integrated into the DNA of the infected cell and is a key component in the pre-integration complex. HIV integrase contains 3 domains, an N-terminal HH-CC zinc fingerdomainwhich is partially responsible for multimerization, a central catalytic domain and a C-terminal domain. Both Central catalytic domain and C-terminal domains have been shown to bind both viral and cellular DNA. No crystal structure data exists with Integrase bound to its DNA substrates. HIV-1 integrase functions as a dimeror a tetramer. Additionally, several host cellular proteins interact with integrase and may facilitate the integration process.

Noroviruses are categorized into two groups - group 1 and group 2. Norovirus is a widespread virus which can cause human gastroenteritis, an illness characterized with symptoms such as abdominal pain, diarrhea, vomiting and sickness. In America there are about 20 million causes of infection by Nororvirus, 800 ending in deaths. Worldwide, this virus infects around 267 million people and causes over 200,000 deaths per year. Even though having norovirus is unpleasant, it is seldom dangerous and typically ends in full recovery after few days. The cases resulting in deaths are primarily very young, elderly and immuno-suppressed individuals and people from less developed countries. Norovirus is extremely contagious and is spread from person to person, by infected food or water or polluted surfaces. Outbreaks usually happen from November to April, peaking in January.

The life cycle of Toxoplasma gondii has two phases. The coccidia like takes place only in members of the Felidae family which makes these animals the parasite's primary host. The asexual part of the life cycle can take place in any warm-blooded animal, like other mammals(including felines) and birds. T. gondii constructing daughter scaffolds within the mother cell. In the intermediate hosts (including felines), the parasite invades cells, forming intracellular so-called parasitophorous vacuoles containing bradyzoites, the slowly replicating form of the parasit. Vacuoles form tissue cysts mainly within the muscles and brain. Since they are within cells, the host's immune system does not detect these cysts. Resistance to antibiotics varies, but the cysts are very difficult to eradicate entirely. Within these vacuoles T. gondii propagates by a series of binary fissions until the infected cell eventually bursts and tachyzoites are released. Tachyzoites are the motile, asexually reproducing form of the parasite. Unlike the bradyzoites, the free tachyzoites are usually efficiently cleared by the host's immune response, although some manage to infect cells and form bradyzoites, thus maintaining the infection.

Ubiquitin-conjugating enzyme E2 H (UBE2H) is a member of the ubiquitin-conjugating enzyme family. Protein modification with ubiquitin is a vital cellular apparatus for directing abnormal or short-lived proteins for degradation. Ubiquitination requires at least 3 classes of enzymes: ubiquitin-activating enzymes (E1s) ubiquitin-conjugating enzymes (E2s) and ubiquitin-protein ligases (E3s). UBE2H receives ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins. UBE2H protein sequence is 100% identical to the mouse homolog and 98% identical to the frog and zebrafish homologs.

Small VCP/p97-interacting protein (SVIP) is involved in various cellular processes, including membrane fusion and ubiquitin-dependent protein degradation. SVIP functions as an inhibitor of the endoplasmic reticulum (ER)-associated degradation (ERAD) pathway. On the other hand, SVIP overexpression increased the levels of p62 protein and enhanced starvation-activated autophagy as well as stimulated sequestration of polyubiquitinated proteins and p62 in autophagosomes.

Ubiquitin Conjugating Enzyme E2Z, also known as UBE2z, is a protein coding gene which is a part of the ubiquitin-conjugating enzyme family. UBE2z catalyzes the covalent attachment of ubiquitin to various proteins. UBE2z takes part in in apoptosis regulation and is also a specific substrate for UBA6, not charged with ubiquitin by UBE1.

WHSC2 (NELF-A) is a protein factor required for DRB-sensitive transcription. WHSC2 is one of the 5 components of the multisubunit NELF complex which cooperates with DSIF to repress RNA polymerase II elongation. The Wolf-Hirschhorn syndrome is a multiple malformation syndrome characterized by mental and developmental defects resulting from a hemizygous deletion of the distal short arm of chromosome 4 (4p16.3).

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.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

Von Willebrand Factor A Domain Containing 2 (VWA2) is an extracellular matrix protein containing vWA-like domains. VWA2 contains a signal peptide sequence, an N-terminal VWA domain connected to 2 additional tandem vWA domains by a cysteine-rich sequence and an EGF-like domain. Also, another EGF-like domain is located at the C-terminus. Expression of VWA2 is induced in stage II, III and IV colon cancers and colon adenomas and is considered a novel serum marker for the diagnosis of early-stage colon cancer.

HIV-1 and HIV-2 appear to package their RNA differently. HIV-1 binds to any appropriate RNA whereas HIV-2 preferentially binds to mRNA which creates the Gag protein itself. This means that HIV-1 is better able to mutate. HIV-2 is transmitted in the same ways as HIV-1: Through exposure to bodily fluids such as blood, semen, tears and vaginal fluids.
Immunodeficiency develops more slowly with HIV-2.
HIV-2 is less infectious in the early stages of the virus than with HIV-1.
The infectiousness of HIV-2 increases as the virus progresses.
Major differences include reduced pathogenicity of HIV-2 relative to HIV-1, enhanced immune control of HIV-2 infection and often some degree of CD4-independence. Despite considerable sequence and phenotypic differences between HIV-1 and 2 envelopes, structurally they are quite similar. Both membrane-anchored proteins eventually form the 6-helix bundles from the N-terminal and C-terminal regions of the ectodomain, which is common to many viral and cellular fusion proteins and which seems to drive fusion.
HIV-1 gp41 helical regions can form more stable 6-helix bundles than HIV-2 gp41 helical regions however HIV-2 fusion occurs at a lower threshold temperature (25°C), does not require Ca2+ in the medium, is insensitive to treatment of target cells with cytochalasin B, and is not affected by target membrane glycosphingolipid composition.

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.

Superoxide dismutase Mn (soda) belongs to the iron/manganese superoxide dismutase family. SodA destroys radicals that are typically produced within the cells and which are toxic to biological systems. SodA works by catalyzing the dismutation of the superoxide radical O2- to O2 and H2O2, which are then metabolized to H2O and O2 by catalase and glutathione peroxidase.

UBE2D2 belongs to the E2 ubiquitin-conjugating enzyme family. UBE2D2 takes part in the ubiquitination of the tumor-suppressor protein p53, which is induced by an E3 ubiquitin-protein ligase. UBE2D2 catalyzes ubiquitination of IkB-alpha in a SCFB-TRCP and phosphorylation dependent method.

Coproporphyrinogen Oxidase (CPOX) which is localized to the internal membrane space of erythrocytes takes part in the 6th phase of heme biosynthesis. CPOX catalyzes the oxidative decarboxylation of propionic acid side chains of rings A and B of coproporphyrinogen III. Mutations in human CPOX gene forecast the clinical result of the disease, with either hepatic hereditary coproporphyria or hematological manifestations of erythropoietic harderoporphyria.