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Zika virus (ZIKV) belongs to the family Flaviviridae and the genus Flavivirus, it is transmitted by daytime-active Aedes mosquitoes, such as A. aegypti and A. albopictus. The Zika virus is related to the dengue, yellow fever, Japanese encephalitis, and West Nile viruses. Much like the other flaviviruses, Zika virus is enveloped and icosahedral and has a nonsegmented, single-stranded, positive-sense RNA genome. Zika fever is an infection, which often causes no symptoms or only mild ones, like a mild form of dengue fever, and it is treated by rest. As of February 2016, there has been mounting evidence that Zika fever in pregnant women can cause abnormal brain development in their fetuses by mother-to-child transmission, which may result in miscarriage or microcephaly, however it is not yet known whether Zika virus causes microcephaly. Furthermore, a connection has been established with neurologic conditions in infected adults, including Guillain–Barre syndrome. Since the 1950s, Zika virus has been detected only within a narrow equatorial belt from Africa to Asia. Between the years 2013 and 2014, Zika virus has spread eastward across the Pacific Ocean to French Polynesia, New Caledonia, the Cook Islands, and Easter Island, and in 2015 to Mexico, Central America, the Caribbean, and South America, where the Zika outbreak has reached pandemic levels.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.
It has recently been shown that SARS (severe acute respiratory syndrome) is caused by a human coronavirus. Human coronaviruses are the major cause of upper respiratory tract illness, such as the common cold, in humans. Coronaviruses are positive-stranded RNA viruses, featuring the largest viral RNA genomes known to date (27-31 kb). The first step in coronavirus infection is binding of the viral spike protein, a 139-kDa protein, to certain receptors on host cells. The spike protein is the main surface antigen of the coronavirus. The glycosilated spike protein (as well as the nucleocapsid protein) can be detected in infected cell culture supernatants with antisera from SARS patients.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

A fusion tag called FLAG consists of eight amino acids (AspTyrLysAspAspAspAspLys) including an enterokinase-cleavage site. FLAG is specifically designed for immunoaffinity chromatography. It allows elution under non-denaturing conditions. Several antibodies against this peptide have been developed. One antibody denoted as M1 binds the peptide in the presence of bivalent metal cations preferably Ca(+). Elution is effected by chelating agents. Another strategy is competitive elution with excess of free Flag Peptide.
The FLAG peptide purifies and detects recombinant fusion proteins. FLAG peptide is useful in Western blotting, immunocytochemistry, immunoprecipitation, flow cytometry, protein purification, and in the study of protein-protein interactions, cell ultrastructure, and protein localization. Flag peptide is a hydrophilic tag which significantly improves the detection and purification of recombinant fusion proteins.

SNAP-25 is an necessary element of the core complex that is responsible for presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters and this protein exists as two alternative isoforms, SNAP25A and SNAP25B which differ by 9 amino acids in central portion of these proteins.

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.

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.

Trichomonas vaginalis, an anaerobic, flagellated protozoan parasite, is most dominant protozoan causing sexual transmitted disease. T. vaginalis induced vaginal tract infection occurs as multiple steps involving interactions between host macromolecules and protozoan virulent factor. Adhension protein P65 of T. vaginalis has a vital part in assisting the penetration into vaginal tract surface.

The Fas receptor (CD95) mediates apoptotic signaling by Fas-ligand expressed on the surface of other cells. The Fas-FasL interaction plays an important role in the immune system and lack of this system leads to autoimmunity, indicating that Fas-mediated apoptosis removes self-reactive lymphocytes. Fas signaling is also involved in immune surveillance to remove transformed cells and virus infected cells. Binding of FAS to oligimerized FasL on another cell activates apoptotic signaling through a cytoplasmic domain termed the death domain that interacts with signaling adaptors including FAF, FADD and DAX to activate the caspase proteolytic cascade. Caspase-8 and caspase-10 are first activated, to then cleave and activate downstream caspases, and a variety of cellular substrates that lead to cell death. Caspases cleave nuclear lamins, causing the nucleus to break down and lose its normal structure and another caspase substrate is DFF, inducing cleavage and degradation of the genome. Other caspase substrates are involved in cytoskeletal structure, cell cycle regulation and signaling pathways. Activation of JNK kinase, activation of Jun, and production of ceramide may also play roles in Fas-mediated apoptosis. Activation of fas-mediated apoptosis is opposed by I-FLICE and FAP. Viruses and tumors may escape immune surveillance in part through suppression of fas-mediated apoptosis using similar mechanisms.

