SKIP is a conserved protein from yeasts to plants and humans. In plant cells, SKIP is a bifunctional regulator that works in the nucleus as a splicing factor by integrating into the spliceosome and as a transcriptiona...SKIP is a conserved protein from yeasts to plants and humans. In plant cells, SKIP is a bifunctional regulator that works in the nucleus as a splicing factor by integrating into the spliceosome and as a transcriptional activator by interacting with the Pall complex. In this study, we identified two nuclear localization signals in SKIP and confirmed that each is sufficient to target SKIP to the nucleus. The SNW domain of SKIP is required for both its function as a splicing factor by promoting integration into the spliceosome in response to stress, and its function as a transcriptional activator by controlling its interaction with the Pall complex to participate in flowering. Truncated proteins that included the SNW domain and the N- or C-terminus of SKIP were still able to carry out the functions of the full-length protein in gene splicing and transcriptional activation in Arabidopsis. In addition, we found that SKIP undergoes 26S proteasome-mediated degrada- tion, and that the C-terminus of SKIP is required to maintain the stability of the protein in plant cells. Together, our findings demonstrate the structural domain organization of SKIP and reveal the core domains and motifs underlying SKIP function in plants.展开更多
[Objectives]To explore the protective effects of flavonoids from Pteridium aquilinum(PAFL)on carbon tetracholoride(CCl_(4))-induced acute liver injury in mice and its potential mechanism.[Methods]All mice were randoml...[Objectives]To explore the protective effects of flavonoids from Pteridium aquilinum(PAFL)on carbon tetracholoride(CCl_(4))-induced acute liver injury in mice and its potential mechanism.[Methods]All mice were randomly divided into four groups(n=10 in each),normal group,CCl_(4)group,CCl_(4)+PAFL groups[treated with PAFL(50 or 200 mg/kg)].Animal treatment was continued for 7 consecutive days.The blood was collected after injection of CCl_(4)for 24 h,and the liver tissue was removed from the mice and stored at-80℃.[Results]The PAFL(50 and 200 mg/kg)significantly inhibited the increase of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels in serum caused by CCl_(4)treatment.PAFL administration not only increased the activity of antioxidant enzymes superoxide dismutase(SOD),Glutathione(GSH)and catalase(CAT)in mice,but also reduced the level of malondialdehyde(MDA).Meanwhile,PAFL administration decreased the expression of nuclear factor-kappa B(NF-κB)and Cyclooxygenase-2(COX-2)proteins and inhibited the release of pro-inflammatory factors tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin 6(IL-6).In addition,PAFL(200 mg/kg)treatment down-regulated extracellular regulated protein kinases(ERK)and c-Jun N-terminal kinase(JNK)protein levels in liver tissue.[Conclusions]These findings clearly indicate that the protective effects of PAFL on CCl_(4)-induced acute liver injury is related to its antioxidant and anti-inflammatory activity,which may be mediated by NF-κB and MAPKs signaling pathways.展开更多
文摘SKIP is a conserved protein from yeasts to plants and humans. In plant cells, SKIP is a bifunctional regulator that works in the nucleus as a splicing factor by integrating into the spliceosome and as a transcriptional activator by interacting with the Pall complex. In this study, we identified two nuclear localization signals in SKIP and confirmed that each is sufficient to target SKIP to the nucleus. The SNW domain of SKIP is required for both its function as a splicing factor by promoting integration into the spliceosome in response to stress, and its function as a transcriptional activator by controlling its interaction with the Pall complex to participate in flowering. Truncated proteins that included the SNW domain and the N- or C-terminus of SKIP were still able to carry out the functions of the full-length protein in gene splicing and transcriptional activation in Arabidopsis. In addition, we found that SKIP undergoes 26S proteasome-mediated degrada- tion, and that the C-terminus of SKIP is required to maintain the stability of the protein in plant cells. Together, our findings demonstrate the structural domain organization of SKIP and reveal the core domains and motifs underlying SKIP function in plants.
基金This work was partly supported by the National Natural Science Foundation of Jiangsu Province (No. BK2005028) and the NationalNatural Science Foundation of China (No. 30140007).
基金the Innovation Project of Jilin Academy of Agricultural Sciences(CXGC2017ZY011)Major Project of Jilin Provincial Department of Science and Technology(20170204046NY)。
文摘[Objectives]To explore the protective effects of flavonoids from Pteridium aquilinum(PAFL)on carbon tetracholoride(CCl_(4))-induced acute liver injury in mice and its potential mechanism.[Methods]All mice were randomly divided into four groups(n=10 in each),normal group,CCl_(4)group,CCl_(4)+PAFL groups[treated with PAFL(50 or 200 mg/kg)].Animal treatment was continued for 7 consecutive days.The blood was collected after injection of CCl_(4)for 24 h,and the liver tissue was removed from the mice and stored at-80℃.[Results]The PAFL(50 and 200 mg/kg)significantly inhibited the increase of aspartate aminotransferase(AST)and alanine aminotransferase(ALT)levels in serum caused by CCl_(4)treatment.PAFL administration not only increased the activity of antioxidant enzymes superoxide dismutase(SOD),Glutathione(GSH)and catalase(CAT)in mice,but also reduced the level of malondialdehyde(MDA).Meanwhile,PAFL administration decreased the expression of nuclear factor-kappa B(NF-κB)and Cyclooxygenase-2(COX-2)proteins and inhibited the release of pro-inflammatory factors tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β)and interleukin 6(IL-6).In addition,PAFL(200 mg/kg)treatment down-regulated extracellular regulated protein kinases(ERK)and c-Jun N-terminal kinase(JNK)protein levels in liver tissue.[Conclusions]These findings clearly indicate that the protective effects of PAFL on CCl_(4)-induced acute liver injury is related to its antioxidant and anti-inflammatory activity,which may be mediated by NF-κB and MAPKs signaling pathways.
