Penaeidin from Chinese shrimp (Fenneropenaeus chinensis) has proved to be one of the most important antimicrobial peptides in the bodies of animals. The relative quantitative real-time PCR method is developed to study...Penaeidin from Chinese shrimp (Fenneropenaeus chinensis) has proved to be one of the most important antimicrobial peptides in the bodies of animals. The relative quantitative real-time PCR method is developed to study through time, the mRNA expression profile of penaeidin in the muscle and haemocyte tissue of Chinese shrimp infected with vibrio (Vibrio anguillarum) and WSSV (white spot syndrome virus). Research results showed that the same pathogens infection experiments produced similar gene expression profile in different tissues while different expression profiles appeared in the same tissues infected by different exterior pathogens. In vibrio infection experiments, a 'U' like expression profile resulted. Expression levels of penaeidin increased and surpassed the non-stimulated level, indicating that penaeidin from Chinese shrimp has noticeable antimicrobial activities. In WSSV infection experiments, the expression profile appeared as an inverse 'U' with the expression of penaeidin gradually decreasing to below baseline level after 24 h. The expression of antimicrobial peptides gene in mRNA level in response to virus infection in shrimp showed that international mechanisms of virus to haemocytes and microbial to haemocytes are completely different. Decline of penaeidins expression levels may be due to haemocytes being destroyed by WSSV or that the virus can inhibit the expression of penaeidins by yet undiscovered modes. The expression profiles of penaeidin in response to exterior pathogen and the difference of expression profiles between vibrio and WSSV infection provided some clues to further understanding the complex innate immune mechanism in shrimp.展开更多
Penaeidin-2（Pen-2） is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant p...Penaeidin-2（Pen-2） is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant penaeidins show similar activities to the native Pen-2 protein. Previous researches have shown that some antimicrobial peptides（AMPs） exhibit cytotoxic activity against cancer cells. To date, there have been no studies on the antitumor effects of Pen-2. This study evaluated the potential of recombinant pen-2（rPen-2） in the selective killing of kidney cancer cell lines ACHN and A498, and its action mechanism. MTT assays found the maximal growth inhibition of HK-2, ACHN and A498 cells treated with 100 μg/mL rPen-2 at 48 h was 13.2%, 62.4%, and 70.4%, respectively. DNA-specific fluorescent dye staining showed a high percentage of apoptosis on cancer cells. Flow cytometry revealed that the apoptosis rate of HK-2, ACHN and A498 cells was 15.2%, 55.2%, and 61.5% at 48 h respectively, suggesting that rPen-2 induced higher apoptosis rate in cancer cells than in HK-2 cells. Laser confocal scanning microscopy demonstrated that the plasma membrane was the key site where rPen-2 interacted with and destroyed tumor cells. Scanning electron microscopy showed the morphologic changes of the cell membranes of kidney cancer cells treated with rPen-2. These results suggest that rPen-2 is a novel potential therapeutic agent that may be useful in treating kidney cancers.展开更多
Vibrio parahaemolyticus carrying a plasmid encoding the PirAvp and PirBvp toxins is the causative agent of acute hepatopancreatic necrosis disease(AHPND)in penaeid shrimps.In the Pacific white shrimp farming industry,...Vibrio parahaemolyticus carrying a plasmid encoding the PirAvp and PirBvp toxins is the causative agent of acute hepatopancreatic necrosis disease(AHPND)in penaeid shrimps.In the Pacific white shrimp farming industry,one possible strategy to reduce economic loss due to AHPND is the development of a shrimp line resistant to the disease.In this study,we identified single nucleotide polymorphisms(SNPs)in the Litopenaeus vannamei anti-lipopolysaccharide factor 1(nLvALF1)and penaeidin 2-1(PEN2-1)genes,and we analyzed the associations between these SNPs and resistance/susceptibility to V.parahaemolyticus infection in the Pacific white shrimp.Postlarvae(PL20)shrimp from a local hatchery in Prachuap Khiri Khan Province were challenged with an isolate of VPAHPND and mortality was observed for 14 days.DNA was extracted from susceptible(died within 6 days)and resistant(survived the challenge)shrimp(45 individuals/group)and used for PCR amplifications of nLvALF1(397 bp)and PEN2-1(637 bp)gene fragments.PCR products were sequenced by direct sequencing and SNPs were identified from sequencing chromatograms.Nine and seven SNPs were identified in nLvALF1 and PEN2-1 gene fragments,respectively.Analyses of allele frequencies in susceptible and resistant samples using Chi-square tests revealed that four and six SNPs in nLvALF1 and PEN2-1,respectively,were associated with resistance/susceptibility to V.parahaemolyticus infection(P<0.05).The SNPs in the candidate genes identified here are potential DNA markers for breeding V.parahaemolyticus-resistant Pacific white shrimp in the study population;however,further validation will be required if these SNPs are to be used across populations.展开更多