C1q is the first component of the classical pathway of complement activation. C1q along with the enzymatically active components C1r and C1s forms the C1 complex. When C1 binds to immunoglobulins in the form of immune complexes, it leads to activation of C1r and C1s proteases and a further activates the classical pathway of complement. C1q is a glycoprotein that belongs to the collectin family, having a molecular weight of about 410-462 kDa. C1q is a hexamer composed of globular heads attached to collagen-like triple-helix tails. The globular heads of C1q exclusively bind to the CH2 domain of IgG molecules or the CH3 domain of IgM. Each heavy chain of the immunoglobulin molecule contains a single binding site for C1q. Given that C1q must bind to no less than two heavy chains in order to alter its conformation and activate C1r and C1s, its activation follows only after binding to immunoglobulins in the form of immune complexes bound to multivalent antigens. C1q’s main physiological role is in the clearance of immune complexes and apoptotic bodies from the organism. Interruption of this process may lead to development of autoimmunity. Individuals with genetic deficiencies of C1q or other components of the classical pathway are at risk to develop SLE. C1q specifically binds to apoptotic bodies of human keratinocytes, vascular endothelial cells and lymphocytes. Complement components C1q and bound C3 mediate the clearance of apoptotic bodies. Hence, C1q may advance the clearance of autoantigens, avoiding stimulation of the immune system. Nonetheless, an extended exposition of the immune system to the neoepitope exposed on C1q molecules bound to immune complexes or apoptotic bodies could ultimately lead to an autoimmune response against C1q itself and to an altered complement function. C1q deficiency may also lead to disruption of the negative selection of autoreactive B cells. C1q along with other specific recognition proteins bind to the highly conserved lupus antigens (dsDNA and nuclear proteins) and activate the complement system. Autoantibodies against C1q (anti-C1q) are found in a number of autoimmune and infectious diseases like glomerulonephritis (GN) and lupus erythematosus (SLE), these antibodies are significant in clinical practice due to their negative predictive value.

Japanese encephalitis previously known as Japanese B encephalitis is a virus from the family Flaviviridae. it is closely related to the West Nile virus and St. Louis encephalitis virus. Positive sense single stranded RNA genome is packaged in the capsid, formed by the capsid protein. The outer envelope is formed by envelope (E) protein and is the protective antigen. It aids in entry of the virus to the inside of the cell. The genome also encodes several nonstructural proteins also (NS1,NS2a,NS2b,NS3,N4a,NS4b,NS5). NS1 is produced as secretory form also. NS3 is a putative helicase, and NS5 is the viral polymerase. It has been noted that the Japanese encephalitis virus (JEV) infects the lumen of the endoplasmic reticulum (ER) and rapidly accumulates substantial amounts of viral proteins for the JEV. Japanese Encephalitis is diagnosed by detection of antibodies in serum and CSF (cerebrospinal fluid) by IgM capture ELISA.

BID accession number NP_001187 is a pro-apoptotic Bcl-2 protein having only the BH3 domain. In reaction to apoptotic signaling, BID interacts with another Bcl-2 family of cell death regulators, called Bax, they form a heterodimer resulting to the insertion of Bax into the outer mitochondrial membrane. Bax induces the opening of the mitochondrial voltage-dependent anion channel which leads to the release of cytochrome c and other pro-apoptotic factors from the mitochondria resulting in activation of caspases. BID is a mediator of mitochondrial damage induced by caspase-8 (CASP8). CASP8 cleaves BID, and the COOH-terminal part translocates to mitochondria where it triggers cytochrome c release. The major proteolytic product p15 BID releasea cytochrome c. Isoform 1, Isoform 2 and Isoform 4 induce ice-like proteases and apoptosis while Isoform 3 does not induce apoptosis.

S100A10 is a member of the S100 family of proteins contains two EF-hand calcium-binding motifs and is thought to be involved in the regulation of a number of cellular processes including cell cycle progression and differentiation. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21. S100A10 may function in exocytosis and endocytosis.

AURKA (Aurora Kinase A) belongs to the mitotic serine/threonine kinases family. AURKA is a cell cycle-regulated kinase which may be involved in microtubule formation and/or stabilization at the spindle pole during chromosome segregation. AURKA is found at the centrosome in interphase cells and at the spindle poles in mitosis. Since the AURKA expression is cell-cycle regulated, it is low in G1/S, it accumulates during G2/M, and it decreases rapidly after. AURKA is involved in important processes during mitosis and meiosis whose proper function is essential for healthy cell proliferation. In addition, AURKA plays an essential role in tumourigenesis and is overexpressed in various types of cancers. AURKA is strongly expressed in the testis, colon, ovarian, prostate, neuroblastoma, breast and cervical cancer cell lines and weakly in skeletal muscle, thymus and spleen. AURKA interacts with its substrates BORA and ARHGEF2, as well as with TACC1 and CPEB1.
Defects in the AURKA gene cause numerical centrosome aberrations including aneuploidy. AURKA overexpression has been linked to chromosomal instability in colorectal cancer. AURKA expression may have a prognostic significance in ovarian carcinoma.

