There can be found some notable discrepancies with regard to the resonance structures when R-matrix calculations from the Opacity Project and other sources are compared with recent absolute experimental measurements o...There can be found some notable discrepancies with regard to the resonance structures when R-matrix calculations from the Opacity Project and other sources are compared with recent absolute experimental measurements of Bizau et al [Astron. Astrophts. 439 387 （2005）] for B-like ions N^2＋, O^3＋ and F^4＋. We performed close-coupling calculations based on the R-matrix formalism for the photoionizations of ions mentioned above both for the ground states and first excited states in the near threshold regions. The present results are compared with experimental ones given by Bizau et al and earlier theoretical ones. Excellent agreement is obtained between our theoretical results and the experimental photoionization cross sections. The present calculations show a significant improvement over the previous theoretical results.展开更多
The N^(6)-methyladenosine(m^(6)A)modification is the most prevalent modification of eukaryotic mRNAs and plays a crucial role in various physiological processes by regulating the stability or function of target mRNAs....The N^(6)-methyladenosine(m^(6)A)modification is the most prevalent modification of eukaryotic mRNAs and plays a crucial role in various physiological processes by regulating the stability or function of target mRNAs.Accumulating evidence has suggested that m6A methylation may be involved in the pathological process of major depressive disorder(MDD),a common neuropsychiatric disorder with an unclear aetiology.Here,we found that the levels of the circular RNA HECW2(circHECW2)were significantly increased in the plasma of both MDD patients and the chronic unpredictable stress(CUS)mouse model.Notably,the downregulation of circHECW2 attenuated astrocyte dysfunction and depression-like behaviors induced by CUS.Furthermore,we demonstrated that the downregulation of circHECW2 increased the expression of the methylase WTAP,leading to an increase in Gng4 expression via m^(6)A modifications.Our findings provide functional insight into the correlation between circHECW2 and m^(6)A methylation,suggesting that circHECW2 may represent a potential target for MDD treatment.展开更多
Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress ...Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress response.However,its existence in eukaryotic mRNAs is still controversial.In plants,the existence,distribution pattern,and potential function of RNA ac^(4)C modification are largely unknown.Here we report the presence of ac^(4)C in the mRNAs of both Arabidopsis thaliana and rice(Oryza sativa).By comparing two ac^(4)C sequencing methods,we found that RNA immunoprecipitation and sequencing(acRIP-seq),but not ac^(4)C sequencing,was suitable for plant RNA ac^(4)C sequencing.We present transcriptome-wide atlases of RNA ac^(4)C modification in A.thaliana and rice mRNAs obtained by acRIP-seq.Analysis of the distribution of RNA ac^(4)C modifications showed that ac^(4)C is enriched near translation start sites in rice mRNAs and near translation start sites and translation end sites in Arabidopsis mRNAs.The RNA ac^(4)C modification level is positively correlated with RNA half-life and the number of splicing variants.Similar to that in mammals,the translation efficiency of ac^(4)C target genes is significantly higher than that of other genes.Our in vitro translation results confirmed that RNA ac^(4)C modification enhances translation efficiency.We also found that RNA ac^(4)C modification is negatively correlated with RNA structure.These results suggest that ac^(4)C is a conserved mRNA modification in plants that contributes to RNA stability,splicing,translation,and secondary structure formation.展开更多
基金supported by the National Natural Science Foundation of China (Grant No 10674112)the Natural Science Foundation of the Gansu Province,China (Grant No 3ZS061-A25-013)+2 种基金the Foundation of Education Department of Gansu Province,China (Grant No 0601223)the Foundation of Northwest Normal University,China (Grant No NWNU-KJCXGC-03-21)the Foundation for Young Teacher of Northwest Normal University,China (Grant No NWNU-LKQN-08-5)
文摘There can be found some notable discrepancies with regard to the resonance structures when R-matrix calculations from the Opacity Project and other sources are compared with recent absolute experimental measurements of Bizau et al [Astron. Astrophts. 439 387 （2005）] for B-like ions N^2＋, O^3＋ and F^4＋. We performed close-coupling calculations based on the R-matrix formalism for the photoionizations of ions mentioned above both for the ground states and first excited states in the near threshold regions. The present results are compared with experimental ones given by Bizau et al and earlier theoretical ones. Excellent agreement is obtained between our theoretical results and the experimental photoionization cross sections. The present calculations show a significant improvement over the previous theoretical results.
