Osteosarcoma(OS)is the most frequent primary bone sarcomas with high recurrence and poor prognosis.Emerging evidence indicates that membraneless organelles stress granules(SGs),whose assemblies are driven by scaffold ...Osteosarcoma(OS)is the most frequent primary bone sarcomas with high recurrence and poor prognosis.Emerging evidence indicates that membraneless organelles stress granules(SGs),whose assemblies are driven by scaffold protein G3BP1,are extensively involved in tumor,especially in OS.However,how SGs behave and communicate with organelles,particularly nucleoli and mitochondria,during drug challenges remain unknown.This study revealed that chemotherapeutic drugs activated the cysteine protease asparagine endopeptidase(AEP)to specifically cleave the SG core protein G3BP1 at N258/N309 in OS and malignant glioma.tG3BP1-Ns modulated SG dynamics by competitively binding to full-length G3BP1.Strikingly,tG3BP1-Cs,containing a conserved RNA recognition motif CCUBSCUS,sequestered mRNAs of ribosomal proteins and oxidative phosphorylation genes in the nucleoli and mitochondria to repress translation and oxidative stress.Moreover,the inhibition of AEP promoted the tumor-suppressing effect of chemotherapeutic drugs,whereas AEP-cleaved G3BP1 rescue reversed the effect in both OS and glioma models.Cancerous tissues exhibited high levels of AEP and G3BP1 truncations,which were strongly associated with poor prognosis.展开更多
The effects of different concentrations of Zn￣(2+)ion on root growth,cell division,and nucleoli of Allium cepa were studied. The test Zn￣(2+) ion concentration was made up from zinc sulphate (ZnSO4. 7H2O) ranging fr...The effects of different concentrations of Zn￣(2+)ion on root growth,cell division,and nucleoli of Allium cepa were studied. The test Zn￣(2+) ion concentration was made up from zinc sulphate (ZnSO4. 7H2O) ranging from 10￣(-7) to 10￣(-2) mol/L. The solutions were prepared in tap water (pH =6. 5).The results indicated that Zn￣(2+) could obviously inhibit root growth at concentrations from 10￣(-4)to 10￣(-2) mol/L.Roots treated with zinc sulphate showed the presence of c-mitosis, anaphase bridges,including sticky and fluidized bridges (at 10￣(-3) to 10￣(-2) mol/L) , chromosome stickiness, irregularly shaped nuclei, broken nuclei and micronuclei. A toxicity effect was also observed on the nucleoli using silver staining technique after 48h of treatment with 10￣(-4)to 10￣(-2) mol/L Zn￣(2+), e. g,the nucleolar particulate material scattered around the nucleoli in the nucleus of root tip cells.展开更多
Variable Charge X/Y (VCX/Y) is a human testis-specific gene family that localized on X and Y chromosomes. In this study, VCY protein was expressed in E. coli in the form of glutathione-S-transferase (GST) fusion prote...Variable Charge X/Y (VCX/Y) is a human testis-specific gene family that localized on X and Y chromosomes. In this study, VCY protein was expressed in E. coli in the form of glutathione-S-transferase (GST) fusion protein. With the purified fusion protein as antigen, the anti-GST-VCY antibody was generated and the localization of VCY protein in human testis was determined by immunohistochemistry. In the testis seminiferous epithelium. VCY proteins were highly expressed in nuclei of germ cells. Using propidium iodide staining and green fluorescent protein (GFP) tag technologies, VCY and VCX-8r proteins were mainly localized in the uucleoli of COST cells. In addition, the colocalization for VCY and VCX-8r in COS7 cells was also observed. With VCY cDNA as bait, a cDNA fragment of acidic ribosomal protein PO was obtained using yeast two-hybrid system. All the information above indicates that VCX/Y protein family might be involved in the regulation of ribosome assembly (hiring spermatogenesis.展开更多
The nucleolus,the locus of ribosome biogenesis,was found to be the predominant intracellular target of a new fluorescent probe,V-P1.In solution,the probe demonstrated both a selectivity to RNA G-quadruplexes and a sen...The nucleolus,the locus of ribosome biogenesis,was found to be the predominant intracellular target of a new fluorescent probe,V-P1.In solution,the probe demonstrated both a selectivity to RNA G-quadruplexes and a sensitivity to the viscosity,while G-quadruplex binding did not disturb the viscosity sensing.In cells,confocal and fluorescence lifetime imaging,combined with digestion and competition experiments,lent support to the hypothesis of an RNA-based G-quadruplex as the intracellular target,postulated to be nucleolar ribosomal RNA(rRNA).The probe demonstrated a high sensitivity to viscosity in both the cytoplasm and the nuclear compartment and was used to precisely interrogate the viscosity changes resulting from diverse stimuli,such as temperature,monensin treatment,and etoposide-induced apoptosis.Owing to the putative rRNA G-quadruplex binding in vitro and in vivo,and further combined with a relatively low degree of toxicity,the dye enabled the interrogation of cytoplasm and intranuclear viscosity changes under diverse conditions and found applications in studying the influence and significance of cytoplasm and intranuclear viscosity as well as in gaining insight into the native secondary structure of rRNA in nucleoli.展开更多
基金supported by the National Key R&D Program of China(grant number 2023ZD0502206,2024YFB3213200,Topic No.2024YFB3213204)National Natural Science Foundation of China(nos.82273278,82373514,82373202,82272728,82002630,81772654)+5 种基金the National Key Research and Development Program of China(grant number 2022YFC2404602)Shanghai Hospital Development Center Foundation(grant number SHDC12023108)Scientific and Technological Innovation Action Plan of Shanghai Science and Technology Committee(grant number 22Y31900103)Beijing Science and Technology Innovation Medical Development Foundation(grant number KC2021-JX-0170-9)the Shanghai Association for Science and Technology(nos.201409003000,201409002400,20YF1426200)Shanghai Science and Technology Innovation Action Plan(grant number 23Y41900100).
