AIM: To investigate the impact of hepatitis B virus (HBV) infection on cellular gene expression, by conducting both in vitro and in vivo studies. METHODS: Knockdown of HBV was targeted by stable expression of short ha...AIM: To investigate the impact of hepatitis B virus (HBV) infection on cellular gene expression, by conducting both in vitro and in vivo studies. METHODS: Knockdown of HBV was targeted by stable expression of short hairpin RNA (shRNA) in huH-1 cells. Cellular gene expression was compared using a human 30K cDNA microarray in the cells and quantified by real-time reverse transcription-polymerase chain reaction (RT-PCR) (qRT-PCR) in the cells, hepatocellular carcinoma (HCC) and surrounding non-cancerous liver tissues (SL). RESULTS: The expressions of HBsAg and HBx protein were markedly suppressed in the cells and in HBx transgenic mouse liver, respectively, after introduction of shRNA. Of the 30K genes studied, 135 and 103 genes were identified as being down- and up-regulated, respectively, by at least twofold in the knockdown cells. Functional annotation revealed that 85 and 62 genes were classified into four up-regulated and five down-regulated functional categories, respectively. When gene expression levels were compared between HCC and SL, eight candidate genes that were confirmed to be up- or down-regulated in the knockdown cells by both microarray and qRT-PCR analyses were not expressed as expected from HBV reduction in HCC, but had similar expression patterns in HBV- and hepatitis C virus-associated cases. In contrast, among the eight genes, only APM2 was constantly repressed in HBV non-associated tissues irrespective of HCC or SL. CONCLUSION: The signature of cellular gene expression should provide new information regarding the pathophysiological mechanisms of persistent hepatitis and hepatocarcinogenesis that are associated with HBV infection.展开更多
To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, fulllength cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtai...To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, fulllength cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtained from the anthers of a Capsicum annuum nuclear male-fertile line. Sequence analysis indicated that the full length of CaMF5 was 747 bp, containing a maximum opening reading frame of 447 bp.Amino acid sequence alignment and phylogenetic analysis revealed that CaMF5 shared approximately 37%–77% homology with a series of uncharacterized or hypothetical proteins and late embryogenesis abundant(LEA) proteins from other plants. However, no LEA structural domain was detected in CaMF5, which indicated that it might be a new type of LEA gene. CaMF5 was only expressed in flower buds at stages 7 and 8 and in open flowers of the male-fertile line, whereas it exhibited no expression in any examined organs of the male-sterile line. In addition, CaMF5 showed the highest transcript abundance in the anthers of the male-fertile line, with no expression being detected in any other examined organs, such as the sepals, petals, pistils, roots, stems, or leaves. Taken together, our results suggest that CaMF5 is an anther-specific gene that might encode a new type of LEA protein related to anther and/or pollen development in C. annuum.展开更多
Rapid,precise,and tunable regulation of protein abundance would be significantly useful in a variety of biotechnologies and biomedical applications.Here,we describe a system that allows tunable and rapid drug control ...Rapid,precise,and tunable regulation of protein abundance would be significantly useful in a variety of biotechnologies and biomedical applications.Here,we describe a system that allows tunable and rapid drug control of gene expression for either gene activation or inactivation in mammalian cells.We construct the system by coupling Tet-on 3 G and small molecule-assisted shutoff systems,which can respectively induce transcriptional activation and protein degradation in the presence of corresponding small molecules.This dual-input drug inducer regulation system facilitates a bidirectional control of gene expression.The gene of interest can be precisely controlled by dual small molecules in a broad dynamic range of expression from overexpression to complete silence,allowing gene function study in a comprehensive expression profile.Our results reveal that the bidirectional control system enables sensitive dosage-and time-dependent regulation for either turn-on or shutoff of gene expression.We also apply this system for inducible genome editing and gene activation mediated by clustered regularly interspaced short palindromic repeats.The system provides an integrated platform for studying multiple biological processes by manipulating gene expression in a more flexible way.展开更多
