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At least 55 records · Page 3

Recombinant production of a functional SARS-CoV-2 spike receptor binding domain in the green algae Chlamydomonas reinhardtii

Recombinant production of viral proteins can be used to produce vaccine antigens or reagents to identify antibodies in patient serum. Minimally, these proteins must be correctly folded and have appropriate post-translation modifications. Here we report the production of the SARS-CoV-2 spike protein Receptor Binding Domain (RBD) in the green algae Chlamydomonas . RBD fused to a fluorescent reporter protein accumulates as an intact protein when targeted for ER-Golgi retention or secreted from the cell, while a chloroplast localized version is truncated. The ER-retained RBD fusion protein was able to bind the human ACE2 receptor, the host target of SARS-CoV-2, and was specifically out-competed by mammalian cell-produced recombinant RBD, suggesting that the algae produced proteins are sufficiently post-translationally modified to act as authentic SARS-CoV-2 antigens. Because algae can be grown at large scale very inexpensively, this recombinant protein may be a low cost alternative to other expression platforms.

59 BASIC BIOLOGICAL SCIENCES↗

Rerouting reductant flux via protein tethering enhances biohydrogen production in Thermococcus kodakarensis

Microbes that generate copious amounts of hydrogen (H 2 ) via dark fermentation are a promising means to evolve and improve renewable biofuels. Many anaerobic hyperthermophilic archaea, such as the fast-growing, genetically tractable, heterotroph Thermococcus kodakarensis, produce generous quantities of H2 and provide an idealized platform to further optimize naturally high levels of biohydrogen reduction. Precise genetic manipulations and modifications to growth conditions have already resulted in substantial increases to H2 output but additional improvements are desired. An unexamined and potentially valuable route towards increased H 2 production is to tether select electron donor and acceptor proteins together to reroute and maximize the flow of electrons towards H 2 production. Such strategies have shown promise in Bacteria and Eukarya but have not yet been investigated in thermophilic Archaea. Here, we generate and evaluate twelve novel T. kodakarensis strains wherein a proteinaceous electron carrier (a ferredoxin, Fd) is physically tethered to the membrane-bound-hydrogenase (MBH), the sole H 2 producing enzyme, to direct electron flux towards biohydrogen generation. Growth assessments and H 2 output measurements demonstrate that strains encoding protein-fusions evolve up to ~ 40% more H2 per cell than the host strain. Eliminating H 2 consumption and alternative routes of electron sinks in concert with protein tethering further increased H2 output per cell for a maximum increase of ~ 66% over the host strain. Our results demonstrate that rerouting electron flux via protein tethering coupled with the elimination of reductant sinks is a promising means towards improved biohydrogen production in T. kodakarensis. KEY POINTS: Protein tethering between redox proteins can reroute electron flux in vivo. Enforced protein proximity results in ~ 40% increases in H2 production per cell. Protein-tethering provides a generalizable framework to redirect redox metabolism.

59 BASIC BIOLOGICAL SCIENCES↗

Targeted protein degradation systems to enhance Wnt signaling

Molecules that facilitate targeted protein degradation (TPD) offer great promise as novel therapeutics. The human hepatic lectin asialoglycoprotein receptor (ASGR) is selectively expressed on hepatocytes. We have previously engineered an anti-ASGR1 antibody-mutant RSPO2 (RSPO2RA) fusion protein (called SWEETS) to drive tissue-specific degradation of ZNRF3/RNF43 E3 ubiquitin ligases, which achieved hepatocyte-specific enhanced Wnt signaling, proliferation, and restored liver function in mouse models, and an antibody–RSPO2RA fusion molecule is currently in human clinical trials. In the current study, we identified two new ASGR1- and ASGR1/2-specific antibodies, 8M24 and 8G8. High-resolution crystal structures of ASGR1:8M24 and ASGR2:8G8 complexes revealed that these antibodies bind to distinct epitopes on opposing sides of ASGR, away from the substrate-binding site. Both antibodies enhanced Wnt activity when assembled as SWEETS molecules with RSPO2RA through specific effects sequestering E3 ligases. In addition, 8M24-RSPO2RA and 8G8-RSPO2RA efficiently downregulate ASGR1 through TPD mechanisms. These results demonstrate the possibility of combining different therapeutic effects and degradation mechanisms in a single molecule.

