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Michele Cleary

Publications and source records attributed to Michele Cleary.

4 recordsLinked to original sources
PubMed2006

Widespread siRNA "off-target" transcript silencing mediated by seed region sequence complementarity.

Transfected siRNAs and miRNAs regulate numerous transcripts that have only limited complementarity to the active strand of the RNA duplex. This process reflects natural target regulation by miRNAs, but is an unintended ("off-target") consequence of siRNA-mediated silencing. Here we demonstrate that this unintended off-target silencing is widespread, and occurs in a manner reminiscent of target silencing by miRNAs. A high proportion of unintended transcripts silenced by siRNAs showed 3' UTR sequence complementarity to the seed region of the siRNA. Base mismatches within the siRNA seed region reduced the set of original off-target transcripts but generated new sets of silenced transcripts with sequence complementarity to the mismatched seed sequence. An inducible shRNA silenced a subset of transcripts that were silenced by an siRNA of the same sequence, demonstrating that unintended silencing is sequence mediated and is independent of delivery method. In all cases, off-target transcript silencing was accompanied by loss of the corresponding protein and occurred with dependence on siRNA concentration similar to that of silencing of the target transcript. Thus, short stretches of sequence complementarity to the siRNA or shRNA seed region are key to the silencing of unintended transcripts.

3' Untranslated Regions↗
PubMed2004

A resource for large-scale RNA-interference-based screens in mammals.

Gene silencing by RNA interference (RNAi) in mammalian cells using small interfering RNAs (siRNAs) and short hairpin RNAs (shRNAs) has become a valuable genetic tool. Here, we report the construction and application of a shRNA expression library targeting 9,610 human and 5,563 mouse genes. This library is presently composed of about 28,000 sequence-verified shRNA expression cassettes contained within multi-functional vectors, which permit shRNA cassettes to be packaged in retroviruses, tracked in mixed cell populations by means of DNA 'bar codes', and shuttled to customized vectors by bacterial mating. In order to validate the library, we used a genetic screen designed to report defects in human proteasome function. Our results suggest that our large-scale RNAi library can be used in specific, genetic applications in mammals, and will become a valuable resource for gene analysis and discovery.

Animals↗
PubMed2004

Prevalence of comorbid conditions and prescription medication use among patients with gout and hyperuricemia in a managed care setting.

BACKGROUND: : Comorbid disorders and multiple prescription drug use are common among patients with gout and/or hyperuricemia and may influence the clinical course and outcome of gout. OBJECTIVE: : We wanted to document the conditions and associated medications in a large group of patients with gout in a managed care setting. METHODS: : This study was a 2-year, retrospective, administrative claims analysis examining comorbid conditions and medication use among managed care enrollees with gout/hyperuricemia across the United States. RESULTS: : Of the 9482 study subjects (82.1% men, mean age 52 years), 57.9% had hypertension, 45.3% had a lipid disorder, 32.5% had both conditions, and 19.9% had diabetes mellitus. During the 24-month follow-up period, subjects had 5 +/- 3.14 (mean +/- standard deviation) different comorbid conditions and filled prescriptions for of 11.0 +/- 7.90 different medications. The most commonly filled prescriptions included antihypertensive drugs, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins), and nonsteroidal antiinflammatory drugs (NSAIDs). CONCLUSIONS: : The study indicates a high prevalence of both comorbid conditions and multiple medication use among managed care enrollees with gout and/or hyperuricemia. Heightened awareness of these associated disorders is important because they may warrant treatment of their own accord and often some modification of gout management. Drugs, particularly diuretics and prophylactic aspirin, could potentially contribute to the development of hyperuricemia and gout.

Journal Article↗