Project description:Males of the concave-eared frog (Odorrana tormota) have evolved an ultrasonic communication capacity to avoid masking by the widespread background noise of local fast-flowing streams, whereas females exhibit no ultrasonic sensitivity. However, the molecular mechanisms underlying the high-frequency hearing differences between the sexes of O. tormota are still poorly understood. In this study, we sequenced the brain transcriptomes of male and female O. tormota, and compared their differential gene expression. A total of 4,605 differentially expressed genes (DEGs) between the sexes of O. tormota were identified and eleven of them were related to auditory based on the annotation and enrichment analysis. Most of these DEGs in males showed a higher expression trend than females in both quantity and expression quantity. The highly expressed genes in males were relatively concentrated in neurogenesis, signal transduction and ion transport, whereas the up-expressed genes in females were mainly related to energy metabolism, the growth and development regulation of specific auditory cells. This is the first research to reveal the molecular mechanisms of sex differences in ultrasonic hearing between the sexes of O. tormota and will provide new insights into the genetic basis of the auditory adaptation in amphibians during their transition from water to land.
Project description:Shine-Dalgarno (SD) motifs are thought to play an important role in translational initiation in bacteria. Paradoxically, ribosome profiling studies in E. coli show no correlation between the strength of the SD in an mRNA and how efficiently it is translated. Performing profiling on ribosomes with altered anti-Shine-Dalgarno sequences, we reveal a genome-wide correlation between SD strength and ribosome occupancy that was previously masked by other contributing factors. Using the antibiotic retapamulin to trap initiation complexes at start codons, we find that the mutant ribosomes select start sites correctly, arguing that start sites are hard-wired for initiation through the action of other mRNA features. We show that A-rich sequences upstream of start codons promote initiation. Taken together, our genome-wide study reveals that SD motifs are not necessary for the ribosome to select where initiation occurs, though they do affect how efficiently initiation occurs at sites whose other features support initiation.
Project description:Homeostatic scaling allows neurons to maintain stable activity patterns by globally altering their synaptic strength in response to changing activity levels. Suppression of activity by blocking action potentials increases synaptic strength through an upregulation of surface AMPA receptors. Although this synaptic up-scaling was shown to require transcription, the molecular nature of the intrinsic transcription program underlying this process and its functional significance have been unclear. Using RNA-seq, we identified 73 genes that were specifically upregulated in response to activity suppression. In particular, Neuronal pentraxin-1 (Nptx1) increased within 6 h of activity blockade, and knockdown of this gene blocked the increase in synaptic strength. Notably, Nptx1 induction is mediated by calcium influx through the T-type Voltage-Gated Calcium Channel, as well as two transcription factors, SRF and ELK1. Taken together, these results uncover a transcriptional program that specifically operates when neuronal activity is suppressed, to globally coordinate the increase in synaptic strength.
2017-02-07 | GSE90988 | GEO
Project description:Feeding low-level benzethonium chloride can promote the start-up, fast recovery and long-term stable maintenance of partial nitrification for low-ammonium wastewater
| PRJNA813294 | ENA
Project description:Rapid start-up of partial nitrification process using benzethonium chloride-a novel nitrite oxidation inhibitor