Agrobacterium transfers single-stranded T-DNA(T-strands)and virulence effector proteins into plant cells.VirE2,a key effector protein,enters the plant cell and is thought to bind T-strands,protecting them from nucleas...Agrobacterium transfers single-stranded T-DNA(T-strands)and virulence effector proteins into plant cells.VirE2,a key effector protein,enters the plant cell and is thought to bind T-strands,protecting them from nuclease degradation and guiding them to the nucleus.However,the intracellular trafficking mechanisms of VirE2 remain unclear.Using bimolecular fluorescence complementation,in vitro pull-down,yeast twohybrid,and in vivo co-immunoprecipitation assays,we found that VirE2 binds directly to the cargo-binding domains(CBDs)of several myosin VIII family members and to myosin XI-K.We observed reduced susceptibility to Agrobacterium-mediated transformation of several Arabidopsis actin mutants and in a myosin VIII-1/2/a/b quadruple mutant.Expression of the CBDs of myosin VIII-1,VIII-2,VIII-A,or VIII-B in transgenic plants will inhibit Arabidopsis root transformation.However,none of the myosin VIII proteins contributes to the intracellular trafficking of VirE2.Expression of myosin VIII-2,VIII-A,and VIII-B,but not VIII-1,cDNAs in the myosin VIII-1/2/a/b mutant can partially restore transformation efficiency.Furthermore,functional fluorescent protein-tagged VirE2 synthesized in plant cells relocalizes from the cell periphery to the cytoplasm following T-strand delivery from Agrobacterium.Surprisingly,an Arabidopsis myosin XI-k mutant,transgenic plants expressing the myosin XI-K CBD,and plants subjected to RNAi targeting myosin XI-k all remain highly transformable,even though VirE2 movement along actin filaments is blocked.We hypothesize that myosin VIII proteins facilitate VirE2 tethering to the plasma membrane and are required for its efficient localization to membrane sites where it binds incoming T-strands,whereas myosin XI-K is important for VirE2 movement through the cytoplasm toward the nucleus.展开更多
Using linear interpolation method, VIRE algorithm simply treats the signal strength value and distance of the reference tag as a linear relationship, leading to the inaccuracy of signal strength value for virtual refe...Using linear interpolation method, VIRE algorithm simply treats the signal strength value and distance of the reference tag as a linear relationship, leading to the inaccuracy of signal strength value for virtual reference tags. The threshold in VIRE algorithm is a fixed value that needs repeatedly adjustment through experiments, which results in the complicated algorithm. To solve these problems, an improved algorithm is proposed in this paper, including nonlinear interpolation algorithm, dynamic threshold setting and tag self-correction of fuzzy map, which builds an indoor positioning system based on reference tags. The experimental results show that the improved algorithm can improve the positioning accuracy and improve the stability of positioning results under bad environmental conditions without increasing the number of reference tags.展开更多
基金supported by grants from the U.S.National Science Foundation(IOS-1725122 and IOS-2006668)P.Y.was supported by a SERB-Purdue University Overseas Visiting Doctoral Fellowship.DNA sequence data were obtained with partial support from NIH P30 grant CA023168 to the Purdue University Cancer Center.
文摘Agrobacterium transfers single-stranded T-DNA(T-strands)and virulence effector proteins into plant cells.VirE2,a key effector protein,enters the plant cell and is thought to bind T-strands,protecting them from nuclease degradation and guiding them to the nucleus.However,the intracellular trafficking mechanisms of VirE2 remain unclear.Using bimolecular fluorescence complementation,in vitro pull-down,yeast twohybrid,and in vivo co-immunoprecipitation assays,we found that VirE2 binds directly to the cargo-binding domains(CBDs)of several myosin VIII family members and to myosin XI-K.We observed reduced susceptibility to Agrobacterium-mediated transformation of several Arabidopsis actin mutants and in a myosin VIII-1/2/a/b quadruple mutant.Expression of the CBDs of myosin VIII-1,VIII-2,VIII-A,or VIII-B in transgenic plants will inhibit Arabidopsis root transformation.However,none of the myosin VIII proteins contributes to the intracellular trafficking of VirE2.Expression of myosin VIII-2,VIII-A,and VIII-B,but not VIII-1,cDNAs in the myosin VIII-1/2/a/b mutant can partially restore transformation efficiency.Furthermore,functional fluorescent protein-tagged VirE2 synthesized in plant cells relocalizes from the cell periphery to the cytoplasm following T-strand delivery from Agrobacterium.Surprisingly,an Arabidopsis myosin XI-k mutant,transgenic plants expressing the myosin XI-K CBD,and plants subjected to RNAi targeting myosin XI-k all remain highly transformable,even though VirE2 movement along actin filaments is blocked.We hypothesize that myosin VIII proteins facilitate VirE2 tethering to the plasma membrane and are required for its efficient localization to membrane sites where it binds incoming T-strands,whereas myosin XI-K is important for VirE2 movement through the cytoplasm toward the nucleus.
文摘Using linear interpolation method, VIRE algorithm simply treats the signal strength value and distance of the reference tag as a linear relationship, leading to the inaccuracy of signal strength value for virtual reference tags. The threshold in VIRE algorithm is a fixed value that needs repeatedly adjustment through experiments, which results in the complicated algorithm. To solve these problems, an improved algorithm is proposed in this paper, including nonlinear interpolation algorithm, dynamic threshold setting and tag self-correction of fuzzy map, which builds an indoor positioning system based on reference tags. The experimental results show that the improved algorithm can improve the positioning accuracy and improve the stability of positioning results under bad environmental conditions without increasing the number of reference tags.