59 BASIC BIOLOGICAL SCIENCES↗

Controlling Protein Enrichment in Lipid Sponge Phase Droplets using SNAP–Tag Bioconjugation

All cells use organized lipid compartments to facilitate specific biological functions. Membrane-bound organelles create defined spatial environments that favor unique chemical reactions while isolating incompatible biological processes. Despite the fundamental role of cellular organelles, there is a scarcity of methods for preparing functional artificial lipid-based compartments. In this work, we demonstrate a robust bioconjugation system for sequestering proteins into zwitterionic lipid sponge phase droplets. Incorporation of benzylguanine (BG)-modified phospholipids that form stable covalent linkages with an O 6 -methylguanine DNA methyltransferase (SNAP-tag) fusion protein enables programmable control of protein capture. We show that this methodology can be used to anchor hydrophilic proteins at the lipid-aqueous interface, concentrating them within an accessible but protected chemical environment. SNAP-tag technology enables the integration of proteins that regulate complex biological functions in lipid sponge phase droplets, and should facilitate the development of advanced lipid-based artificial organelles.

59 BASIC BIOLOGICAL SCIENCES↗

Microscale thermophoresis as a powerful tool for screening glycosyltransferases involved in cell wall biosynthesis

Background: Identification and characterization of key enzymes associated with cell wall biosynthesis and modification is fundamental to gain insights into cell wall dynamics. However, it is a challenge that activity assays of glycosyltransferases are very low throughput and acceptor substrates are generally not available. Results: We optimized and validated microscale thermophoresis (MST) to achieve high throughput screening for glycosyltransferase substrates. MST is a powerful method for the quantitative analysis of protein-ligand interactions with low sample consumption. The technique is based on the motion of molecules along local temperature gradients, measured by fluorescence changes. We expressed glycosyltransferases as YFP-fusion proteins in tobacco and optimized the MST method to allow the determination of substrate binding affinity without purification of the target protein from the cell lysate. The application of this MST method to the β-1,4-galactosyltransferase AtGALS1 validated the capability to screen both nucleotide-sugar donor substrates and acceptor substrates. We also expanded the application to members of glycosyltransferase family GT61 in sorghum for substrate screening and function prediction. Conclusions: This method is rapid and sensitive to allow determination of both donor and acceptor substrates of glycosyltransferases. MST enables high throughput screening of glycosyltransferases for likely substrates, which will narrow down their in vivo function and help to select candidates for further studies. Additionally, this method gives insight into biochemical mechanism of glycosyltransferase function.

59 BASIC BIOLOGICAL SCIENCES↗

Hyperfusogenic Mutations Destabilize the Postfusion Six-Helix Bundle of the Measles Virus Fusion Glycoprotein

Fusion of the host membrane and viral envelope by class I viral fusion proteins is driven by the assembly of a postfusion six-helix bundle formed through antiparallel interactions between N-terminal (HR1) and C-terminal (HR2) heptad-repeat regions. Although mutations in these regions of the measles virus (MeV) fusion (F) glycoprotein are known to promote neuropathogenic and hyperfusogenic phenotypes, their effects on postfusion core stability have not been systematically examined. Here, we combine peptide biophysics and X-ray crystallography to interrogate how mutations within the HR2 domain, present in native neuropathogenic MeV isolates (e.g., L454W and N462K) and laboratory-generated hyperfusogenic variants (e.g., L454M and T461A), influence postfusion 6HB assembly. Circular dichroism (CD) spectroscopy reveals that, with few exceptions, these mutations decrease postfusion core stability, despite their association with enhanced fusion activity. We also report the first crystal structure of the wild-type MeV postfusion core as well as structures of six hyperfusogenic variants, enabling high-resolution comparison of the molecular basis of destabilization. Structural analysis shows that these effects arise from localized perturbations to steric packing, hydrogen bonding networks, and helix-stabilizing interactions within HR2, while the overall 6HB architecture remains conserved. Together, these results indicate that hyperfusogenic mutations are not associated with stabilization of the postfusion state and are instead consistent with models in which hyperfusogenicity arises from a reduction in the energetic barrier to fusion, potentially through effects on prefusion stability or triggering efficiency. These findings establish key sequence-structure–stability relationships governing coiled-coil assembly and provide a framework for the design of HR1- and HR2-based fusion inhibitors.

