Mammalian Bax-induced plant cell death can be down-regulated by overexpression of Arabidopsis Bax Inhibitor-1 (AtBI-1).
We recently isolated the AtBI-1 (Arabidopsis Bax Inhibitor-1) gene, the expression of which suppressed Bax-induced cell death in yeast. To determine whether the same is true in the plant system, transgenic Arabidopsis plants overexpressing Bax protein under a dexamethasone (DEX)-inducible promoter were generated. On DEX treatment, such transgenic plants exhibited marked cell death at the whole-plant level, cell shrinkage, membranous destruction, and other apoptotic phenotypes. Transgenic Bax plants were retransformed with a vector containing the AtBI-1 gene (tagged with green fluorescent protein) under the control of the cauliflower mosaic virus 35S promoter. Plants expressing both Bax and AtBI-1 were able to maintain growth on DEX-treatment by sustaining intracellular integrity. Thus, we present here direct genetic evidence that the plant antiapoptotic protein AtBI-1 is biologically active in suppressing the mammalian Bax action in planta.
Kawai-Yamada
M
M
Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
Jin
L
L
Yoshinaga
K
K
Hirata
A
A
Uchimiya
H
H
D000818:Animals; D017209:Apoptosis; D017360:Arabidopsis; D029681:Arabidopsis Proteins; D015536:Down-Regulation; D015870:Gene Expression; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008322:Mammals; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D014026:Nicotiana; D051028:bcl-2-Associated X Protein
C491862:ATBI-1 protein, Arabidopsis; D029681:Arabidopsis Proteins; C494827:Bax protein, mouse; D008164:Luminescent Proteins; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D049452:Green Fluorescent Proteins