This study examines inhibiting galectin 1(Gal1)as a treatment option for hepatocellular carcinoma(HCC).Gal1 has immunosuppressive and cancer-promoting roles.Our data showed that Gal1 was highly expressed in human and ...This study examines inhibiting galectin 1(Gal1)as a treatment option for hepatocellular carcinoma(HCC).Gal1 has immunosuppressive and cancer-promoting roles.Our data showed that Gal1 was highly expressed in human and mouse HCC.The levels of Gal1 positively correlated with the stages of human HCC and negatively with survival.The roles of Gal1 in HCC were studied using overexpression(OE)or silencing using Igals1 siRNA delivered by AAV9.Prior to HCC initiation induced by RAS and AKT mutations,lgals1-OE and silencing had opposite impacts on tumor load.The treatment effect of lgals1 siRNAwas further demonstrated by intersecting HCC at different time points when the tumor load had already reached 9%or even 42%of the body weight.Comparing spatial transcriptomic profiles of Gal1 silenced and OE HCC,inhibiting matrix formation and recognition of foreign antigen in CD45t cell-enriched areas located at tumor-margin likely contributed to the anti-HCC effects of Gal1 silencing.Within the tumors,silencing Gal1 inhibited translational initiation,elongation,and termination.Furthermore,Gal1 silencing increased immune cells as well as expanded cytotoxic T cells within the tumor,and the anti-HCC effect of lgals1 siRNAwas CD8-dependent.Overall,Gal1 silencing has a promising potential for HCC treatment.展开更多
In order to find new insect resistance genes, four homologous cDNAs, hta-a, hta-b, hta-c and hta-d with lengths of 775, 718, 784 and 752 bp, respectively （GenBank accession numbers AF477031-AF477034）, were iso...In order to find new insect resistance genes, four homologous cDNAs, hta-a, hta-b, hta-c and hta-d with lengths of 775, 718, 784 and 752 bp, respectively （GenBank accession numbers AF477031-AF477034）, were isolated from a tuber cDNA expression library of Helianthus tuberosus L. Sequence analysis revealed that all four cDNAs contain an open reading frame of 444 bp, coding a polypeptide of 147 amino acid residues, and that the sequences of the cDNAs are very similar to those of the mannose-binding agglutinin genes of the jacalin-related family. In hemagglutination reactions and hapten inhibition assays, affinity-purified HTA （Helianthus tuberosus agglutinin） from induced Escherichia coli BL21（DE3） expressing GST-HTA shows hemagglutination ability and a higher carbohydrate-binding ability for mannose than other tested sugars. Trypsin inhibitory activity was detected in the crude extracts of induced E. coli BL21（DE3） expressing HTA, and was further verified by trypsin inhibitory activity staining on native polyacrylamide gel. The mechanism of interaction between HTA and trypsin was studied by molecular modeling. We found that plenty of hydrogen bonds and electrostatic interactions can be formed between the supposed binding sites of HTA-b and the active site of trypsin, and that a stable HTA/trypsin complex can be formed. The results above imply that HTA might be a bifunctional protein with carbohydrate-binding activity and trypsin inhibitory activity. Moreover, Northern blotting analysis demonstrated that hta is predominantly expressed in tubers of H. tuberosus, very weakly expressed in stems, but not expressed at all in other tissues. Southern blotting analysis indicated that hta is encoded by a multi-gene family. The insect resistance traits have been described in another paper.展开更多