Genetics↗

Atypical chemoreceptor arrays accommodate high membrane curvature

The prokaryotic chemotaxis system is arguably the best-understood signaling pathway in biology. In all previously described species, chemoreceptors organize into a hexagonal (P6 symmetry) extended array. Here, we report an alternative symmetry (P2) of the chemotaxis apparatus that emerges from a strict linear organization of the histidine kinase CheA in Treponema denticola cells, which possesses arrays with the highest native curvature investigated thus far. Using cryo-ET, we reveal that Td chemoreceptor arrays assume an unusual arrangement of the supra-molecular protein assembly that has likely evolved to accommodate the high membrane curvature. The arrays have several atypical features, such as an extended dimerization domain of CheA and a variant CheW-CheR-like fusion protein that is critical for maintaining an ordered chemosensory apparatus. Furthermore, the previously characterized Td oxygen sensor ODP influences CheA ordering. These results suggest a greater diversity of the chemotaxis signaling system than previously thought.

59 BASIC BIOLOGICAL SCIENCES↗

Use of Split‐Intein Proteins to Design a Small Molecule Biosensor in Plants

Understanding how plants perceive their environment is fundamental to advancing agricultural productivity and sustainability. Many biological small molecules, including those involved in microbial recognition, act rapidly at the plant cell surface, but the absence of tools to visualise these dynamics has limited our ability to dissect plant–microbe communication. To address this gap, we sought to create a genetically encoded biosensor that couples ligand-induced protein dimerization with the production of a fluorescent reporter. Inteins are peptide regions that excise themselves from precursor proteins and ligate the flanking chains (exteins). When each half of a split intein is fused to one of two dimerizing proteins, ligand binding brings them into proximity, inducing intein splicing and ligation of flanking extein sequences (Kang et al. 2022). Similar to previous studies, we split the yeast vacuolar ATPase subunit 1 (VMA1) intein, creating a protein biosensor that produces eGFP upon protein dimerization after ligand binding (Figure 1A) (Mootz et al. 2003). Specifically, eGFP halves (i.e., non-functional N- and C-terminal GFP fragments) were fused to the intein halves, resulting in two fusion proteins: N-terminal GFP::N-terminal intein and C-terminal intein::C-terminal GFP (Figure 1A).

Boone, Brandon A. [Oak Ridge National Laboratory (↗

A Comprehensive Scientific Survey of Excipients Used in Currently Marketed, Therapeutic Biological Drug Products

The steady development of biotechnology-derived therapeutic biologics over the last few decades has generated drugs that are now standard medical treatments for a range of indications. While the development of protein products has surged in recent years, the formulation and delivery of these complex molecules have relied on drug-specific studies and, in some instances, data from non-proteinaceous drug products. The commonalities, trends, and gaps in excipient technologies used to support the development of therapeutic proteins largely remain unexplored due to the drug-specific nature of many formulations. Using a comprehensive and relational database approach, we aimed to provide a scientific survey of all approved or licensed biotechnology-derived drug products with the goal of providing evidence-based information on common attributes and trending features in protein product excipients. We examined 665 formulations, and 395 unique formulations based on having unique excipients within them, that supported 211 therapeutic proteins as of June 2020. We report the prevalence of each excipient class and excipient chemical used in eight different drug types including monoclonal antibodies, antibody conjugates, cytokines and growth factors, enzymes, polypeptide hormones, pulmonary surfactants, recombinant fusion proteins, and toxins. We also report the prevalence by excipient type among all therapeutic proteins, in the context of each drug’s recommended pH range, concentration ranges for excipients, and route of administration. The results of our analyses indicate certain excipients common to monoclonal antibodies, cytokines, and polypeptide hormones. We also report on excipients unique to protein drug products, such as amino acids, solubilizers, and lyoprotectants. Overall, our report summarizes the current landscape of excipients used in marketed biotechnology-derived therapeutic biologic products.

