In eukaryotic cells,both alternative splicing and alternative polyadenylation(APA)play essential roles in the gene regulation network.U1 small ribonucleoprotein particle(U1 snRNP)is a major component of spliceosome,an...In eukaryotic cells,both alternative splicing and alternative polyadenylation(APA)play essential roles in the gene regulation network.U1 small ribonucleoprotein particle(U1 snRNP)is a major component of spliceosome,and U1 snRNP complex can suppress proximal APA sites through crosstalking with 3end processing factors.However,here we show that both knockdown and overexpression of SNRPA,SNRPC,SNRNP70,and SNRPD2,the U1 snRNP proteins,promote the usage of proximal APA sites at the transcriptome level.SNRNP70 can drive the phase transition of PABPN1 from droplet to aggregate,which may reduce the repressive effects of PABPN1 on the proximal APA sites.Additionally,SNRNP70 can also promote the proximal APA sites by recruiting CPSF6,suggesting that the function of CPSF6 on APA is related with other RNA-binding proteins and cell context-dependent.Consequently,these results reveal that,on the contrary to U1 snRNP complex,the free proteins of U1 snRNP complex can promote proximal APA sites through the interaction with 3end processing machinery.展开更多
Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the ...Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the RACE method. And it is identified by Northern blotting that its expression is special in vernalization treatment. After comparing the sequence in the nucleotide sequence databases of Genbank, EMBL and DDBJ, the gene has homology with Hordeum vulgare jesmonate-induced protein gene. It is suggested that this gene might be related to the signal transduction mediated by jamonate.展开更多
A theoretical model to simulate an end-pumped CW Nd^3＋：GdVO4 laser at 1063 nm is presented. Its essence is to use the propagation equations to demonstrate the spatial evolutions of the pump and the laser powers in t...A theoretical model to simulate an end-pumped CW Nd^3＋：GdVO4 laser at 1063 nm is presented. Its essence is to use the propagation equations to demonstrate the spatial evolutions of the pump and the laser powers in the cavity, hence it is applicable to both low and high gain lasers. The simulation results obtained by this model are in good agreement with the experimental observations reported in the literature for a Ti：sapphlre-pumped Nd^3＋：GdVO4 laser. Moreover, some parameters, such as the reflectivity of output coupler, the spot size of laser beam and the crystal length, are discussed with a view to optimizing the laser performance.展开更多
基金supported by the National Natural Science Foundation of China(31971332 to Y.F.,91942301 and 81430099 to A.X,and 32000450 to L.C.).
文摘In eukaryotic cells,both alternative splicing and alternative polyadenylation(APA)play essential roles in the gene regulation network.U1 small ribonucleoprotein particle(U1 snRNP)is a major component of spliceosome,and U1 snRNP complex can suppress proximal APA sites through crosstalking with 3end processing factors.However,here we show that both knockdown and overexpression of SNRPA,SNRPC,SNRNP70,and SNRPD2,the U1 snRNP proteins,promote the usage of proximal APA sites at the transcriptome level.SNRNP70 can drive the phase transition of PABPN1 from droplet to aggregate,which may reduce the repressive effects of PABPN1 on the proximal APA sites.Additionally,SNRNP70 can also promote the proximal APA sites by recruiting CPSF6,suggesting that the function of CPSF6 on APA is related with other RNA-binding proteins and cell context-dependent.Consequently,these results reveal that,on the contrary to U1 snRNP complex,the free proteins of U1 snRNP complex can promote proximal APA sites through the interaction with 3end processing machinery.
文摘Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the RACE method. And it is identified by Northern blotting that its expression is special in vernalization treatment. After comparing the sequence in the nucleotide sequence databases of Genbank, EMBL and DDBJ, the gene has homology with Hordeum vulgare jesmonate-induced protein gene. It is suggested that this gene might be related to the signal transduction mediated by jamonate.
基金supported by the National Natural Science Foundation of China (Grant No 10104009)
文摘A theoretical model to simulate an end-pumped CW Nd^3＋：GdVO4 laser at 1063 nm is presented. Its essence is to use the propagation equations to demonstrate the spatial evolutions of the pump and the laser powers in the cavity, hence it is applicable to both low and high gain lasers. The simulation results obtained by this model are in good agreement with the experimental observations reported in the literature for a Ti：sapphlre-pumped Nd^3＋：GdVO4 laser. Moreover, some parameters, such as the reflectivity of output coupler, the spot size of laser beam and the crystal length, are discussed with a view to optimizing the laser performance.
