A signal peptide is a short peptide present at the N-terminus of most newly synthesized proteins that are destined toward the secretory pathway. These proteins include those that reside either inside certain organelles, secreted from the cell, or inserted into most cellular membranes. Although most type I membrane-bound proteins have signal peptides, most type II and multi-spanning membrane-bound proteins are targeted to the secretory pathway by their first transmembrane domain, which biochemically resembles a signal sequence except that it is not cleaved. They are a kind of target peptide.
Protein kinase B (PKB), also known as Akt, is the collective name of a set of three serine/threonine-specific protein kinases that play key roles in multiple cellular processes such as glucose metabolism, apoptosis, cell proliferation, transcription, and cell migration.
Myristoylation is a lipidation modification where a myristoyl group, derived from myristic acid, is covalently attached by an amide bond to the alpha-amino group of an N-terminal glycine residue. Myristic acid is a 14-carbon saturated fatty acid (14:0) with the systematic name of n-tetradecanoic acid. This modification can be added either co-translationally or post-translationally. N-myristoyltransferase (NMT) catalyzes the myristic acid addition reaction in the cytoplasm of cells. This lipidation event is the most common type of fatty acylation and is present in many organisms, including animals, plants, fungi, protozoans and viruses. Myristoylation allows for weak protein–protein and protein–lipid interactions and plays an essential role in membrane targeting, protein–protein interactions and functions widely in a variety of signal transduction pathways.
Bruton's tyrosine kinase, also known as tyrosine-protein kinase BTK, is a tyrosine kinase that is encoded by the BTK gene in humans. BTK plays a crucial role in B cell development.
Buparvaquone is a naphthoquinone antiprotozoal drug related to atovaquone. It is a promising compound for the therapy and prophylaxis of all forms of theileriosis. Buparvaquone has been shown to have anti-leishmanial activity in vitro. It can be used to treat bovine East Coast fever protozoa in vitro, along with the only other substance known – Peganum harmala. It is the only really effective commercial therapeutic product against bovine theileriosis, where it has been used since the late 1980s.
Group-specific antigen, or gag, is the polyprotein that contains the core structural proteins of an Ortervirus. It was named as such because scientists used to believe it was antigenic. Now it is known that it makes up the inner shell, not the envelope exposed outside. It makes up all the structural units of viral conformation and provides supportive framework for mature virion.
Mammarenavirus juninense, better known as the Junin virus or Junín virus (JUNV), is an arenavirus in the Mammarenavirus genus that causes Argentine hemorrhagic fever (AHF). The virus took its original name from the city of Junín, around which the first cases of infection were reported, in 1958.
Cluster of differentiation antigen 135 (CD135) also known as fms like tyrosine kinase 3, receptor-type tyrosine-protein kinase FLT3, or fetal liver kinase-2 (Flk2) is a protein that in humans is encoded by the FLT3 gene. FLT3 is a cytokine receptor which belongs to the receptor tyrosine kinase class III. CD135 is the receptor for the cytokine Flt3 ligand (FLT3L).
A fusion mechanism is any mechanism by which cell fusion or virus–cell fusion takes place, as well as the machinery that facilitates these processes. Cell fusion is the formation of a hybrid cell from two separate cells. There are three major actions taken in both virus–cell fusion and cell–cell fusion: the dehydration of polar head groups, the promotion of a hemifusion stalk, and the opening and expansion of pores between fusing cells. Virus–cell fusions occur during infections of several viruses that are health concerns relevant today. Some of these include HIV, Ebola, and influenza. For example, HIV infects by fusing with the membranes of immune system cells. In order for HIV to fuse with a cell, it must be able to bind to the receptors CD4, CCR5, and CXCR4. Cell fusion also occurs in a multitude of mammalian cells including gametes and myoblasts.
Glycylpeptide N-tetradecanoyltransferase 2 known also as N-myristoyltransferase, is an enzyme that in humans is encoded by the NMT2 gene.
