[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines o...[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [ Result] The segregation ratio is consistent with mendelian law（3：1）. The mutant assumed not only higher plant height, wider straw and earlier florescence, but also more tillers, bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene（Bar） in the T-DNA inserted, proving that the mutant is not caused by the insertion of T-DNA containing target gene （Bar）. [ Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.展开更多
A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell cultu...A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic （H1N1） viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology （96%-99%） with known epidemic strains （A/Califomia/04/2009（H1N1）. Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 （221-228） of the HA receptor binding site in the 39 HA sequences： A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.展开更多
Rice blast caused by Magnaporthe oryzae （M. oryzae） is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among...Rice blast caused by Magnaporthe oryzae （M. oryzae） is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among different isolates of M. oryzae in nature, we re-sequenced the genomes of two field isolates, CH43 and Zhong-10-8-14, which showed distinct pathogenecity on most of the rice cultivars. Genome-wide genetic variation analysis reveals that ZHONG-10-8-14 exhibits higher sequence variations than CH43. Structural variations （SVs） detection shows that the sequence variations primarily occur in exons and intergenic regions. Bioinformatics analysis for gene variations reveals that many pathogenecity-related pathways are enriched. In addition, 193 candidate effectors with various DNA polymorphisms were identified, including two known effectors AVR-Pik and AVR-Pital. Comparative polymorphism analysis of thirteen randomly selected effectors suggests that the genetic variations of effectors are under positive selection. The expression pattern analysis of several pathogenecity-related variant genes indicates that these genes are differentially regulated in two isolates, with much higher expression levels in Zhong-10-8-14 than CH43. Our data demonstrate that the genetic variations of effectors and pathogenecity-related genes are under positive selection, resulting in the distinct pathogeuicities of CH43 and Zhong- 10-8-14 on rice.展开更多
文摘[ Objective ] The study aimed to reveal the genetic model of a biomass mutant in Oryza sativa. [ Method ] In the process of screening and identification of Bar-transgenic rice, a biomass mutant was found in 10 lines of T1 progenies. The mutant was investigated for genetic analysis and agronomic traits by herbicide spraying and PCR amplification. [ Result] The segregation ratio is consistent with mendelian law（3：1）. The mutant assumed not only higher plant height, wider straw and earlier florescence, but also more tillers, bigger spikes and resultantly higher biomass. PCR detections indicated that no co-segregation was observed between mutant traits and target gene（Bar） in the T-DNA inserted, proving that the mutant is not caused by the insertion of T-DNA containing target gene （Bar）. [ Conclusion] Our study may avail to understand the cloning of mutant gene and the mechanism of the mutant gene on biomass.
基金The Ministry of Science and Technology of China (2010CB534005,2007FY210700, 2009ZX10004109)the National Natural Science Foundation of China (30970024,30900060)+2 种基金The National R&D Infrastructure and Facility Development Program of China under Grant No. BSDN2009-10 &18The Chinese Academy of Sciences (KSCX2-YW- N-065, KSCX2-YW-R-157, 158 and 159 INFO-115-C01-SDB3-01, INFO-115-C01-SDB4-21, IN-FO-115-D02, IN-FO- 115-C01-SDB2-02)
文摘A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic （H1N1） viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology （96%-99%） with known epidemic strains （A/Califomia/04/2009（H1N1）. Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 （221-228） of the HA receptor binding site in the 39 HA sequences： A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.
基金supported by the Chinese Academy of Sciences(Strategic Priority Research Program XDB11020300)National Natural Science Foundation of China(31570252,31601629)+1 种基金the start-up fund of"One Hundred Talents"program of the Chinese Academy of Sciences and by the grants from the State Key Laboratory of Plant Genomics(O8KF021011)the Key Laboratory of Urban Agriculture(North)of Ministry of Agriculture of China Beijing University of Agriculture(KFK2015001)
文摘Rice blast caused by Magnaporthe oryzae （M. oryzae） is one of the most destructive diseases, which causes significant rice yield losses and affects global food security. To better understand genetic variations among different isolates of M. oryzae in nature, we re-sequenced the genomes of two field isolates, CH43 and Zhong-10-8-14, which showed distinct pathogenecity on most of the rice cultivars. Genome-wide genetic variation analysis reveals that ZHONG-10-8-14 exhibits higher sequence variations than CH43. Structural variations （SVs） detection shows that the sequence variations primarily occur in exons and intergenic regions. Bioinformatics analysis for gene variations reveals that many pathogenecity-related pathways are enriched. In addition, 193 candidate effectors with various DNA polymorphisms were identified, including two known effectors AVR-Pik and AVR-Pital. Comparative polymorphism analysis of thirteen randomly selected effectors suggests that the genetic variations of effectors are under positive selection. The expression pattern analysis of several pathogenecity-related variant genes indicates that these genes are differentially regulated in two isolates, with much higher expression levels in Zhong-10-8-14 than CH43. Our data demonstrate that the genetic variations of effectors and pathogenecity-related genes are under positive selection, resulting in the distinct pathogeuicities of CH43 and Zhong- 10-8-14 on rice.