T cell immunoreceptor with Ig and ITIM domains or TIGIT, is an immune receptor located on part of T cells and Natural Killer Cells(NK). TIGIT is also known as Vstm3 and WUCAM. The receptor can bind with high affinity to dendritic cells(DCs), CD155(PVR) on macrophages, etc., and it can bind with lower affinity to CD112(PVRL2). TIGIT can inhibit the cytotoxicity of Natural Killer Cells through its ITIM domain via antibodies against the interaction with PVR and the activity is directed. It has been show on research that TIGIT-Fc fusion molecule can have interaction with PVR on dendritic cells and elevate its IL-10 secretion level or lower the secretion on IL-12 under the stimulation of LPS, moreover, it can inhibit the activation of T cell in vivo.

PTX-2 or Pentraxin-2 is a phylogenetically conserved protein, commonly moving with homopentameric blood protein or with a protein that recognizes receptors of the innate immune system. The protein’s specific binding abilities may show that PTX-2 is specially bound in sites where injury accrued, therefore helps to eliminate damaged tissue by ways that are not phlogistics.

Zika virus (ZIKV) belongs to the family Flaviviridae and the genus Flavivirus, it is transmitted by daytime-active Aedes mosquitoes, such as A. aegypti and A. albopictus. The Zika virus is related to the dengue, yellow fever, Japanese encephalitis, and West Nile viruses. Much like the other flaviviruses, Zika virus is enveloped and icosahedral and has a nonsegmented, single-stranded, positive-sense RNA genome. Zika fever is an infection, which often causes no symptoms or only mild ones, like a mild form of dengue fever, and it is treated by rest. As of February 2016, there has been mounting evidence that Zika fever in pregnant women can cause abnormal brain development in their fetuses by mother-to-child transmission, which may result in miscarriage or microcephaly, however it is not yet known whether Zika virus causes microcephaly. Furthermore, a connection has been established with neurologic conditions in infected adults, including Guillain–Barre syndrome. Since the 1950s, Zika virus has been detected only within a narrow equatorial belt from Africa to Asia. Between the years 2013 and 2014, Zika virus has spread eastward across the Pacific Ocean to French Polynesia, New Caledonia, the Cook Islands, and Easter Island, and in 2015 to Mexico, Central America, the Caribbean, and South America, where the Zika outbreak has reached pandemic levels.

AnsA is a cytoplasmic asparaginase from E.coli involved in intracellular asparagine utilization. E.coli has 2 L-asparaginases: the cytoplasmic type I form (ansA) and the periplasmic type II form (ansB). AnsA (Type L asparaginase) is constitutively expressed and is obligatory for the growth of the bacteria on asparagine as the sole nitrogen source.

NANOG is a multidomain homeobox transcription factor which functions to maintain the undifferentiated state of pluripotent stem cells. NANOG expression counteracts the differentiation-promoting signals induced by the extrinsic factors LIF, Stat3 and BMP. Once NANOG expression is downregulated, cell differentiation can proceed. Proteins which regulate NANOG expression include transcription factors Oct4, SOX2, FoxD3, and Tcf3 and tumor suppressor p53.

BNIP1 belongs to the of the BCL2/adenovirus E1B 19 kd-interacting protein (BNIP) family. BNIP1 interacts with the E1B 19 kDa protein, which defends cells from virally-induced cell death. In addition, BNIP1 interacts with E1B 19 kDa-like sequences of BCL2 which is an additional apoptotic protector. Adding up, BNIP1 is implicated in vesicle transport into the endoplasmic reticulum. Alternative splicing results of BNIP1 in four protein products with identical N- and C-termini have been found.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

Zika virus (ZIKV) belongs to the family Flaviviridae and the genus Flavivirus, it is transmitted by daytime-active Aedes mosquitoes, such as A. aegypti and A. albopictus. The Zika virus is related to the dengue, yellow fever, Japanese encephalitis, and West Nile viruses. Much like the other flaviviruses, Zika virus is enveloped and icosahedral and has a nonsegmented, single-stranded, positive-sense RNA genome. Zika fever is an infection, which often causes no symptoms or only mild ones, like a mild form of dengue fever, and it is treated by rest. As of February 2016, there has been mounting evidence that Zika fever in pregnant women can cause abnormal brain development in their fetuses by mother-to-child transmission, which may result in miscarriage or microcephaly, however it is not yet known whether Zika virus causes microcephaly. Furthermore, a connection has been established with neurologic conditions in infected adults, including Guillain–Barre syndrome.

NANOG is a multidomain homeobox transcription factor which functions to maintain the undifferentiated state of pluripotent stem cells. NANOG expression counteracts the differentiation-promoting signals induced by the extrinsic factors LIF, Stat3 and BMP. Once NANOG expression is downregulated, cell differentiation can proceed. Proteins which regulate NANOG expression include transcription factors Oct4, SOX2, FoxD3, and Tcf3 and tumor suppressor p53.