In enzymology, a glycylpeptide N-tetradecanoyltransferase is an enzyme that catalyzes the chemical reaction
Glycylpeptide N-tetradecanoyltransferase 1 also known as myristoyl-CoA:protein N-myristoyltransferase 1 (NMT-1) is an enzyme that in humans is encoded by the NMT1 gene. It belongs to the protein N-terminal methyltransferase and glycylpeptide N-tetradecanoyltransferase family of enzymes. This enzyme can be inhibited by NMT inhibitors.
Lestaurtinib is a tyrosine kinase inhibitor structurally related to staurosporine. This semisynthetic derivative of the indolocarbazole K252a was investigated by Cephalon as a treatment for various types of cancer. It is an inhibitor of the kinases fms-like tyrosine kinase 3 (FLT3), Janus kinase 2 (JAK2), tropomyosin receptor kinase (trk) A (TrkA), TrkB and TrkC.
Panobinostat, sold under the brand name Farydak, is a medication used for the treatment of multiple myeloma. It is a hydroxamic acid and acts as a non-selective histone deacetylase inhibitor.
Crizotinib, sold under the brand name Xalkori among others, is an anti-cancer medication used for the treatment of non-small cell lung carcinoma (NSCLC). Crizotinib inhibits the c-Met/Hepatocyte growth factor receptor (HGFR) tyrosine kinase, which is involved in the oncogenesis of a number of other histological forms of malignant neoplasms. It also acts as an ALK and ROS1 inhibitor.
C16 is a drug which acts as a selective inhibitor of the enzyme double-stranded RNA-dependent protein kinase (PKR). It has been shown to effectively inhibit PKR function in vivo and has neuroprotective and nootropic effects in animal studies. C16 has anti-viral activity, in A549 cells, against hemorrhagic viruses of mammarenaviruses such as lassa and junin.
Isatuximab, sold under the brand name Sarclisa, is a monoclonal antibody (mAb) medication for the treatment of multiple myeloma.
IMP-1088 is an enzyme inhibitor of the human N-myristoyltransferases NMT1 and NMT2, an analog of Zelenirstat, capable of preventing viruses that require myristoylated proteins for their life cycle such as pox viruses, mammarenaviruses, and rhinoviruses, an area of research relating to potential treatment of the monkeypox, lassa fever, and common cold among others. IMP-1088 works to keep cells from generating infectious virus by targeting the cell instead of the rhinovirus itself. It does this by blocking the NMT protein of the host cell which prevents the virus from assembling its capsid, since viral capsid myristoylation by host NMT is essential for assembly. It is thought unlikely that viruses will evolve resistance to such an approach since IMP-1088 works against the human cell and not the virus. IMP-1088 can inhibit mammarenaviruses such as LCMV virus and the hemorragic fever viruses such as lassa and junin, where IMP-1088 targets the Z matrix protein and the signal peptide of glycoprotein 1 of these viruses, these myristoylated viral proteins are essential for the viral life cycle including assembly, budding and propagation. Both vaccinia and monkeypox viruses have four myristoylated proteins that can be targeted which would interrupt viral lifecycle, inhibition of myristoylation has been shown to completely inhibit viral propagation in combination therapies.
Brequinar (DuP-785) is a drug that acts as a potent and selective inhibitor of the enzyme dihydroorotate dehydrogenase. It blocks synthesis of pyrimidine based nucleotides in the body and so inhibits cell growth. Brequinar was invented by DuPont Pharmaceuticals in the 1980s. In 2001, Bristol-Myers Squibb acquired DuPont, and in 2017, Clear Creek Bio acquired the rights to brequinar from BMS.
These are small molecules that target and inhibit N-myristoyltransferases, which block the addition of myristic acid to the penultimate glycine of proteins with myristoylation signal. The prototype is the DDD85646, and the analogues IMP-1088 and PCLX-001. N-myristoyltransferase inhibitors have been shown to have potent antiviral and anti-neoplastic activities.