60 APPLIED LIFE SCIENCES↗

Enhanced X-ray diffraction of in vivo-grown μNS crystals by viscous jets at XFELs

μNS is a 70 kDa major nonstructural protein of avian reoviruses, which cause significant economic losses in the poultry industry. They replicate inside viral factories in host cells, and the μNS protein has been suggested to be the minimal viral factor required for factory formation. Thus, determining the structure of μNS is of great importance for understanding its role in viral infection. In the study presented here, a fragment consisting of residues 448–605 of μNS was expressed as an EGFP fusion protein in Sf9 insect cells. EGFP-μNS (448–605) crystallization in Sf9 cells was monitored and verified by several imaging techniques. Cells infected with the EGFP-μNS (448–605) baculovirus formed rod-shaped microcrystals (5–15 µm in length) which were reconstituted in high-viscosity media (LCP and agarose) and investigated by serial femtosecond X-ray diffraction using viscous jets at an X-ray free-electron laser (XFEL). The crystals diffracted to 4.5 Å resolution. A total of 4227 diffraction snapshots were successfully indexed into a hexagonal lattice with unit-cell parameters a = 109.29, b = 110.29, c = 324.97 Å. The final data set was merged and refined to 7.0 Å resolution. Preliminary electron-density maps were obtained. While more diffraction data are required to solve the structure of μNS (448–605) , the current experimental strategy, which couples high-viscosity crystal delivery at an XFEL with in cellulo crystallization, paves the way towards structure determination of the μNS protein.

59 BASIC BIOLOGICAL SCIENCES↗

The CRISPR effector Cam1 mediates membrane depolarization for phage defence

Prokaryotic type III CRISPR–Cas systems provide immunity against viruses and plasmids using CRISPR-associated Rossman fold (CARF) protein effectors. Recognition of transcripts of these invaders with sequences that are complementary to CRISPR RNA guides leads to the production of cyclic oligoadenylate second messengers, which bind CARF domains and trigger the activity of an effector domain. Whereas most effectors degrade host and invader nucleic acids, some are predicted to contain transmembrane helices without an enzymatic function. Whether and how these CARF–transmembrane helix fusion proteins facilitate the type III CRISPR–Cas immune response remains unknown. Here we investigate the role of cyclic oligoadenylate-activated membrane protein 1 (Cam1) during type III CRISPR immunity. Structural and biochemical analyses reveal that the CARF domains of a Cam1 dimer bind cyclic tetra-adenylate second messengers. In vivo, Cam1 localizes to the membrane, is predicted to form a tetrameric transmembrane pore, and provides defence against viral infection through the induction of membrane depolarization and growth arrest. These results reveal that CRISPR immunity does not always operate through the degradation of nucleic acids, but is instead mediated via a wider range of cellular responses.

59 BASIC BIOLOGICAL SCIENCES↗

Targeting KDM4 for treating PAX3-FOXO1–driven alveolar rhabdomyosarcoma

Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic Paired Box 3–Forkhead Box O1 (PAX3-FOXO1) fusion protein, which governs a core regulatory circuitry transcription factor network. Here, we show that the histone lysine demethylase 4B (KDM4B) is a therapeutic vulnerability for PAX3-FOXO1 + RMS. Genetic and pharmacologic inhibition of KDM4B substantially delayed tumor growth. Suppression of KDM4 proteins inhibited the expression of core oncogenic transcription factors and caused epigenetic alterations of PAX3-FOXO1–governed superenhancers. Combining KDM4 inhibition with cytotoxic chemotherapy led to tumor regression in preclinical PAX3-FOXO1 + RMS subcutaneous xenograft models. In summary, we identified a targetable mechanism required for maintenance of the PAX3-FOXO1–related transcription factor network, which may translate to a therapeutic approach for fusion-positive RMS.

Cell Biology↗

Mutagenesis of Human Cytomegalovirus Glycoprotein L Disproportionately Disrupts gH/gL/gO over gH/gL/pUL128-131

Herein, cell-free and cell-to-cell spread of herpesviruses involves a core fusion apparatus comprised of the fusion protein glycoprotein B (gB) and the regulatory factor gH/gL. The human cytomegalovirus (HCMV) gH/gL/gO and gH/gL/pUL128-131 facilitate spread in different cell types. The gO and pUL128-131 components bind distinct receptors, but how the gH/gL portions of the complexes functionally compare is not understood. We previously characterized a panel of gL mutants by transient expression and showed that many were impaired for gH/gL-gB-dependent cell-cell fusion but were still able to form gH/gL/pUL128-131 and induce receptor interference. Here, the gL mutants were engineered into the HCMV BAC clones TB40/e-BAC4 (TB), TR, and Merlin (ME), which differ in their utilization of the two complexes for entry and spread. Several of the gL mutations disproportionately impacted gH/gL/gO-dependent entry and spread over gH/gL/pUL128-131 processes. The effects of some mutants could be explained by impaired gH/gL/gO assembly, but other mutants impacted gH/gL/gO function. Soluble gH/gL/gO containing the L201 mutant failed to block HCMV infection despite unimpaired binding to PDGFRα, indicating the existence of other important gH/gL/gO receptors. Another mutant (L139) enhanced the gH/gL/gO-dependent cell-free spread of TR, suggesting a “hyperactive” gH/gL/gO. Recently published crystallography and cryo-electron microscopy studies suggest structural conservation of the gH/gL underlying gH/gL/gO and gH/gL/pUL128-131. However, our data suggest important differences in the gH/gL of the two complexes and support a model in which gH/gL/gO can provide an activation signal for gB.

