RMRP Is a Non-Coding RNA Essential for Early Murine Development

RMRP is a non-coding RNA that is ubiquitously expressed in both humans and mice. RMRP mutations that lead to decreased RMRP levels are found in the pleiotropic syndrome Cartilage Hair Hypoplasia. To assess the effects of deleting RMRP, we engineered a targeting vector that contains loxP sequences flanking RMRP and created hemizygous mice harboring this engineered allele (RMRP conditional). We found that insertion of this cassette suppressed RMRP expression, and we failed to obtain viable mice homozygous for the RMRP conditional allele. Furthermore, we were unable to obtain viable homozygous RMRP null mice, indicating that RMRP is essential for early embryonic development

Elimination of Mcl-1 is required for the initiation of apoptosis following ultraviolet irradiation

Ultraviolet (UV) irradiation of HeLa cells triggers an apoptotic response mediated by mitochondria. Biochemical analysis of this response revealed that the elimination of cytosolic inhibitors is required for mitochondrial release of cytochrome c and subsequent caspase activation. These inhibitors were found to be Mcl-1 and Bcl-x(L), two antiapoptotic members of the Bcl-2 family. Following UV treatment, Mcl-1 protein synthesis is blocked, the existing pool of Mcl-1 protein is rapidly degraded by the proteasome, and cytosolic Bcl-x(L) translocates to the mitochondria. These events are sequential; the elimination of Mcl-1 is required for the translocation of Bcl-x(L). The disappearance of Mcl-1 is also required for other mitochondrial apoptotic events including Bax translocation, cytochrome c release, and caspase activation

Is it Worth to Repeat Endoscopic Retrograde Cholangiopancreaticography after Failed Precut? Short Report from a Tertiary Care Hospital in North India

Aim: The aim of this study is to determine the success rate of biliary cannulation in cases where endoscopic retrograde cholangiopancreatography (ERCP) is repeated after failed precut sphincterotomy. Materials and Methods: In this retrospective study, consecutive ERCPs performed between August 2013 and June 2017 were included. Data was analyzed for indication of ERCP, success rate at initial cannulation attempt, use of precut sphincterotomy, biliary access rate after precut, repeat ERCP rate, and associated complications. Results: A total of 1872 ERCPs were included in the study. Of these, 55% were done for common bile duct stones, 37% for malignant biliary obstruction, and 8% for biliary leak. During the initial ERCP, 84.9% cases had successful biliary cannulation. Nearly 86.8% cases undergoing precut sphincterotomy achieved biliary access. Repeat ERCP was done in 28 cases after a median interval of 3 days and biliary cannulation was achieved in 78.5% cases. Conclusion: Repeat ERCP after 3 days in cases of failed initial precut sphincterotomy should be practiced and recommended as this allows definitive biliary therapy in majority of such patients and prevents morbidity and mortality from other invasive alternative therapies

<i>RMRP</i> depletion is embryonic lethal.

<p><i>RMRP</i> depletion is embryonic lethal.</p

<i>RMRP</i> depletion leads to reduced levels of <i>RMRP</i> transcript.

<p>Total RNA was produced from E13.5 MEFs and <i>RMRP</i> level was measured by A. qRT-PCR B. Northern blot using either a sense or antisense <i>RMRP</i> probe. Error bars represent SD of three replicas.</p

Targeting of murine <i>RMRP</i>.

<p>A. Murine targeting vector (MTV) B. Southern blot of ES cells following selection for alleles with integrated MTV (the southern probe is shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026270#pone-0026270-g001" target="_blank">figure 1a</a>) C. PCR analysis of RC (<i>RMRP</i> conditional) pups D. PCR analysis of pups derived from the interbreeding of RC mice and mice expressing CMV-Cre.</p

Genes near <i>RMRP</i> are not essential for cellular viability.

<p>MEFs from E13.5 mice of either A. WT or B. <i>RMRP</i>+/− were transfected with siRNAs targeting <i>Ccdc107</i> or <i>E130</i>. Three days later RNA was extracted from the cells and qRT-PCR was preformed using primers for <i>RMRP</i>, <i>Ccdc107</i> or <i>E130</i>. C. The same cells as in A and B were plated (5000 cells/well) in a 96 well plate and 7 days post transfection cell number was assessed by Cell titer glow. Error bars represent SD of three replicas.</p