38 research outputs found
Substrate-assisted mechanism of RNP disruption by the spliceosomal Brr2 RNA helicase
No full textThe Brr2 RNA helicase disrupts the U4/U6 di-small nuclear RNA-protein complex (di-snRNP) during spliceosome activation via ATP-driven translocation on the U4 snRNA strand. However, it is unclear how bound proteins influence U4/U6 unwinding, which regions of the U4/U6 duplex the helicase actively unwinds, and whether U4/U6 components are released as individual molecules or as sub-complexes. Here, we set up a recombinant Brr2-mediated U4/U6 di-snRNP disruption system, showing that sequential addition of the U4/U6 proteins small nuclear ribonucleoprotein-associated protein 1 (Snu13), pre-mRNA processing factor 31 (Prp31), and Prp3 to U4/U6 di-snRNA leads to a stepwise decrease of Brr2-mediated U4/U6 unwinding, but that unwinding is largely restored by a Brr2 cofactor, the C-terminal Jab1/MPN domain of the Prp8 protein. Brr2-mediated U4/U6 unwinding was strongly inhibited by mutations in U4/U6 di-snRNAs that diminish the ability of U6 snRNA to adopt an alternative conformation but leave the number and kind of U4/U6 base pairs unchanged. Irrespective of the presence of the cofactor, the helicase segregated a Prp3-Prp31-Snu13-U4/U6 RNP into an intact Prp31-Snu13-U4 snRNA particle, free Prp3, and free U6 snRNA. Together, these observations suggest that Brr2 translocates only a limited distance on the U4 snRNA strand and does not actively release RNA-bound proteins. Unwinding is then completed by the partially displaced U6 snRNA adopting an alternative conformation, which leads to dismantling of the Prp3-binding site on U4/U6 di-snRNA but leaves the Prp31- and Snu13-binding sites on U4 snRNA unaffected. In this fashion, Brr2 can activate the spliceosome by stripping U6 snRNA of all precatalytic binding partners, while minimizing logistic requirements for U4/U6 di-snRNP reassembly after splicing
Appendix1_IMed_FU_Questionnaire_revised – Supplemental material for Self-reported Improvement in Side Effects and Quality of Life With Integrative Medicine in Breast Cancer Patients
No full textSupplemental material, Appendix1_IMed_FU_Questionnaire_revised for Self-reported Improvement in Side Effects and Quality of Life With Integrative Medicine in Breast Cancer Patients by Carolin C. Hack, Janina Hackl, Nina B. M. Hüttner, Hanna Langemann, Judith Schwitulla, Svenja Dietzel-Drentwett, Peter A. Fasching, Matthias W. Beckmann and Anna-Katharin Theuser in Integrative Cancer Therapies</p
The Role of Physical Embodiment of Humanoid Robot Interaction:Focusing on Backchannel Head Nods in Danish First Meeting Encounters
No full textAn important role for the communication management inhuman communication is head nods, e.g. as nonverbal feedback signal.Based on a Japanese study with virtual agents, have showed that theusing head nods in virtual agents elicited more verbal output from theuser, we look into the use of head nods in communications between userand a humanoid robot, Keepon robot and a virtual agent resembling acat that the user encounters for the first time
miR-27 negatively regulates pluripotency-associated genes in human embryonal carcinoma cells.
