28296194
Retrovirus Genome Replication: Priming Specificities of Plus-Strand DNA Synthesis
SUMMARY The retroviral reverse transcriptase is a multifunctional protein. Not only does it contain both RNA- and DNA-directed DNA synthesis activities but also it contains an endonuclease activity necessary for the integration of viral RNA and a RNase H. This latter activity can reduce to oligoribonucleotides viral RNA that has been reverse transcribed into minus-strand DNA. However, during avian retrovirus genome replication it does this in a highly specific manner so as to generate a specific 12-base primer for plus-strand DNA synthesis. Even though many other oligoribonucleotides are also made there is an efficient selection of the specific primer followed by its efficient utilization in plus-strand DNA synthesis, and subsequent removal. We have used a reconstructed system to gain an understanding of the factors that contribute towards these observed specificities.
5444612
Reassociation of 4 S and 5 S RNA's with the genome of avian sarcoma virus.
Abstract A tryptophan tRNA derived from the host cell serves as primer for the initiation of DNA synthesis by the reverse transcript ase of avian sarcoma virus (ASV). We have characterized the binding of primer to the viral genome by studying the reassociation of low molecular weight RNA's with high molecular weight subunits of ASV-RNA. Primer can be annealed to a limited number (two to four) of sites on the viral genome to reconstitute a template fully active with reverse transcriptase. The annealing is specific and accurate; none of the other 4 S RNA's found in ASV will reassociate with viral genome under any of the conditions tested, and the reconstructed complex denatures with the same T m as the native complex between primer and viral genome. These results further substantiate our previous conclusion that the primer in ASV is a single species of tRNA, although the normal host cell may contain other 4 S RNA's which could also serve as primer if they were included in the viral genome during assembly. Chicken ribosomal 5 S RNA also reanneals to the ASV genome, presumably by binding to the sites originally occupied by 5 S RNA in viral 70 S RNA.
27724235
Avian RNA tumor virus DNA before and after integration into the host genome.
33909578
The polypeptides of influenza virus. 1. Cytoplasmic synthesis and nuclear accumulation.
33501684
Tumor virus ribonucleic acid directed deoxyribonucleic acid synthesis: nucleotide sequence at the 5' terminus of nascent deoxyribonucleic acid.
24939123
In vitro transcription of mouse mammary tumor virus RNA into DNA.
The in vitro transcription of the B-type mouse mammary tumor virus RNA into DNA is similar to that obtained with certain C-type viruses: synthesis can be initiated on an RNA primer molecule approximately the size of a tRNA, and a unique linkage (rA-dC) exists between this primer and the DNA product.
22683096
Evidence for a putative biomarker for substance dependence.
Electrodermal response modulation (ERM) reflects the reduction in skin conductance response to an aversive stimulus that is temporally predictable relative to when it is unpredictable. Poor ERM is associated with substance dependence (SD). It was hypothesized that ERM is a putative biomarker for SD rather than for externalizing disorders generally. Participants included 83 controls (no SD, antisocial personality disorder [PD] or borderline PD), 52 participants with SD only (SD and no PD), 12 with PD only (antisocial and/or borderline PD and no SD), and 35 comorbid (having SD and PD). Diagnoses at definite and probable certainty levels were used and were determined by semistructured clinical interviews. ERM was calculated from skin conductance responses to predictable and unpredictable 2-s 110-dB white noise blasts. As expected, the SD-only and comorbid groups had significantly lower ERM scores than the control group, which did not differ significantly from the PD-only group. Results provide preliminary evidence that ERM is a putative biomarker for SD. Future research should examine cognitive correlates of ERM in an effort to understand why it relates to SD.
13468480
ESPERR: learning strong and weak signals in genomic sequence alignments to identify functional elements.
Genomic sequence signals - such as base composition, presence of particular motifs, or evolutionary constraint - have been used effectively to identify functional elements. However, approaches based only on specific signals known to correlate with function can be quite limiting. When training data are available, application of computational learning algorithms to multispecies alignments has the potential to capture broader and more informative sequence and evolutionary patterns that better characterize a class of elements. However, effective exploitation of patterns in multispecies alignments is impeded by the vast number of possible alignment columns and by a limited understanding of which particular strings of columns may characterize a given class. We have developed a computational method, called ESPERR (evolutionary and sequence pattern extraction through reduced representations), which uses training examples to learn encodings of multispecies alignments into reduced forms tailored for the prediction of chosen classes of functional elements. ESPERR produces a greatly improved Regulatory Potential score, which can discriminate regulatory regions from neutral sites with excellent accuracy ( approximately 94%). This score captures strong signals (GC content and conservation), as well as subtler signals (with small contributions from many different alignment patterns) that characterize the regulatory elements in our training set. ESPERR is also effective for predicting other classes of functional elements, as we show for DNaseI hypersensitive sites and highly conserved regions with developmental enhancer activity. Our software, training data, and genome-wide predictions are available from our Web site (http://www.bx.psu.edu/projects/esperr).
39760502
Commentary on Kong S and Bernstein K (2009) Childhood trauma as a predictor of eating psychopathology and its mediating variables in patients with eating disorders Journal of Clinical Nursing 18, 1897-1907.
24886138
Comparison and characteristics of motor vehicle accident (MVA) and non-MVA driving fears.
Prior research has revealed the diagnostic complexity among people who report driving fears. However, the focus on survivors of motor vehicle accidents (MVAs) and diagnostic samples may have inadvertently led to a relative neglect of the broader driving-fearful population. No studies could be located that compared MVA survivors with those who had not experienced an MVA. The aim of the present study was to address these deficits by comparing the characteristics of MVA and non-MVA driving-fearfuls and also exploring a range of characteristics associated with driving fears. One hundred and ninety media-recruited driving-fearfuls completed a questionnaire that assessed severity of anxiety and avoidance associated with a variety of driving situations. It was found that fear levels were similar to samples of driving phobics and MVA victims. There were no significant differences between MVA and non-MVA respondents on various measures of fear severity. In addition, the sample rated a high level of anxiety when driving with someone who criticizes their driving. Implications of the findings are discussed, along with suggestions for assessment and treatment of those with driving-related fears.
42563847
Driving fear and driving skills: comparison between fearful and control samples using standardised on-road assessment.
The present study explores driving skills in a group of 50 media-recruited driving-fearful and 50 control drivers, all of whom were women. Participants completed an on-road practical driving assessment with a professional driving instructor. Diagnostic as well as pre-post self-report and instructor driving assessments were conducted. Fearful drivers made more errors on the driving assessment than controls. However, the pattern of errors was identical for both groups, indicating that fear and anxiety may be associated with the number rather than the type of driving errors made. These differences remained when factors such as driving history, current driving frequency, and diagnosis were controlled using case selection. More research is needed to replicate the findings in more diverse samples. Additional work should also aim to clarify the specific role of driving skills in driving fear, which will facilitate treatment planning for exposure-based treatments and help identify cases where driving skills assessment may be appropriate.