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A Correction to this paper has been published: https://doi.org/10.1038/s41597-021-00858-2.

Streptomyces species are gram-positive bacteria with GC-rich linear genomes and they serve as dominant reservoirs for producing clinically and industrially important secondary metabolites. Genome mining of Streptomyces revealed that each Streptomyces species typically encodes 20–50 secondary metabolite biosynthetic gene clusters (smBGCs), emphasizing their potential for novel compound discovery. Unfortunately, most of smBGCs are uncharacterized in terms of their products and regulation since they are silent under laboratory culture conditions. To translate the genomic potential of Streptomyces to practical applications, it is essential to understand the complex regulation of smBGC expression and to identify the underlying regulatory elements. To progress towards these goals, we applied two Next-Generation Sequencing methods, dRNA-Seq and Term-Seq, to industrially relevant Streptomyces species to reveal the 5´ and 3´ boundaries of RNA transcripts on a genome scale. This data provides a fundamental resource to aid our understanding of Streptomyces’ regulation of smBGC expression and to enhance their potential for secondary metabolite synthesis., Measurement(s) 5´-ends of transcripts • 3´-ends of transcripts • RNA • TSS • transcription_termination_signal Technology Type(s) dRNA-Seq • Term-Seq • RNA sequencing Factor Type(s) Streptomyces growth phase Sample Characteristic - Organism Streptomyces avermitilis • Streptomyces clavuligerus • Streptomyces coelicolor • Streptomyces griseus • Streptomyces lividans • Streptomyces tsukubensis • Streptomyces venezuelae Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.13259393

Increasing demand for recombinant therapeutic proteins has warranted the need for an efficient host cell to produce high-quality proteins, with a high yield. Chinese hamster ovary (CHO) cells appear to meet this demand, and their genetic tailoring will facilitate improvements in their productivity for recombinant proteins. Recent advances in programmable RNA-guided Cas9 nuclease (RGN) have facilitated CHO cell engineering via site-specific genome editing. One critical determinant for increasing genomeediting efficiency is attaining a balanced expression level of Cas9 nuclease and guide RNAs in the nucleus. Here, we achieved high-level expression of Cas9 nuclease and single guide RNA (sgRNA), enhancing expression levels approximately three-fold over the conventional methodology by using an iterative transfection approach. We demonstrated that high abundance of sgRNA and Cas9 nuclease induced a two-fold increase in the site-specific mutation rate on average for both single and multiple genetic targets. Sequencing results confirmed frame-shift mutations at targeted genomic loci created by error-prone NHEJassociated mutations. Moreover, we controlled the amount of sgRNA-Cas9 complex formation in vitro and delivered the complex directly to cells, resulting in the maximization of mutation frequency by the high-level of sgRNA-Cas9 complex. Importantly, mutation rates of putative off-target sites remained minimal in spite of the improved genome-editing efficiency. These results provide an efficient strategy for editing the CHO genome with the reduction of the time-consuming screening efforts aimed at isolating clones with desirable properties.

This paper proposes a digital tool which enables users to create the iron filing effects. It is a 2D interactive system, where the user provides a silhouette of a 2D target shape and interactively specifies various parameters of magnets. Then, the patterns of the iron filings are automatically generated through the principle of magnetism. The system also provides a real-time feedback while the user updates the magnet parameters, i.e., the magnet lines are interactively displayed such that the user can speculate the final patterns of iron filings. The experimental results show that a variety of artwork can be created by the proposed tool.