Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolati...Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolating and identifying mutants with altered apical dominance. Here we report isolation of a bushy and dwarf 1 (bud1) mutant from Arabidopsis thaliana L. through a T-DNA tagging approach. The phenotypes of bul1 plants include loss of apical dominance, reduced plant size and dwarfism, suggesting that the bud1 mutant may be involved in auxin metabolism, transport or signalling. Using a reporter gene driven by an auxin-responsive promoter, we found that the expression pattern of auxin response element was altered in bud1. The auxin sensitivity and transport assay indicates that these two processes are normal in bud1. These results suggest that the bud1 phenotypes may result from an alteration in auxin metabolism. Genetic analysis demonstrates that bud1 is a semidominant mutant and cosegregates with a T-DNA insertion, which indicates that BUD1 gene could be cloned by iPCR approach.展开更多
Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum （Sorghum bicolor）. Here, we identified and functionally characterized a mutant of the Non- dor...Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum （Sorghum bicolor）. Here, we identified and functionally characterized a mutant of the Non- dormant Axillary Bud 1 （NAB1） gene from an ethyl methanesulfonate-mutagenized sorghum population. The nab1 mutants have increased tillering and reduced plant height. Map-based cloning revealed that NAB~ encodes a carotenoid-cleavage dioxygenase 7 （CCDT） orthologous to rice COryza sativa） HIGH-TILLERING DWARF1/ DWARF^7 and Arabidopsis thaliana MORE AXILLARY BRANCHING 3. NAB1 is primarily expressed in axillary nodes and tiller bases and NAB1 localizes to chloroplasts. The nab1 mutation causes outgrowth of basal axillary buds; removing these non-dormant basal axillary buds restoredthe wild-type phenotype. The tillering of nab1 plants was completely suppressed by exogenous application of the synthetic strigolactone analog GR24. Moreover, the nab1 plants had no detectable strigolactones and displayed stronger polar auxin transport than wild-type plants. Finally, RNA-seq showed that the expression of genes involved in multiple processes, including auxin-related genes, was significantly altered in nab1. These results suggest that NAB1 functions in strigolactone biosynthesis and the regulation of shoot branching via an interaction with auxin transport.展开更多
Hepatocyte growth factor-regulated tyrosine kinase substrate(Hrs)is a key component of the endosomal sorting complexes required for transport and has been demonstrated to play a regulatory role in endocytosis/exocytos...Hepatocyte growth factor-regulated tyrosine kinase substrate(Hrs)is a key component of the endosomal sorting complexes required for transport and has been demonstrated to play a regulatory role in endocytosis/exocytosis and the accumulation of internal vesicles in multivesicular bodies.Citron kinase is a Ser/The kinase that we previously reported to enhance human immunodeficiency virus type 1(HIV-1)virion production.However,the relationship between Hrs and citron kinase in HIV-1 production remains elusive.Here,we report that Hrs interacts with citron kinase via its FYVE domain.Overexpression of Hrs or the FYVE domain resulted in a significant decrease in HIV-1 virion production.Depletion of Hrs by RNA interference in HEK293T cells increased HIV-1 virion production and enhanced the activity of citron kinase.These data suggest that Hrs inhibits HIV-1 production by inhibiting citron kinase-mediated exocytosis.展开更多
文摘Apical dominance is a phenomenon that the growth of axillary meristems is inhibited by the primary shoot or inflorescence. Recent researches have begun to reveal the molecular mechanisms of apical dominance by isolating and identifying mutants with altered apical dominance. Here we report isolation of a bushy and dwarf 1 (bud1) mutant from Arabidopsis thaliana L. through a T-DNA tagging approach. The phenotypes of bul1 plants include loss of apical dominance, reduced plant size and dwarfism, suggesting that the bud1 mutant may be involved in auxin metabolism, transport or signalling. Using a reporter gene driven by an auxin-responsive promoter, we found that the expression pattern of auxin response element was altered in bud1. The auxin sensitivity and transport assay indicates that these two processes are normal in bud1. These results suggest that the bud1 phenotypes may result from an alteration in auxin metabolism. Genetic analysis demonstrates that bud1 is a semidominant mutant and cosegregates with a T-DNA insertion, which indicates that BUD1 gene could be cloned by iPCR approach.
基金funded by grants from the National Natural Science Foundation of China(31461143023 and 31471570)the Ministry of Science and Technology of the People’s Republic of China(2015BAD15B03)to Hai-Chun Jing
文摘Tillering contributes to grain yield and plant architecture and therefore is an agronomically important trait in sorghum （Sorghum bicolor）. Here, we identified and functionally characterized a mutant of the Non- dormant Axillary Bud 1 （NAB1） gene from an ethyl methanesulfonate-mutagenized sorghum population. The nab1 mutants have increased tillering and reduced plant height. Map-based cloning revealed that NAB~ encodes a carotenoid-cleavage dioxygenase 7 （CCDT） orthologous to rice COryza sativa） HIGH-TILLERING DWARF1/ DWARF^7 and Arabidopsis thaliana MORE AXILLARY BRANCHING 3. NAB1 is primarily expressed in axillary nodes and tiller bases and NAB1 localizes to chloroplasts. The nab1 mutation causes outgrowth of basal axillary buds; removing these non-dormant basal axillary buds restoredthe wild-type phenotype. The tillering of nab1 plants was completely suppressed by exogenous application of the synthetic strigolactone analog GR24. Moreover, the nab1 plants had no detectable strigolactones and displayed stronger polar auxin transport than wild-type plants. Finally, RNA-seq showed that the expression of genes involved in multiple processes, including auxin-related genes, was significantly altered in nab1. These results suggest that NAB1 functions in strigolactone biosynthesis and the regulation of shoot branching via an interaction with auxin transport.
基金in part supported by grants to Guangxia Gao from the National Natural Science Foundation of China(Grant No.81030030)the Ministry of Science and Technology of China(No.2009zx09501-029).
文摘Hepatocyte growth factor-regulated tyrosine kinase substrate(Hrs)is a key component of the endosomal sorting complexes required for transport and has been demonstrated to play a regulatory role in endocytosis/exocytosis and the accumulation of internal vesicles in multivesicular bodies.Citron kinase is a Ser/The kinase that we previously reported to enhance human immunodeficiency virus type 1(HIV-1)virion production.However,the relationship between Hrs and citron kinase in HIV-1 production remains elusive.Here,we report that Hrs interacts with citron kinase via its FYVE domain.Overexpression of Hrs or the FYVE domain resulted in a significant decrease in HIV-1 virion production.Depletion of Hrs by RNA interference in HEK293T cells increased HIV-1 virion production and enhanced the activity of citron kinase.These data suggest that Hrs inhibits HIV-1 production by inhibiting citron kinase-mediated exocytosis.
