Maize(Zea mays L.)is a monoecious grass plant in which mature male and female florets form the tassel and ear,respectively.Maize is often used as a model plant to study flower development.Several maize tassel seed mut...Maize(Zea mays L.)is a monoecious grass plant in which mature male and female florets form the tassel and ear,respectively.Maize is often used as a model plant to study flower development.Several maize tassel seed mutants,such as the recessive mutants tasselseed1(ts1)and tasselseed2(ts2),exhibit a reversal in sex determination,which leads to the generation of seeds in tassels.The phenotype of the dominant mutant,Tasselseed5(Ts5),is similar to that of ts2.Here,we positionally cloned the underlying gene of Ts5 and characterized its function.We show that the GRMZM2G177668 gene is overexpressed in Ts5.This gene encodes a cytochrome C oxidase,which catalyzes the transformation of jasmonoyl-L-isoleucine(JA-Ile)to 12 OH-JA-Ile during jasmonic acid catabolism.Consistent with this finding,no JA-Ile peak was detected in Ts5 tassels during the sex determination period,unlike in the wild type.Transgenic maize plants overexpressing GRMZM2G177668 exhibited a tassel-seed phenotype similar to that of Ts5.These results indicate that the JA-Ile peak in tassels is critical for sex determination and that the Ts5 mutant phenotype results from the disruption of this peak in tassels during sex determination.展开更多
Amyotrophic lateral sclerosis(ALS)is the most common motor neuron disease.At present,no definite ALS biomarkers are available.In this study,exosomes from the plasma of patients with ALS and healthy controls were extra...Amyotrophic lateral sclerosis(ALS)is the most common motor neuron disease.At present,no definite ALS biomarkers are available.In this study,exosomes from the plasma of patients with ALS and healthy controls were extracted,and differentially expressed exosomal proteins were compared.Among them,the expression of exosomal coronin-1a(CORO1A)was 5.3-fold higher than that in the controls.CORO1A increased with disease progression at a certain proportion in the plasma of patients with ALS and in the spinal cord of ALS mice.CORO1A was also overexpressed in NSC-34 motor neuron-like cells,and apoptosis,oxidative stress,and autophagic protein expression were evaluated.CORO1A overexpression resulted in increased apoptosis and oxidative stress,overactivated autophagy,and hindered the formation of autolysosomes.Moreover,CORO1A activated Ca^(2+)-dependent phosphatase calcineurin,thereby blocking the fusion of autophagosomes and lysosomes.The inhibition of calcineurin activation by cyclosporin A reversed the damaged autolysosomes.In conclusion,the role of CORO1A in ALS pathogenesis was discovered,potentially affecting the disease onset and progression by blocking autophagic flux.Therefore,CORO1A might be a potential biomarker and therapeutic target for ALS.展开更多
基金supported by the National Transgenic Science and Technology Program(2016ZX08010-002)the National Key Research and Development Program of China(2016YFD0100602)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA08010201-1).
文摘Maize(Zea mays L.)is a monoecious grass plant in which mature male and female florets form the tassel and ear,respectively.Maize is often used as a model plant to study flower development.Several maize tassel seed mutants,such as the recessive mutants tasselseed1(ts1)and tasselseed2(ts2),exhibit a reversal in sex determination,which leads to the generation of seeds in tassels.The phenotype of the dominant mutant,Tasselseed5(Ts5),is similar to that of ts2.Here,we positionally cloned the underlying gene of Ts5 and characterized its function.We show that the GRMZM2G177668 gene is overexpressed in Ts5.This gene encodes a cytochrome C oxidase,which catalyzes the transformation of jasmonoyl-L-isoleucine(JA-Ile)to 12 OH-JA-Ile during jasmonic acid catabolism.Consistent with this finding,no JA-Ile peak was detected in Ts5 tassels during the sex determination period,unlike in the wild type.Transgenic maize plants overexpressing GRMZM2G177668 exhibited a tassel-seed phenotype similar to that of Ts5.These results indicate that the JA-Ile peak in tassels is critical for sex determination and that the Ts5 mutant phenotype results from the disruption of this peak in tassels during sex determination.
基金This work was supported by the Clinical Research Plan of SHDC(No.SHDC2020CR2027B)。
文摘Amyotrophic lateral sclerosis(ALS)is the most common motor neuron disease.At present,no definite ALS biomarkers are available.In this study,exosomes from the plasma of patients with ALS and healthy controls were extracted,and differentially expressed exosomal proteins were compared.Among them,the expression of exosomal coronin-1a(CORO1A)was 5.3-fold higher than that in the controls.CORO1A increased with disease progression at a certain proportion in the plasma of patients with ALS and in the spinal cord of ALS mice.CORO1A was also overexpressed in NSC-34 motor neuron-like cells,and apoptosis,oxidative stress,and autophagic protein expression were evaluated.CORO1A overexpression resulted in increased apoptosis and oxidative stress,overactivated autophagy,and hindered the formation of autolysosomes.Moreover,CORO1A activated Ca^(2+)-dependent phosphatase calcineurin,thereby blocking the fusion of autophagosomes and lysosomes.The inhibition of calcineurin activation by cyclosporin A reversed the damaged autolysosomes.In conclusion,the role of CORO1A in ALS pathogenesis was discovered,potentially affecting the disease onset and progression by blocking autophagic flux.Therefore,CORO1A might be a potential biomarker and therapeutic target for ALS.