文摘Penaeidin from Chinese shrimp (Fenneropenaeus chinensis) has proved to be one of the most important antimicrobial peptides in the bodies of animals. The relative quantitative real-time PCR method is developed to study through time, the mRNA expression profile of penaeidin in the muscle and haemocyte tissue of Chinese shrimp infected with vibrio (Vibrio anguillarum) and WSSV (white spot syndrome virus). Research results showed that the same pathogens infection experiments produced similar gene expression profile in different tissues while different expression profiles appeared in the same tissues infected by different exterior pathogens. In vibrio infection experiments, a 'U' like expression profile resulted. Expression levels of penaeidin increased and surpassed the non-stimulated level, indicating that penaeidin from Chinese shrimp has noticeable antimicrobial activities. In WSSV infection experiments, the expression profile appeared as an inverse 'U' with the expression of penaeidin gradually decreasing to below baseline level after 24 h. The expression of antimicrobial peptides gene in mRNA level in response to virus infection in shrimp showed that international mechanisms of virus to haemocytes and microbial to haemocytes are completely different. Decline of penaeidins expression levels may be due to haemocytes being destroyed by WSSV or that the virus can inhibit the expression of penaeidins by yet undiscovered modes. The expression profiles of penaeidin in response to exterior pathogen and the difference of expression profiles between vibrio and WSSV infection provided some clues to further understanding the complex innate immune mechanism in shrimp.
文摘Penaeidin-2（Pen-2） is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant penaeidins show similar activities to the native Pen-2 protein. Previous researches have shown that some antimicrobial peptides（AMPs） exhibit cytotoxic activity against cancer cells. To date, there have been no studies on the antitumor effects of Pen-2. This study evaluated the potential of recombinant pen-2（rPen-2） in the selective killing of kidney cancer cell lines ACHN and A498, and its action mechanism. MTT assays found the maximal growth inhibition of HK-2, ACHN and A498 cells treated with 100 μg/mL rPen-2 at 48 h was 13.2%, 62.4%, and 70.4%, respectively. DNA-specific fluorescent dye staining showed a high percentage of apoptosis on cancer cells. Flow cytometry revealed that the apoptosis rate of HK-2, ACHN and A498 cells was 15.2%, 55.2%, and 61.5% at 48 h respectively, suggesting that rPen-2 induced higher apoptosis rate in cancer cells than in HK-2 cells. Laser confocal scanning microscopy demonstrated that the plasma membrane was the key site where rPen-2 interacted with and destroyed tumor cells. Scanning electron microscopy showed the morphologic changes of the cell membranes of kidney cancer cells treated with rPen-2. These results suggest that rPen-2 is a novel potential therapeutic agent that may be useful in treating kidney cancers.
基金Funding for this research was provided by the National Science and Technology Development Agency,Ministry of Higher Education,Science,Research and Innovation.
文摘Vibrio parahaemolyticus carrying a plasmid encoding the PirAvp and PirBvp toxins is the causative agent of acute hepatopancreatic necrosis disease(AHPND)in penaeid shrimps.In the Pacific white shrimp farming industry,one possible strategy to reduce economic loss due to AHPND is the development of a shrimp line resistant to the disease.In this study,we identified single nucleotide polymorphisms(SNPs)in the Litopenaeus vannamei anti-lipopolysaccharide factor 1(nLvALF1)and penaeidin 2-1(PEN2-1)genes,and we analyzed the associations between these SNPs and resistance/susceptibility to V.parahaemolyticus infection in the Pacific white shrimp.Postlarvae(PL20)shrimp from a local hatchery in Prachuap Khiri Khan Province were challenged with an isolate of VPAHPND and mortality was observed for 14 days.DNA was extracted from susceptible(died within 6 days)and resistant(survived the challenge)shrimp(45 individuals/group)and used for PCR amplifications of nLvALF1(397 bp)and PEN2-1(637 bp)gene fragments.PCR products were sequenced by direct sequencing and SNPs were identified from sequencing chromatograms.Nine and seven SNPs were identified in nLvALF1 and PEN2-1 gene fragments,respectively.Analyses of allele frequencies in susceptible and resistant samples using Chi-square tests revealed that four and six SNPs in nLvALF1 and PEN2-1,respectively,were associated with resistance/susceptibility to V.parahaemolyticus infection(P<0.05).The SNPs in the candidate genes identified here are potential DNA markers for breeding V.parahaemolyticus-resistant Pacific white shrimp in the study population;however,further validation will be required if these SNPs are to be used across populations.
