Epigenetic marks on histones and DNA,such as DNA methylation at N6-adenine(6mA),play crucial roles in gene expression and genome maintenance,but their deposition and function in microalgae remain largely uncharacteriz...Epigenetic marks on histones and DNA,such as DNA methylation at N6-adenine(6mA),play crucial roles in gene expression and genome maintenance,but their deposition and function in microalgae remain largely uncharacterized.Here,we report a genome-wide 6mA map for the model industrial oleaginous microalga Nannochloropsis oceanica produced by single-molecule real-time sequencing.Found in 0.1%of adenines,6mA sites are mostly enriched at the AGGYV motif,more abundant in transposons and 30 untranslated re-gions,and associated with active transcription.Moreover,6mA gradually increases in abundance along the direction of gene transcription and shows special positional enrichment near splicing donor and transcrip-tion termination sites.Highly expressed genes tend to show greater 6mA abundance in the gene body than do poorly expressed genes,indicating a positive interaction between 6mA and general transcription fac-tors.Furthermore,knockout of the putative 6mA methylase NO08G00280 by genome editing leads to changes in methylation patterns that are correlated with changes in the expression of molybdenum cofactor,sulfate transporter,glycosyl transferase,and lipase genes that underlie reductions in biomass and oil productivity.By contrast,knockout of the candidate demethylase NO06G02500 results in increased 6mA levels and reduced growth.Unraveling the epigenomic players and their roles in biomass productivity and lipid metabolism lays a foundation for epigenetic engineering of industrial microalgae.展开更多
Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups： normal c...Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups： normal control group （NCG） consisted of 8 rats, adenine treated group （ATG） 28 rats, and matrine treated group （MTG） 24 rats. Each rat in ATG and MTG was gavaged with adenine （250 mg·kg^-1·d^-1 ） for 21 d. After gavage with adenine for one week, each rat in MTG was administered intraperitoneally matrine（20 mg·kg^-1·d^-1 ） in vehicle （ 1 mL of 0.9% sodium chloride） daily. On days 14, 21, and 28, the serum levels of urea nitrogen, creatinine, and IL-6 were determined and the rat kidneys of ATG, MTG and NCGwere examined pathologically. Radioimmunoassay for serum IL- 6 immunohistochemical staining for TGF-β1 expression in the kidney and semiquantitative analysis were performed. HE staining for semiquantitative analysis of tubulointerstitial injury. Results The serum levels of urea nitrogen and creatinine in MTG were lower as compare to ATG （ P 〈 0.05 ） whereas serum IL- 6 and renal TGF-β1 expression levels were significantly lower than those in ATG （P 〈0.05 ）, but all these indexes were higher than those in NCG （P 〈 0.01 ）. In MTG, the index of tubulointerstitial lesion was lower than that in ATG （P 〈 0.05 ）. Conclusion Matrine inhibits the renal tubulointerstial fibrosis in the adenine-induced rat model by suppressing serum level of IL-6 and expression of TGF-β1 in the tubulointerstitium.展开更多
The methods of determination of 6-methyl coumarin in cosmetics by HPLC-DAD and GC-FID were compared. The positive samples were confirmed by GC-MS. Methanol was used to extract 6-methyl coumarin from cosmetics. The chr...The methods of determination of 6-methyl coumarin in cosmetics by HPLC-DAD and GC-FID were compared. The positive samples were confirmed by GC-MS. Methanol was used to extract 6-methyl coumarin from cosmetics. The chromatographic conditions of the two methods were optimized and the samples were determined. The recovery, precision, correlation coefficient, detection limit and quantitative limit of the two methods were compared. The results showed that the linear relationship between the two methods was good. The percentage recovery of standard addition by HPLC-DAD was 92.20%~102.80%, by RSD was 0.77%~2.00%;the detection limit was 0.05 mg/kg, the quantitative limit was 0.17 mg/kg. The percentage recovery of standard addition by GC-FID was 97.30%~103.28%, by RSD was 0.47%~4.87%;the detection limit was 1.3 mg/kg, the quantitative limit was 5.0 mg/kg. The detection limit by HPLC-DAD was lower and more sensitive than that by GC-FID , which also shows that HPLC-DAD has more advantages for the detection of low content samples.展开更多
以常规籼稻品种扬稻6号为材料,在盆栽条件下,于生长锥伸长期外喷6-苄基腺嘌呤(6-BA)后,定期取样,测量穗部细胞分裂素(cytok in ins,CKs)含量,同时采用RT-PCR检测水稻穗分化过程中细胞分裂素氧化酶基因(O sCKX2)的表达模式,考察水稻穗部...以常规籼稻品种扬稻6号为材料,在盆栽条件下,于生长锥伸长期外喷6-苄基腺嘌呤(6-BA)后,定期取样,测量穗部细胞分裂素(cytok in ins,CKs)含量,同时采用RT-PCR检测水稻穗分化过程中细胞分裂素氧化酶基因(O sCKX2)的表达模式,考察水稻穗部性状。结果发现:6-BA处理促进水稻穗长发育并显著提高每穗枝梗和颖花数,分化枝梗数和总颖花数分别为60和255.4,比对照分别提高了10%和30.5%。穗部细胞分裂素含量的增加,刺激了更多颖花分化。6-BA处理的水稻穗部O sCKX2表达时间提前,但表达量下降。认为:水稻穗分化始期喷施6-BA可降低穗部O sCKX2的表达强度,提高穗部细胞分裂素含量,对枝梗和颖花分化产生促进作用,为形成大穗提供了先决条件。展开更多
基金supported by the Synthetic Biology Program of the Ministry of Science and Technology of the People’s Republic of China (2021YFA0909700)I201908 and E1551402 from the Qingdao Institute of Bioenergy and Bioprocess Technology,Chinese Academy of Sciences,31900071 from the Natural Science Foundation of ChinaZR2019QC012 from the Natural Science Foundation of Shandong Province.