59 BASIC BIOLOGICAL SCIENCES↗

Leveraging Hydration Forces for Size-Specific Nanoparticle Enrichment with a Redox-Responsive Silica-Binding Elastin-Like Polypeptide

Elastin-like polypeptides (ELPs) are low-complexity proteins that coacervate above a characteristic lower critical solution temperature (LCST). While the thermoresponsiveness of ELPs has been widely exploited in the biomedical and biomaterials fields, their ability to mediate nanoparticle assembly below their transition temperature remains largely unexplored. Here, we show that unmodified ELPs induce the reversible flocculation of silica nanoparticles (SiNPs) by forming backbone hydrogen bonds with surface silanols. Interparticle bridging is modulated by ELP length and concentration and by the presence of N- and C-terminal anchoring groups such as a cysteine residue and a Car9 silica-binding peptide. Using a redox-responsive fusion protein consisting of disulfide-bonded ELP domains terminated by Car9 segments, we stabilize 20 nm SiNPs under oxidizing conditions while triggering particle flocculation upon addition of reductant. We find that SiNP sedimentation under reducing conditions exhibits a sharp dependency on particle size that arises from the curvature-dependent structure of surface silanols. While the isolated silanols of SiNPs smaller than 30 nm are efficiently engaged by the ELP domains of Car9-anchored proteins, repulsion forces associated with the presence of a layer of molecular water together with increased electrostatic repulsion preclude efficient engagement of H-bonded silanols displayed on the surface of SiNPs larger than 60 nm. We harness these findings to selectively enrich SiNPs based on size and expand the concept to titania (TiO2) by demonstrating that rutile nanoparticles can be stabilized or sedimented with solid-binding ELPs by adjusting the solution pH to promote or discourage the formation of a hydration layer. These strategies should prove broadly useful for the separation of other oxides and their polymorphs and provide a tunable strategy for nanoparticle assembly and bioinspired colloidal design.

ELP↗

Computational design of closely related proteins that adopt two well-defined but structurally divergent folds

The plasticity of naturally occurring protein structures, which can change shape considerably in response to changes in environmental conditions, is critical to biological function. While computational methods have been used for de novo design of proteins that fold to a single state with a deep free-energy minimum [P.-S. Huang, S. E. Boyken, D. Baker, Nature 537, 320–327 (2016)], and to reengineer natural proteins to alter their dynamics [J. A. Davey, A. M. Damry, N. K. Goto, R. A. Chica, Nat. Chem. Biol.13, 1280–1285 (2017)] or fold [P. A. Alexander, Y. He, Y. Chen, J. Orban, P. N. Bryan, Proc. Natl. Acad. Sci. U.S.A. 106, 21149–21154 (2009)], the de novo design of closely related sequences which adopt well-defined but structurally divergent structures remains an outstanding challenge. We designed closely related sequences (over 94% identity) that can adopt two very different homotrimeric helical bundle conformations—one short (~66 Å height) and the other long (~100 Å height)—reminiscent of the conformational transition of viral fusion proteins. Crystallographic and NMR spectroscopic characterization shows that both the short- and long-state sequences fold as designed. We sought to design bistable sequences for which both states are accessible, and obtained a single designed protein sequence that populates either the short state or the long state depending on the measurement conditions. The design of sequences which are poised to adopt two very different conformations sets the stage for creating large-scale conformational switches between structurally divergent forms.