Enzymes have high activity at low temperatures are defined as cold-adapted enzymes,but few enzymes show an activation effect after low-temperature incubation.In this study,we cloned an agarase from the marine bacte-ri...Enzymes have high activity at low temperatures are defined as cold-adapted enzymes,but few enzymes show an activation effect after low-temperature incubation.In this study,we cloned an agarase from the marine bacte-rium Catenovulum agarivorans STB13(Ca-AGA)and expressed the protein in Bacillus subtilis.The enzyme exhibited a peculiar cold activation,which was enhanced by 5-fold after incubation at-20℃ or 4℃ for 6 h.Fluorescence and CD spectra studies confirmed the secondary and tertiary structural changes in Ca-AGA at low temperature,which formed compact protein structures after low-temperature treatment.The enzyme also showed outstanding cold adaptation,retaining approximately 60%of its maximum activity at 10℃.Based on a bioinformatics analysis,the carbohydrate-binding modules(CBMs)and long linker region were presumed to play a crucial role in cold adaptation due to a relatively high percentage of acidic residues and a negative charge density compared to the catalytic domain.A mutation that truncated the linker-CBM region resulted in a 59.97%reduction of the activity at 10℃.This study describes anα-agarase of cold activation and adaptation in detail,which may have great potential for producing functional agaro-oligosaccharides in food and pharmaceutical industrial applications at ambient temperature.展开更多
Griffonia simplicifolia lectin II （GSII） and wheat germ agglutinin （WGA） are N-acetylglucosamine-binding lectins. Previous studies demonstrated that they have anti- insect activity, a property potentially useful i...Griffonia simplicifolia lectin II （GSII） and wheat germ agglutinin （WGA） are N-acetylglucosamine-binding lectins. Previous studies demonstrated that they have anti- insect activity, a property potentially useful in pest control. To gain some insight into the insect response to dietary lectins, we performed transcriptomic analysis using the cowpea bruchid （Callosobruchus maculatus） midgut microarray platform we built. Compared to the normutritional cellulose treatment, dietary lectins induced more profound changes in gene expression. Ingestion of relatively high doses oflectins for 24 h resulted in alteration of gene expression involved in sugar and lipid metabolism, transport, development, defense, and stress tolerance. Metabolic genes were largely downregulated. Moreover, we observed disorganized microvilli resulting from ingestion of WGA. This morphological change is consistent with the lectin-induced changes in genes related to midgut epithelial cell repair. In addition, suboptimal nutrient conditions may serve as a stress signal to trigger senescence processes, leading to growth arrest and developmental delay.展开更多
基金The authors thank the Genomics Shared Resource(GSR)core facility at the University of California,Davis Health,Dr.Clifford G Tepper,Stephanie Liu,Ryan Davis,for helping in performing spatial RNA sequencing,and William Amato for his assistance in the quantification of immunohistochemistry slides.This manuscript is supported by grants funded by the USA National Institutes of Health(NIH)T32 CA108459e15,R01CA222490,R50CA243787.BioRender was used to draw mice figures in schematic experimental design.
文摘This study examines inhibiting galectin 1(Gal1)as a treatment option for hepatocellular carcinoma(HCC).Gal1 has immunosuppressive and cancer-promoting roles.Our data showed that Gal1 was highly expressed in human and mouse HCC.The levels of Gal1 positively correlated with the stages of human HCC and negatively with survival.The roles of Gal1 in HCC were studied using overexpression(OE)or silencing using Igals1 siRNA delivered by AAV9.Prior to HCC initiation induced by RAS and AKT mutations,lgals1-OE and silencing had opposite impacts on tumor load.The treatment effect of lgals1 siRNAwas further demonstrated by intersecting HCC at different time points when the tumor load had already reached 9%or even 42%of the body weight.Comparing spatial transcriptomic profiles of Gal1 silenced and OE HCC,inhibiting matrix formation and recognition of foreign antigen in CD45t cell-enriched areas located at tumor-margin likely contributed to the anti-HCC effects of Gal1 silencing.Within the tumors,silencing Gal1 inhibited translational initiation,elongation,and termination.Furthermore,Gal1 silencing increased immune cells as well as expanded cytotoxic T cells within the tumor,and the anti-HCC effect of lgals1 siRNAwas CD8-dependent.Overall,Gal1 silencing has a promising potential for HCC treatment.