文摘Epigenetic marks on histones and DNA,such as DNA methylation at N6-adenine(6mA),play crucial roles in gene expression and genome maintenance,but their deposition and function in microalgae remain largely uncharacterized.Here,we report a genome-wide 6mA map for the model industrial oleaginous microalga Nannochloropsis oceanica produced by single-molecule real-time sequencing.Found in 0.1%of adenines,6mA sites are mostly enriched at the AGGYV motif,more abundant in transposons and 30 untranslated re-gions,and associated with active transcription.Moreover,6mA gradually increases in abundance along the direction of gene transcription and shows special positional enrichment near splicing donor and transcrip-tion termination sites.Highly expressed genes tend to show greater 6mA abundance in the gene body than do poorly expressed genes,indicating a positive interaction between 6mA and general transcription fac-tors.Furthermore,knockout of the putative 6mA methylase NO08G00280 by genome editing leads to changes in methylation patterns that are correlated with changes in the expression of molybdenum cofactor,sulfate transporter,glycosyl transferase,and lipase genes that underlie reductions in biomass and oil productivity.By contrast,knockout of the candidate demethylase NO06G02500 results in increased 6mA levels and reduced growth.Unraveling the epigenomic players and their roles in biomass productivity and lipid metabolism lays a foundation for epigenetic engineering of industrial microalgae.
文摘Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups： normal control group （NCG） consisted of 8 rats, adenine treated group （ATG） 28 rats, and matrine treated group （MTG） 24 rats. Each rat in ATG and MTG was gavaged with adenine （250 mg·kg^-1·d^-1 ） for 21 d. After gavage with adenine for one week, each rat in MTG was administered intraperitoneally matrine（20 mg·kg^-1·d^-1 ） in vehicle （ 1 mL of 0.9% sodium chloride） daily. On days 14, 21, and 28, the serum levels of urea nitrogen, creatinine, and IL-6 were determined and the rat kidneys of ATG, MTG and NCGwere examined pathologically. Radioimmunoassay for serum IL- 6 immunohistochemical staining for TGF-β1 expression in the kidney and semiquantitative analysis were performed. HE staining for semiquantitative analysis of tubulointerstitial injury. Results The serum levels of urea nitrogen and creatinine in MTG were lower as compare to ATG （ P 〈 0.05 ） whereas serum IL- 6 and renal TGF-β1 expression levels were significantly lower than those in ATG （P 〈0.05 ）, but all these indexes were higher than those in NCG （P 〈 0.01 ）. In MTG, the index of tubulointerstitial lesion was lower than that in ATG （P 〈 0.05 ）. Conclusion Matrine inhibits the renal tubulointerstial fibrosis in the adenine-induced rat model by suppressing serum level of IL-6 and expression of TGF-β1 in the tubulointerstitium.
文摘The methods of determination of 6-methyl coumarin in cosmetics by HPLC-DAD and GC-FID were compared. The positive samples were confirmed by GC-MS. Methanol was used to extract 6-methyl coumarin from cosmetics. The chromatographic conditions of the two methods were optimized and the samples were determined. The recovery, precision, correlation coefficient, detection limit and quantitative limit of the two methods were compared. The results showed that the linear relationship between the two methods was good. The percentage recovery of standard addition by HPLC-DAD was 92.20%~102.80%, by RSD was 0.77%~2.00%;the detection limit was 0.05 mg/kg, the quantitative limit was 0.17 mg/kg. The percentage recovery of standard addition by GC-FID was 97.30%~103.28%, by RSD was 0.47%~4.87%;the detection limit was 1.3 mg/kg, the quantitative limit was 5.0 mg/kg. The detection limit by HPLC-DAD was lower and more sensitive than that by GC-FID , which also shows that HPLC-DAD has more advantages for the detection of low content samples.
