Rockefeller University

About: Rockefeller University is a education organization based out in New York, New York, United States. It is known for research contribution in the topics: Population & Gene. The organization has 15867 authors who have published 32938 publications receiving 2940261 citations. The organization is also known as: Rockefeller University & Rockefeller Institute.

Exploiting CRISPR-Cas nucleases to produce sequence-specific antimicrobials

Abstract: Antibiotics target conserved bacterial cellular pathways or growth functions and therefore cannot selectively kill specific members of a complex microbial population. Here, we develop programmable, sequence-specific antimicrobials using the RNA-guided nuclease Cas9 (refs.1,2) delivered by a bacteriophage. We show that Cas9, reprogrammed to target virulence genes, kills virulent, but not avirulent, Staphylococcus aureus. Reprogramming the nuclease to target antibiotic resistance genes destroys staphylococcal plasmids that harbor antibiotic resistance genes and immunizes avirulent staphylococci to prevent the spread of plasmid-borne resistance genes. We also show that CRISPR-Cas9 antimicrobials function in vivo to kill S. aureus in a mouse skin colonization model. This technology creates opportunities to manipulate complex bacterial populations in a sequence-specific manner.

Thermodynamic Basis of the Enhanced Specificity of Structured DNA Probes

Abstract: Molecular beacons are DNA probes that form a stem-and-loop structure and possess an internally quenched fluorophore. When they bind to complementary nucleic acids, they undergo a conformational transition that switches on their fluorescence. These probes recognize their targets with higher specificity than probes that cannot form a hairpin stem, and they easily discriminate targets that differ from one another by only a single nucleotide. Our results show that molecular beacons can exist in three different states: bound to a target, free in the form of a hairpin structure, and free in the form of a random coil. Thermodynamic analysis of the transitions between these states reveals that enhanced specificity is a general feature of conformationally constrained probes.

Daxx is an H3.3-specific histone chaperone and cooperates with ATRX in replication-independent chromatin assembly at telomeres

Abstract: The histone variant H33 is implicated in the formation and maintenance of specialized chromatin structure in metazoan cells H33-containing nucleosomes are assembled in a replication-independent manner by means of dedicated chaperone proteins We previously identified the death domain associated protein (Daxx) and the α-thalassemia X-linked mental retardation protein (ATRX) as H33-associated proteins Here, we report that the highly conserved N terminus of Daxx interacts directly with variant-specific residues in the H33 core Recombinant Daxx assembles H33/H4 tetramers on DNA templates, and the ATRX–Daxx complex catalyzes the deposition and remodeling of H33-containing nucleosomes We find that the ATRX–Daxx complex is bound to telomeric chromatin, and that both components of this complex are required for H33 deposition at telomeres in murine embryonic stem cells (ESCs) These data demonstrate that Daxx functions as an H33-specific chaperone and facilitates the deposition of H33 at heterochromatin loci in the context of the ATRX–Daxx complex