基金This work was supported by grants from the Science and Technology Innovation 2030-Major Project of the Ministry of Science and Technology of China(2021ZD0202904/2021ZD0202900)the National Science Fund Distinguished Young Scholars(82025033,China)+4 种基金the National Natural Science Foundation of China(82230115,82273914,81903591,82372024,82003733)the Natural Science Foundation of Jiangsu Province(BK20200358,China)ZhiShan Scholar Program of Southeast University(2242022R40059 and 2242021R40023,China)the Jiangsu Provincial Key Laboratory of Critical Care Medicine(JSKLCCM-2022-02-008,China)the Open Project Program of the Key Laboratory of Developmental Genes and Human Diseases of the Ministry of Education(LDGHD202304,China).
文摘The N^(6)-methyladenosine(m^(6)A)modification is the most prevalent modification of eukaryotic mRNAs and plays a crucial role in various physiological processes by regulating the stability or function of target mRNAs.Accumulating evidence has suggested that m6A methylation may be involved in the pathological process of major depressive disorder(MDD),a common neuropsychiatric disorder with an unclear aetiology.Here,we found that the levels of the circular RNA HECW2(circHECW2)were significantly increased in the plasma of both MDD patients and the chronic unpredictable stress(CUS)mouse model.Notably,the downregulation of circHECW2 attenuated astrocyte dysfunction and depression-like behaviors induced by CUS.Furthermore,we demonstrated that the downregulation of circHECW2 increased the expression of the methylase WTAP,leading to an increase in Gng4 expression via m^(6)A modifications.Our findings provide functional insight into the correlation between circHECW2 and m^(6)A methylation,suggesting that circHECW2 may represent a potential target for MDD treatment.
基金support from the National Natural Science Foundation of China(32070613,32270623)the Science and Technology Innovation Program of Hunan Province(2021RC3045)+1 种基金support from the National Natural Science Foundation of China(U20A2029)support from the Postgraduate Scientific Research Innovation Project of Hunan Province(CX20200468).
文摘Acetylation of N^(4)-cytidine(ac^(4)C)has recently been discovered as a novel modification of mRNA.RNA ac^(4)C modification has been shown to be a key regulator of RNA stability,RNA translation,and the thermal stress response.However,its existence in eukaryotic mRNAs is still controversial.In plants,the existence,distribution pattern,and potential function of RNA ac^(4)C modification are largely unknown.Here we report the presence of ac^(4)C in the mRNAs of both Arabidopsis thaliana and rice(Oryza sativa).By comparing two ac^(4)C sequencing methods,we found that RNA immunoprecipitation and sequencing(acRIP-seq),but not ac^(4)C sequencing,was suitable for plant RNA ac^(4)C sequencing.We present transcriptome-wide atlases of RNA ac^(4)C modification in A.thaliana and rice mRNAs obtained by acRIP-seq.Analysis of the distribution of RNA ac^(4)C modifications showed that ac^(4)C is enriched near translation start sites in rice mRNAs and near translation start sites and translation end sites in Arabidopsis mRNAs.The RNA ac^(4)C modification level is positively correlated with RNA half-life and the number of splicing variants.Similar to that in mammals,the translation efficiency of ac^(4)C target genes is significantly higher than that of other genes.Our in vitro translation results confirmed that RNA ac^(4)C modification enhances translation efficiency.We also found that RNA ac^(4)C modification is negatively correlated with RNA structure.These results suggest that ac^(4)C is a conserved mRNA modification in plants that contributes to RNA stability,splicing,translation,and secondary structure formation.
