The P3 domain of E. coli ribonuclease P RNA can be truncated and replaced

AbstractWe prepared some truncated and replaced P3 mutants of Escherichia coli RNase P RNA, and used them to examine the RNase P ribozyme and holoenzyme reactions of a pre-tRNA substrate. The results indicated that mutations in the P3 domain did not affect the cleavage site selection of the pre-tRNA substrate, but did affect the efficiency of cleavage of the substrate. Results of stepwise truncation of the P3 domain and its replacement by the TAR sequence showed that the P3 domain of the E. coli RNase P was able to be truncated to certain length and was replaceable, but could not be deleted in the ribozyme

A custom magnetoencephalography device reveals brain connectivity and high reading/decoding ability in children with autism

A subset of individuals with autism spectrum disorder (ASD) performs more proficiently on certain visual tasks than may be predicted by their general cognitive performances. However, in younger children with ASD (aged 5 to 7), preserved ability in these tasks and the neurophysiological correlates of their ability are not well documented. In the present study, we used a custom child-sized magnetoencephalography system and demonstrated that preserved ability in the visual reasoning task was associated with rightward lateralisation of the neurophysiological connectivity between the parietal and temporal regions in children with ASD. In addition, we demonstrated that higher reading/decoding ability was also associated with the same lateralisation in children with ASD. These neurophysiological correlates of visual tasks are considerably different from those that are observed in typically developing children. These findings indicate that children with ASD have inherently different neural pathways that contribute to their relatively preserved ability in visual tasks

Different target-site specificities of the hairpin ribozyme in cis and trans cleavages

AbstractThe hairpin ribozyme cleaves a phosphodiester bond at the 5' side of a 5'GUC3' sequence of an RNA with high efficiency. An RNA having a 5'GUA3' sequence instead of the GUC sequence is a poor substrate for this ribozyme. Here, we show that this is indeed so in a trans-acting ribozyme system, but in a cis-acting ribozyme system this ribozyme cleaves the 5' side of a GUA sequence as efficiently as the wild-type cleaves the GUC sequence. One base substitution in the ribozyme also affected the target-site specificity in the cis-acting system