Magnaporthe oryzae is known for its genetic diversity and pathogenic variability,leading to rapid breakdown of resistance in rice.Incorporating multiple broad-spectrum blast resistance genes into rice cultivars would ...Magnaporthe oryzae is known for its genetic diversity and pathogenic variability,leading to rapid breakdown of resistance in rice.Incorporating multiple broad-spectrum blast resistance genes into rice cultivars would extend disease resistance longevity.Effective resistance breeding in rice therefore requires continual enrichment of the reservoir of resistance genes and alleles.We conducted a large-scale screen of rice blast resistance in about 2000 rice accessions.Among them,247 accessions showed at least medium resistance to the natural infection of rice blast and 7 novel Pik alleles were identified from them.Variations in gene sequences were then correlated with the phenotypic trait to enable the identification of favorable alleles.Among the seven novel Pik alleles,the resistant rate of Pik-R0/ME/7017 donors was greater than 80%,and the disease score was less than 3.Through molecular marker-assisted backcross breeding,we successfully transferred the three Pik alleles,Pik-R0/ME/7017,into an elite cultivated line Kongyu 131 to obtain BC_(3)F_(2)lines,which showed enhanced resistance to rice blast compared with the recurrent parent.Assessment of these near-isogenic lines in the greenhouse using 31 isolates of M.oryzae from Heilongjiang Province of China revealed that the resistant levels of the BC_(3)F_(2)lines with Pik-R0/ME/7017 were significantly higher than those of the established cloned resistance genes Pik-m and Pi1.Exploring such alleles will enrich our gene library for resistance to rice blast.展开更多
AIM To evaluate PIK3 CA gene mutational status in Northwest Chinese esophageal squamous cell carcinoma(ESCC) patients, and examine the associations of PIK3 CA gene mutations with clinicopathological characteristics an...AIM To evaluate PIK3 CA gene mutational status in Northwest Chinese esophageal squamous cell carcinoma(ESCC) patients, and examine the associations of PIK3 CA gene mutations with clinicopathological characteristics and clinical outcome.METHODS A total of 210 patients with ESCC who underwent curative resection were enrolled in this study. Pyrosequencing was applied to investigate mutations in exons 9 and 20 of PIK3 CA gene in 210 Northwest Chinese ESCCs. The associations of PIK3 CA gene mutations with clinicopathological characteristics and clinical outcome were examined.RESULTS PIK3 CA gene mutations in exon 9 were detected in 48 cases(22.9%) of a non-biased database of 210 curatively resected Northwest Chinese ESCCs. PIK3 CA gene mutations were not associated with sex, tobacco use, alcohol use, tumor location, stage, or local recurrence. When compared with wild-type PIK3 CA gene cases, patients with PIK3 CA gene mutations in exons 9 experienced significantly better disease-free survival and overall survival rates.CONCLUSION The results of this study suggest that PIK3 CA gene mutations could act as a prognostic biomarker in Northwest Chinese ESCC patients.展开更多
基金This study was supported by the National Natural Science Foundation of China(Grant No.62176192)Key Laboratory of Integrated Management of Crops of Central China and Hubei Key Laboratory of Crop Disease,Insect Pests and Weeds Control(Grant No.2019ZTSJJ2)China Scholarship Council(CSC No.201908420374).
文摘Magnaporthe oryzae is known for its genetic diversity and pathogenic variability,leading to rapid breakdown of resistance in rice.Incorporating multiple broad-spectrum blast resistance genes into rice cultivars would extend disease resistance longevity.Effective resistance breeding in rice therefore requires continual enrichment of the reservoir of resistance genes and alleles.We conducted a large-scale screen of rice blast resistance in about 2000 rice accessions.Among them,247 accessions showed at least medium resistance to the natural infection of rice blast and 7 novel Pik alleles were identified from them.Variations in gene sequences were then correlated with the phenotypic trait to enable the identification of favorable alleles.Among the seven novel Pik alleles,the resistant rate of Pik-R0/ME/7017 donors was greater than 80%,and the disease score was less than 3.Through molecular marker-assisted backcross breeding,we successfully transferred the three Pik alleles,Pik-R0/ME/7017,into an elite cultivated line Kongyu 131 to obtain BC_(3)F_(2)lines,which showed enhanced resistance to rice blast compared with the recurrent parent.Assessment of these near-isogenic lines in the greenhouse using 31 isolates of M.oryzae from Heilongjiang Province of China revealed that the resistant levels of the BC_(3)F_(2)lines with Pik-R0/ME/7017 were significantly higher than those of the established cloned resistance genes Pik-m and Pi1.Exploring such alleles will enrich our gene library for resistance to rice blast.
基金Supported by National Natural Science Foundation of China,No.81602023
文摘AIM To evaluate PIK3 CA gene mutational status in Northwest Chinese esophageal squamous cell carcinoma(ESCC) patients, and examine the associations of PIK3 CA gene mutations with clinicopathological characteristics and clinical outcome.METHODS A total of 210 patients with ESCC who underwent curative resection were enrolled in this study. Pyrosequencing was applied to investigate mutations in exons 9 and 20 of PIK3 CA gene in 210 Northwest Chinese ESCCs. The associations of PIK3 CA gene mutations with clinicopathological characteristics and clinical outcome were examined.RESULTS PIK3 CA gene mutations in exon 9 were detected in 48 cases(22.9%) of a non-biased database of 210 curatively resected Northwest Chinese ESCCs. PIK3 CA gene mutations were not associated with sex, tobacco use, alcohol use, tumor location, stage, or local recurrence. When compared with wild-type PIK3 CA gene cases, patients with PIK3 CA gene mutations in exons 9 experienced significantly better disease-free survival and overall survival rates.CONCLUSION The results of this study suggest that PIK3 CA gene mutations could act as a prognostic biomarker in Northwest Chinese ESCC patients.