No full textHuman embryonic stem cells and human embryonal carcinoma cells have been studied extensively with respect to the transcription factors (OCT4, SOX2 and NANOG), epigenetic modulators and associated signalling pathways that either promote self-renewal or induce differentiation in these cells. The ACTIVIN/NODAL axis (SMAD2/3) of the TGFß signalling pathway coupled with FGF signalling maintains self-renewal in these cells, whilst the BMP (SMAD1,5,8) axis promotes differentiation. Here we show that miR-27, a somatic-enriched miRNA, is activated upon RNAi-mediated suppression of OCT4 function in human embryonic stem cells. We further demonstrate that miR-27 negatively regulates the expression of the pluripotency-associated ACTIVIN/NODAL axis (SMAD2/3) of the TGFß signalling pathway by targeting ACVR2A, TGFßR1 and SMAD2. Additionally, we have identified a number of pluripotency-associated genes such as NANOG, LIN28, POLR3G and NR5A2 as novel miR-27 targets. Transcriptome analysis revealed that miR-27 over-expression in human embryonal carcinoma cells leads indeed to a significant up-regulation of genes involved in developmental pathways such as TGFß- and WNT-signalling
User experience concept exploration - user needs as a source for innovation
No full textS.727-736We present a novel method for user-driven innovation: theUser Experience Concept Exploration. The method relies on a User Experience (UX) framework which assumes that a positive UX can be created by fulfilling basic human needs. Users are actively involved in the ideation and design process to support the generation of innovative product features that address individual needs and actual contexts of use. After introducing the UX Concept Exploration and its theoretical underpinnings, the paper describes an empirical study evaluating the effectiveness oft he method. The results show that the method is able to assess the most promising user-generated product features and combine them into a new concept which can enhance the positive user experience of a product
Security and Privacy for Modern and Emerging Mobile Systems
No full textThe fundamentals of secure systems can be presentedas the three cornerstones: authentication (trustworthinessof senders), integrity (inability to alter messages) and confidentiality(inability to read messages for anyone except theintended recipient). In this project, an android application hasbeen programmed by the author with the purpose of sendinggeographical data over a bluetooth connection in a secure peerto-peer manner. In the application, the three goals were metprimarily through the use of certificate validation, encryption anddigital signatures. The final application features a user-interfacewith a Google Maps interface, and query parameters that theuser can set when requesting data about a certain position.The final application would very much be considered secure inan environment where only two android devices are communicating.However, more steps would have to be taken if the applicationis to be deployed commercially. The primary questions arescalability, speed and further security complications
Primers that have been used for quantitative Real-time PCR.
No full text<p>Primers that have been used for quantitative Real-time PCR.</p
miR-27 inhibits OCT4 and LIN28 expression at both the transcriptional and translational level in embryonal carcinoma cells (NCCIT).
No full text<p>(A) Analysis of miR-27 expression was carried out for miR-27a and miR-27b using TaqMan-based PCR on total RNA samples isolated from NCCIT cells undergoing RA stimulated neuronal differentiation for seven days or by blocking TGFßR2 with SB431542 for seven days and normalized to the DMSO-treated control. (B) qRT-PCR of selected genes (log2-fold change relative to the negative control) was validated for NCCIT cells transfected once with miR-27 or treated with SB431542 for 48 h. NCCIT cells transfected with a scrambled miRNA mimic was used for normalization. (C) Relative <i>OCT4</i> and <i>LIN28</i> expression in NCCIT cells transfected with scrambled negative control miRNA mimics, let-7a, miR-125b, miR-27a, miR-200c or treated with SB431542 for 72 h and validated by qRT-PCR. (D) Western Blot analysis of OCT4 and LIN28 expression in NCCIT cells treated as described in (C). (E) Normalized densitometric-derived ratios of Western Blot presented in (D).</p
miR-27 directly inhibits a number of genes reported to sustain self-renewal in embryonic stem cells.
No full text<p>(A) Table showing three putative miR-27 target genes predicted by Diana Micro-T (DT), MiRanda (miRa), MirWalk (miRW) and TargetScan that maintain self-renewal. (B) Normalized GFP expression (48 hours post transfection) of HEK293 cells co-transfected with EGFP-sensors bearing parts of the 3′-UTR of <i>LIN28B</i>, <i>NR5A2</i>, <i>POLR3G</i>, <i>NANOG, SOX2 or OCT4</i> together with either miR-27 mimics or a scrambled negative control mimic (neg. con.). All transfections were performed twice in biological triplicates (n = 6) and GFP expression measured by flow cytometry. An unpaired two tailed t-test was performed to reveal significant differences (** p<0.01). (C) Upper row: Schematic timeline of hESC (H1) undergoing hepatic differentiation. Total RNA was isolated at day zero (undifferentiated H1), three days after endoderm priming (DE) and 14 days after hepatocyte differentiation (HE). Lower row: miR-27 expression was carried out for miR-27a and miR-27b using TaqMan-based PCR on total RNA samples from the above described stages, DE and HE and normalized to the untreated/undifferentiated H1 control.</p