文摘Osteosarcoma(OS)is the most frequent primary bone sarcomas with high recurrence and poor prognosis.Emerging evidence indicates that membraneless organelles stress granules(SGs),whose assemblies are driven by scaffold protein G3BP1,are extensively involved in tumor,especially in OS.However,how SGs behave and communicate with organelles,particularly nucleoli and mitochondria,during drug challenges remain unknown.This study revealed that chemotherapeutic drugs activated the cysteine protease asparagine endopeptidase(AEP)to specifically cleave the SG core protein G3BP1 at N258/N309 in OS and malignant glioma.tG3BP1-Ns modulated SG dynamics by competitively binding to full-length G3BP1.Strikingly,tG3BP1-Cs,containing a conserved RNA recognition motif CCUBSCUS,sequestered mRNAs of ribosomal proteins and oxidative phosphorylation genes in the nucleoli and mitochondria to repress translation and oxidative stress.Moreover,the inhibition of AEP promoted the tumor-suppressing effect of chemotherapeutic drugs,whereas AEP-cleaved G3BP1 rescue reversed the effect in both OS and glioma models.Cancerous tissues exhibited high levels of AEP and G3BP1 truncations,which were strongly associated with poor prognosis.
文摘The effects of different concentrations of Zn￣(2+)ion on root growth,cell division,and nucleoli of Allium cepa were studied. The test Zn￣(2+) ion concentration was made up from zinc sulphate (ZnSO4. 7H2O) ranging from 10￣(-7) to 10￣(-2) mol/L. The solutions were prepared in tap water (pH =6. 5).The results indicated that Zn￣(2+) could obviously inhibit root growth at concentrations from 10￣(-4)to 10￣(-2) mol/L.Roots treated with zinc sulphate showed the presence of c-mitosis, anaphase bridges,including sticky and fluidized bridges (at 10￣(-3) to 10￣(-2) mol/L) , chromosome stickiness, irregularly shaped nuclei, broken nuclei and micronuclei. A toxicity effect was also observed on the nucleoli using silver staining technique after 48h of treatment with 10￣(-4)to 10￣(-2) mol/L Zn￣(2+), e. g,the nucleolar particulate material scattered around the nucleoli in the nucleus of root tip cells.
基金supported by grants from the Special Fund for Major State Basic Research Project(No.G1999055901)National Natural Sciences Foundation of China(No.30240019)+1 种基金National High Technology Research and Technology of China(No.2001AA221131)State Ministry of Science and Technology Program(No.2002BA711A011.
文摘Variable Charge X/Y (VCX/Y) is a human testis-specific gene family that localized on X and Y chromosomes. In this study, VCY protein was expressed in E. coli in the form of glutathione-S-transferase (GST) fusion protein. With the purified fusion protein as antigen, the anti-GST-VCY antibody was generated and the localization of VCY protein in human testis was determined by immunohistochemistry. In the testis seminiferous epithelium. VCY proteins were highly expressed in nuclei of germ cells. Using propidium iodide staining and green fluorescent protein (GFP) tag technologies, VCY and VCX-8r proteins were mainly localized in the uucleoli of COST cells. In addition, the colocalization for VCY and VCX-8r in COS7 cells was also observed. With VCY cDNA as bait, a cDNA fragment of acidic ribosomal protein PO was obtained using yeast two-hybrid system. All the information above indicates that VCX/Y protein family might be involved in the regulation of ribosome assembly (hiring spermatogenesis.
基金supported by CRI project(no.2018R1A3B1052702J.S.K.)from the National Research Foundation of Korea(NRF)+3 种基金by the China Scholarship Fund(CSC no.201907030009L.Y.)by the Interne Fondsen KU Leuven/Internal Funds KU Leuven(STG/19/029P.V.).
文摘The nucleolus,the locus of ribosome biogenesis,was found to be the predominant intracellular target of a new fluorescent probe,V-P1.In solution,the probe demonstrated both a selectivity to RNA G-quadruplexes and a sensitivity to the viscosity,while G-quadruplex binding did not disturb the viscosity sensing.In cells,confocal and fluorescence lifetime imaging,combined with digestion and competition experiments,lent support to the hypothesis of an RNA-based G-quadruplex as the intracellular target,postulated to be nucleolar ribosomal RNA(rRNA).The probe demonstrated a high sensitivity to viscosity in both the cytoplasm and the nuclear compartment and was used to precisely interrogate the viscosity changes resulting from diverse stimuli,such as temperature,monensin treatment,and etoposide-induced apoptosis.Owing to the putative rRNA G-quadruplex binding in vitro and in vivo,and further combined with a relatively low degree of toxicity,the dye enabled the interrogation of cytoplasm and intranuclear viscosity changes under diverse conditions and found applications in studying the influence and significance of cytoplasm and intranuclear viscosity as well as in gaining insight into the native secondary structure of rRNA in nucleoli.
