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Objective To explore the effects of replacing different components of PAM-less adenine base editor (ABE) on its editing efficiency. Methods ABEmax was replaced with Tad-8e in SpRY-ABEmax to construct SpRY-ABE8e. Then the connecting peptide 3xGGS-XTEN-3xGGS between Cas9 protein variant SpRY and Tad-8e was shortened to PAPAPA. ABEs and sgRNA expression plasmids were co-transfected into HEK 293T cells. After 24 hours, cells were incubated with 1.5 μg/mL puromycin. After 72 hours, the cells expressing green fluorescent protein were flow sorted and the cell genome was extracted and the expected editing sites were amplified by PCR technology. Sanger sequencing was performed and Beat tool was used to estimate the editing efficiency of each site. Results Compared with control group, SpRY-ABEmax, SpRY-ABE8e has higher editing efficiency and expanded editing window(P＜0.05); editing window of SpRY-ABE8e can be limited to a certain extent while maintaining editing efficiency by using the shortened linker peptide. Conclusions The editing efficiency can be improved by replacing different components of PAM-less ABE, which will provide more candidate tools for gene therapy in the future.

There is no effective therapeutic drug and intervention method for pulmonary fibrosis(PF). There are many mechanisms of using mesenchymal stem cell in the treatment of idiopathic pulmonary fibrosis(IPF), radiation pulmonary fibrosis(RPF) and other types of PF as follows: paracrine impact, release of leukocyte mediator-1 receptor antagonist, inhibition of the expression of interleukin-1 and tumor necrosis factor-α, and resistant to tissue inflammation,increase of signal transduction for hepatocyte growth factor(HGF),inhibition of PI3K/AKT/mTOR activation and epithelial mesenchymal transformation(EMT) in alveolar Ⅱ epithelial cells(ATⅡ),lung tissue apoptosis and fibrosis, promotion of tissue anti-inflammatory and anti-fibrosis, and to delay organ fibrosis. This review may function as a potential orientation for the treatment of organ fibrosis with MSCs.

Objective To explore the transcriptional alterations regulated by ARID1A in hepatocellular carcinoma cell line PLC/PRF/5. Methods CRISPR/Cas9 technology was utilized to generate ARID1A knockout cells. RNA-seq was then performed in both ARID1A intact and ARID1A null PLC/PRF/5 cells to generate gene expression profiles. Differentially expressed genes were identified using DESeq2. Functional enrichment analysis of differentially expressed genes was performed using metascape database. Results Successful generation of the ARID1A knockout PLC/PRF/5 cells was confirmed by Western blot and Sanger sequencing. A total of 978 differentially expressed genes were identified by RNA-seq, among which the expression of 480 genes was up-regulated and that of 498 genes was down-regulated. These differentially expressed genes were mainly enriched in several biological processes including cell adhesion, regulation of hormone levels, hormone metabolism and regulation of MAP kinase activity. Conclusions The results indicate that ARID1A loss induces alterations in transcription in PLC/PRF/5, which may provide novo clues for elucidating the underlying mechanism of ARID1A in tumorigenesis.

Floral color change in diverse plants has been thought to be a visual signal reflecting changes in floral rewards, promoting pollinator foraging efficiency as well as plant reproductive success. It remains unclear whether olfactory signals co‐vary with floral color change. We investigated the production rhythms of floral scent and nectar associated with floral color change in Lonicera japonica. The flowers generally last 2–3 days. They are white on opening at night (N1) and become light yellow the following day (D1), yellow on the second night (N2), and golden on the second day of flowering (D2). Our measurements in the four stages indicated that nectar production decreased significantly from N1 and D1 to N2 and D2, tracking the floral color change. A total of 34 compounds were detected in floral scent and total scent emission was significantly higher in N2 than in the other three stages. The scent emission of three major compounds, Linalool, cis‐3‐Hexenyl tiglate, and Germacrene D was also significantly higher in N2, but the relative content of Linalool decreased gradually, cis‐3‐Hexenyl tiglate increased gradually, and the relative content of Germacrene D did not differ among the four measured stages. Greater scent emission by night than by day suggested a strong olfactory signal to attract nocturnal hawkmoths, the effective pollinators. However, floral scent rhythms in the four stages did not match the color change and nectar secretion, suggesting that floral color (visual) and scent (olfactory) in this species may play different roles in attracting or filtering various visitors. [ABSTRACT FROM AUTHOR]