基金Supported by the State Key Basic Research and Development Plan of China(G2000016205)the Hi-Tech Research and Development(863) Program of China(2001AA212041)+2 种基金the National Special Program for Research and Industrialization of Transgenic Plants(J99-B-004)the Rockefeller Foundation,the International Program on Rice Biotechnology(RF 97042 #14)the Special Supporting Program of the Chinese Academy of Sciences(STZ98-3-08)
文摘In order to find new insect resistance genes, four homologous cDNAs, hta-a, hta-b, hta-c and hta-d with lengths of 775, 718, 784 and 752 bp, respectively （GenBank accession numbers AF477031-AF477034）, were isolated from a tuber cDNA expression library of Helianthus tuberosus L. Sequence analysis revealed that all four cDNAs contain an open reading frame of 444 bp, coding a polypeptide of 147 amino acid residues, and that the sequences of the cDNAs are very similar to those of the mannose-binding agglutinin genes of the jacalin-related family. In hemagglutination reactions and hapten inhibition assays, affinity-purified HTA （Helianthus tuberosus agglutinin） from induced Escherichia coli BL21（DE3） expressing GST-HTA shows hemagglutination ability and a higher carbohydrate-binding ability for mannose than other tested sugars. Trypsin inhibitory activity was detected in the crude extracts of induced E. coli BL21（DE3） expressing HTA, and was further verified by trypsin inhibitory activity staining on native polyacrylamide gel. The mechanism of interaction between HTA and trypsin was studied by molecular modeling. We found that plenty of hydrogen bonds and electrostatic interactions can be formed between the supposed binding sites of HTA-b and the active site of trypsin, and that a stable HTA/trypsin complex can be formed. The results above imply that HTA might be a bifunctional protein with carbohydrate-binding activity and trypsin inhibitory activity. Moreover, Northern blotting analysis demonstrated that hta is predominantly expressed in tubers of H. tuberosus, very weakly expressed in stems, but not expressed at all in other tissues. Southern blotting analysis indicated that hta is encoded by a multi-gene family. The insect resistance traits have been described in another paper.
基金financially supported by the National Key R&D Pro-gram of China(2019YFD0901901)the National Natural Science Foundation of China(No.32272263)Science and Technology Support Program(Modern Agriculture)of Jiangsu Province(BE2022323).
文摘Enzymes have high activity at low temperatures are defined as cold-adapted enzymes,but few enzymes show an activation effect after low-temperature incubation.In this study,we cloned an agarase from the marine bacte-rium Catenovulum agarivorans STB13(Ca-AGA)and expressed the protein in Bacillus subtilis.The enzyme exhibited a peculiar cold activation,which was enhanced by 5-fold after incubation at-20℃ or 4℃ for 6 h.Fluorescence and CD spectra studies confirmed the secondary and tertiary structural changes in Ca-AGA at low temperature,which formed compact protein structures after low-temperature treatment.The enzyme also showed outstanding cold adaptation,retaining approximately 60%of its maximum activity at 10℃.Based on a bioinformatics analysis,the carbohydrate-binding modules(CBMs)and long linker region were presumed to play a crucial role in cold adaptation due to a relatively high percentage of acidic residues and a negative charge density compared to the catalytic domain.A mutation that truncated the linker-CBM region resulted in a 59.97%reduction of the activity at 10℃.This study describes anα-agarase of cold activation and adaptation in detail,which may have great potential for producing functional agaro-oligosaccharides in food and pharmaceutical industrial applications at ambient temperature.
基金Acknowledgments We thank Dr. Ron Salzman for his critical review of this manuscript. This project was supported by the USDA National Research Initiative grant# 2005-35604-15438, by the Natural Science Foundation of Jiangsu Province （BK20130711）, and by Basic Science Research Program through the NRF of Korea funded by the MOEST （2012R1A1A2044114）.
文摘Griffonia simplicifolia lectin II （GSII） and wheat germ agglutinin （WGA） are N-acetylglucosamine-binding lectins. Previous studies demonstrated that they have anti- insect activity, a property potentially useful in pest control. To gain some insight into the insect response to dietary lectins, we performed transcriptomic analysis using the cowpea bruchid （Callosobruchus maculatus） midgut microarray platform we built. Compared to the normutritional cellulose treatment, dietary lectins induced more profound changes in gene expression. Ingestion of relatively high doses oflectins for 24 h resulted in alteration of gene expression involved in sugar and lipid metabolism, transport, development, defense, and stress tolerance. Metabolic genes were largely downregulated. Moreover, we observed disorganized microvilli resulting from ingestion of WGA. This morphological change is consistent with the lectin-induced changes in genes related to midgut epithelial cell repair. In addition, suboptimal nutrient conditions may serve as a stress signal to trigger senescence processes, leading to growth arrest and developmental delay.