文摘AIM: To investigate the impact of hepatitis B virus (HBV) infection on cellular gene expression, by conducting both in vitro and in vivo studies. METHODS: Knockdown of HBV was targeted by stable expression of short hairpin RNA (shRNA) in huH-1 cells. Cellular gene expression was compared using a human 30K cDNA microarray in the cells and quantified by real-time reverse transcription-polymerase chain reaction (RT-PCR) (qRT-PCR) in the cells, hepatocellular carcinoma (HCC) and surrounding non-cancerous liver tissues (SL). RESULTS: The expressions of HBsAg and HBx protein were markedly suppressed in the cells and in HBx transgenic mouse liver, respectively, after introduction of shRNA. Of the 30K genes studied, 135 and 103 genes were identified as being down- and up-regulated, respectively, by at least twofold in the knockdown cells. Functional annotation revealed that 85 and 62 genes were classified into four up-regulated and five down-regulated functional categories, respectively. When gene expression levels were compared between HCC and SL, eight candidate genes that were confirmed to be up- or down-regulated in the knockdown cells by both microarray and qRT-PCR analyses were not expressed as expected from HBV reduction in HCC, but had similar expression patterns in HBV- and hepatitis C virus-associated cases. In contrast, among the eight genes, only APM2 was constantly repressed in HBV non-associated tissues irrespective of HCC or SL. CONCLUSION: The signature of cellular gene expression should provide new information regarding the pathophysiological mechanisms of persistent hepatitis and hepatocarcinogenesis that are associated with HBV infection.
基金supported by the Guangdong Key Research and Development Program (2018B020202010)National Natural Science Foundation of China (31572124)+1 种基金Key Project of Guangdong Science and Technology Department (2015B020202009)the Key Project of Guangzhou Science and Technology Program (201508030021)
文摘To improve the understanding of molecular mechanisms of anther and/or pollen development in Chili pepper, in the present study, fulllength cDNA and DNA sequences of the pollen development-related gene CaMF5 were obtained from the anthers of a Capsicum annuum nuclear male-fertile line. Sequence analysis indicated that the full length of CaMF5 was 747 bp, containing a maximum opening reading frame of 447 bp.Amino acid sequence alignment and phylogenetic analysis revealed that CaMF5 shared approximately 37%–77% homology with a series of uncharacterized or hypothetical proteins and late embryogenesis abundant(LEA) proteins from other plants. However, no LEA structural domain was detected in CaMF5, which indicated that it might be a new type of LEA gene. CaMF5 was only expressed in flower buds at stages 7 and 8 and in open flowers of the male-fertile line, whereas it exhibited no expression in any examined organs of the male-sterile line. In addition, CaMF5 showed the highest transcript abundance in the anthers of the male-fertile line, with no expression being detected in any other examined organs, such as the sepals, petals, pistils, roots, stems, or leaves. Taken together, our results suggest that CaMF5 is an anther-specific gene that might encode a new type of LEA protein related to anther and/or pollen development in C. annuum.
基金supported by the National Natural Science Foundation of China(81800555,81701580,and 31972926)the National Key R&D Program of China(2018YFC1106400)+1 种基金the Science and Technology Planning Project of Guangdong Province(2015B020229002)the Natural Science Foundation of Guangdong Province(2014A030312013 and 2018A030313128)
文摘Rapid,precise,and tunable regulation of protein abundance would be significantly useful in a variety of biotechnologies and biomedical applications.Here,we describe a system that allows tunable and rapid drug control of gene expression for either gene activation or inactivation in mammalian cells.We construct the system by coupling Tet-on 3 G and small molecule-assisted shutoff systems,which can respectively induce transcriptional activation and protein degradation in the presence of corresponding small molecules.This dual-input drug inducer regulation system facilitates a bidirectional control of gene expression.The gene of interest can be precisely controlled by dual small molecules in a broad dynamic range of expression from overexpression to complete silence,allowing gene function study in a comprehensive expression profile.Our results reveal that the bidirectional control system enables sensitive dosage-and time-dependent regulation for either turn-on or shutoff of gene expression.We also apply this system for inducible genome editing and gene activation mediated by clustered regularly interspaced short palindromic repeats.The system provides an integrated platform for studying multiple biological processes by manipulating gene expression in a more flexible way.
