New York University

About: New York University is a education organization based out in New York, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 72380 authors who have published 165545 publications receiving 8334030 citations. The organization is also known as: NYU & University of the City of New York.

A dicer-independent miRNA biogenesis pathway that requires Ago catalysis

Abstract: The nucleolytic activity of animal Argonaute proteins is deeply conserved, despite its having no obvious role in microRNA-directed gene regulation. In mice, Ago2 (also known as Eif2c2) is uniquely required for viability, and only this family member retains catalytic competence. To investigate the evolutionary pressure to conserve Argonaute enzymatic activity, we engineered a mouse with catalytically inactive Ago2 alleles. Homozygous mutants died shortly after birth with an obvious anaemia. Examination of microRNAs and their potential targets revealed a loss of miR-451, a small RNA important for erythropoiesis. Though this microRNA is processed by Drosha (also known as Rnasen), its maturation does not require Dicer. Instead, the pre-miRNA becomes loaded into Ago and is cleaved by the Ago catalytic centre to generate an intermediate 3' end, which is then further trimmed. Our findings link the conservation of Argonaute catalysis to a conserved mechanism of microRNA biogenesis that is important for vertebrate development.

Measurement reliability and agreement in psychiatry

Abstract: Psychiatric research has benefited from attention to measurement theories of reliability, and reliability/agreement statistics for psychopathology ratings and diagnoses are regularly reported in empirical reports. Nevertheless, there are still controversies regarding how reliability should be measured, and the amount of resources that should be spent on studying measurement quality in research programs. These issues are discussed in the context of recent theoretical and technical contributions to the statistical analysis of reliability. Special attention is paid to statistical studies published since Kraemer's 1992 review of reliability methods in this journal.

Efficient Private Matching and Set Intersection

Abstract: We consider the problem of computing the intersection of private datasets of two parties, where the datasets contain lists of elements taken from a large domain. This problem has many applications for online collaboration. We present protocols, based on the use of homomorphic encryption and balanced hashing, for both semi-honest and malicious environments. For lists of length k, we obtain O(k) communication overhead and O(k ln ln k) computation. The protocol for the semi-honest environment is secure in the standard model, while the protocol for the malicious environment is secure in the random oracle model. We also consider the problem of approximating the size of the intersection, show a linear lower-bound for the communication overhead of solving this problem, and provide a suitable secure protocol. Lastly, we investigate other variants of the matching problem, including extending the protocol to the multi-party setting as well as considering the problem of approximate matching.

G-protein-coupled receptor heterodimerization modulates receptor function

Abstract: The opioid system modulates several physiological processes, including analgesia, the stress response, the immune response and neuroendocrine function1. Pharmacological and molecular cloning studies have identified three opioid-receptor types, δ, κ and µ, that mediate these diverse effects2,3. Little is known about the ability of the receptors to interact to form new functional structures, the simplest of which would be a dimer. Structural and biochemical studies show that other G-protein-coupled receptors (GPCRs) interact to form homodimers4,5. Moreover, two non-functional receptors heterodimerize to form a functional receptor, suggesting that dimerization is crucial for receptor function6,7,8,9,10,11. However, heterodimerization between two fully functional receptors has not been documented. Here we provide biochemical and pharmacological evidence for the heterodimerization of two fully functional opioid receptors, κ and δ. This results in a new receptor that exhibits ligand binding and functional properties that are distinct from those of either receptor. Furthermore, the κ–δ heterodimer synergistically binds highly selective agonists and potentiates signal transduction. Thus, heterodimerization of these GPCRs represents a novel mechanism that modulates their function.

Role of the polycomb protein EED in the propagation of repressive histone marks

Abstract: Polycomb group proteins have an essential role in the epigenetic maintenance of repressive chromatin states. The gene-silencing activity of the Polycomb repressive complex 2 (PRC2) depends on its ability to trimethylate lysine 27 of histone H3 (H3K27) by the catalytic SET domain of the EZH2 subunit, and at least two other subunits of the complex: SUZ12 and EED. Here we show that the carboxy-terminal domain of EED specifically binds to histone tails carrying trimethyl-lysine residues associated with repressive chromatin marks, and that this leads to the allosteric activation of the methyltransferase activity of PRC2. Mutations in EED that prevent it from recognizing repressive trimethyl-lysine marks abolish the activation of PRC2 in vitro and, in Drosophila, reduce global methylation and disrupt development. These findings suggest a model for the propagation of the H3K27me3 mark that accounts for the maintenance of repressive chromatin domains and for the transmission of a histone modification from mother to daughter cells.