Human cytomegalovirus DNA polymerase comprises a catalytic subunit, UL54, and an accessory subunit, UL44, the interaction of which may serve as a target for the development of new antiviral drugs. Using a high-throughput screen, we identified a small molecule, (5-((dimethylamino)methylene-3-(methylthio)-6,7-dihydrobenzo[c]thiophen-4(5H)-one), that selectively inhibits the interaction of UL44 with a UL54-derived peptide in a time-dependent manner, full-length UL54, and UL44-dependent long-chain DNA synthesis. A crystal structure of the compound bound to UL44 revealed a covalent reaction with lysine residue 60 and additional noncovalent interactions that cause steric conflicts that would prevent the UL44 connector loop from interacting with UL54.
View Article and Find Full Text PDFGenome editing by designer nucleases is a rapidly evolving technology utilized in a highly diverse set of research fields. Among all fields, the T7 endonuclease mismatch cleavage assay, or Surveyor assay, is the most commonly used tool to assess genomic editing by designer nucleases. This assay, while relatively easy to perform, provides only a semi-quantitative measure of mutation efficiency that lacks sensitivity and accuracy.
View Article and Find Full Text PDFRare-cleaving nucleases have emerged as valuable tools for creating targeted genomic modification for both therapeutic and research applications. MegaTALs are novel monomeric nucleases composed of a site-specific meganuclease cleavage head with additional affinity and specificity provided by a TAL effector DNA binding domain. This fusion product facilitates the transformation of meganucleases into hyperspecific and highly active genome engineering tools that are amenable to multiplexing and compatible with multiple cellular delivery methods.
View Article and Find Full Text PDFLAGLIDADG homing endonucleases (LHEs) are compact endonucleases with 20-22 bp recognition sites, and thus are ideal scaffolds for engineering site-specific DNA cleavage enzymes for genome editing applications. Here, we describe a general approach to LHE engineering that combines rational design with directed evolution, using a yeast surface display high-throughput cleavage selection. This approach was employed to alter the binding and cleavage specificity of the I-Anil LHE to recognize a mutation in the mouse Bruton tyrosine kinase (Btk) gene causative for mouse X-linked immunodeficiency (XID)-a model of human X-linked agammaglobulinemia (XLA).
View Article and Find Full Text PDFRare-cleaving endonucleases have emerged as important tools for making targeted genome modifications. While multiple platforms are now available to generate reagents for research applications, each existing platform has significant limitations in one or more of three key properties necessary for therapeutic application: efficiency of cleavage at the desired target site, specificity of cleavage (i.e.
View Article and Find Full Text PDFHoming endonucleases (HEs) can be used to induce targeted genome modification to reduce the fitness of pathogen vectors such as the malaria-transmitting Anopheles gambiae and to correct deleterious mutations in genetic diseases. We describe the creation of an extensive set of HE variants with novel DNA cleavage specificities using an integrated experimental and computational approach. Using computational modeling and an improved selection strategy, which optimizes specificity in addition to activity, we engineered an endonuclease to cleave in a gene associated with Anopheles sterility and another to cleave near a mutation that causes pyruvate kinase deficiency.
View Article and Find Full Text PDFSeveral herpes simplex virus 1 microRNAs are encoded within or near the latency associated transcript (LAT) locus, and are expressed abundantly during latency. Some of these microRNAs can repress the expression of important viral proteins and are hypothesized to play important roles in establishing and/or maintaining latent infections. We found that in lytically infected cells and in acutely infected mouse ganglia, expression of LAT-encoded microRNAs was weak and unaffected by a deletion that includes the LAT promoter.
View Article and Find Full Text PDFHoming endonucleases have great potential as tools for targeted gene therapy and gene correction, but identifying variants of these enzymes capable of cleaving specific DNA targets of interest is necessary before the widespread use of such technologies is possible. We identified homologues of the LAGLIDADG homing endonuclease I-AniI and their putative target insertion sites by BLAST searches followed by examination of the sequences of the flanking genomic regions. Amino acid substitutions in these homologues that were located close to the target site DNA, and thus potentially conferring differences in target specificity, were grafted onto the I-AniI scaffold.
View Article and Find Full Text PDFProtein kinase C (PKC) is a multigene family of serine/threonine protein kinases involved in cell signaling pathways of proliferation and motility. PKC interacts with Rho GTPases in the regulation of the actin cytoskeleton. The PKC-alpha isozyme binds the Rho GTPase cdc42, and both are coordinated with the Rac-phosphatidylinositol-3 kinase (PI3K) signaling pathway in melanoma cell invasion and migration on extracellular matrix proteins.
View Article and Find Full Text PDFThe keratinocyte microparasol, composed of a perinuclear microtubular/melano-phagolysosomal complex, protects the nucleus from UV-induced DNA damage. We have previously demonstrated that cytoplasmic dynein is the motor involved in the perinuclear-directed aggregation of phagocytosed melanosomes. Dynactin, of which p150(Glued) is the major subunit, can link directly to microtubules and links organelles to dynein at different domains.
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