59 BASIC BIOLOGICAL SCIENCES↗

The Magnetosome Protein, Mms6 from Magnetospirillum magneticum Strain AMB-1, Is a Lipid-Activated Ferric Reductase

Magnetosomes of magnetotactic bacteria consist of magnetic nanocrystals with defined morphologies enclosed in vesicles originated from cytoplasmic membrane invaginations. Although many proteins are involved in creating magnetosomes, a single magnetosome protein, Mms6 from Magnetospirillum magneticum strain AMB-1, can direct the crystallization of magnetite nanoparticles in vitro. The in vivo role of Mms6 in magnetosome formation is debated, and the observation that Mms6 binds Fe3+ more tightly than Fe2+ raises the question of how, in a magnetosome environment dominated by Fe3+, Mms6 promotes the crystallization of magnetite, which contains both Fe3+ and Fe2+. Here we show that Mms6 is a ferric reductase that reduces Fe3+ to Fe2+ using NADH and FAD as electron donor and cofactor, respectively. Reductase activity is elevated when Mms6 is integrated into either liposomes or bicelles. Analysis of Mms6 mutants suggests that the C-terminal domain binds iron and the N-terminal domain contains the catalytic site. Although Mms6 forms multimers that involve C-terminal and N-terminal domain interactions, a fusion protein with ubiquitin remains a monomer and displays reductase activity, which suggests that the catalytic site is fully in the monomer. However, the quaternary structure of Mms6 appears to alter the iron binding characteristics of the C-terminal domain. These results are consistent with a hypothesis that Mms6, a membrane protein, promotes the formation of magnetite in vivo by a mechanism that involves reducing iron.

59 BASIC BIOLOGICAL SCIENCES↗

Arabinogalactan Structures of Repetitive Serine-Hydroxyproline Glycomodule Expressed by Arabidopsis Cell Suspension Cultures

Arabinogalactan-proteins (AGPs) are members of the hydroxyproline-rich glycoprotein (HRGP) superfamily. They are heavily glycosylated with arabinogalactans, which are usually composed of a β-1,3-linked galactan backbone with 6-O-linked galactosyl, oligo-1,6-galactosyl, or 1,6-galactan side chains that are further decorated with arabinosyl, glucuronosyl, rhamnosyl, and/or fucosyl residues. Here, our work with Hyp-O-polysaccharides isolated from (Ser-Hyp)32-EGFP (enhanced green fluorescent protein) fusion glycoproteins overexpressed in transgenic Arabidopsis suspension culture is consistent with the common structural features of AGPs isolated from tobacco. In addition, this work confirms the presence of β-1,6-linkage on the galactan backbone identified previously in AGP fusion glycoproteins expressed in tobacco suspension culture. Furthermore, the AGPs expressed in Arabidopsis suspension culture lack terminal-rhamnosyl residues and have a much lower level of glucuronosylation compared with those expressed in tobacco suspension culture. These differences not only suggest the presence of distinct glycosyl transferases for AGP glycosylation in the two systems, but also indicate the existence of minimum AG structures for type II AG functional features.

59 BASIC BIOLOGICAL SCIENCES↗

Impact of structural biology and the protein data bank on us fda new drug approvals of low molecular weight antineoplastic agents 2019–2023

Abstract Open access to three-dimensional atomic-level biostructure information from the Protein Data Bank (PDB) facilitated discovery/development of 100% of the 34 new low molecular weight, protein-targeted, antineoplastic agents approved by the US FDA 2019–2023. Analyses of PDB holdings, the scientific literature, and related documents for each drug-target combination revealed that the impact of structural biologists and public-domain 3D biostructure data was broad and substantial, ranging from understanding target biology (100% of all drug targets), to identifying a given target as likely druggable (100% of all targets), to structure-guided drug discovery (>80% of all new small-molecule drugs, made up of 50% confirmed and >30% probable cases). In addition to aggregate impact assessments, illustrative case studies are presented for six first-in-class small-molecule anti-cancer drugs, including a selective inhibitor of nuclear export targeting Exportin 1 (selinexor, Xpovio), an ATP-competitive CSF-1R receptor tyrosine kinase inhibitor (pexidartinib,Turalia), a non-ATP-competitive inhibitor of the BCR-Abl fusion protein targeting the myristoyl binding pocket within the kinase catalytic domain of Abl (asciminib, Scemblix), a covalently-acting G12C KRAS inhibitor (sotorasib, Lumakras or Lumykras), an EZH2 methyltransferase inhibitor (tazemostat, Tazverik), and an agent targeting the basic-Helix-Loop-Helix transcription factor HIF-2α (belzutifan, Welireg).

60 APPLIED LIFE SCIENCES↗