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ARA7(Q69L) expression in transgenic Arabidopsis cells induces the formation of enlarged multivesicular bodies.

ABSTRACT: Arabidopsis thaliana ARA7 (AtRabF2b), a member of the plant Rab5 small GTPases functioning in the vacuolar transport pathway, localizes to pre-vacuolar compartments (PVCs), known as multivesicular bodies (MVBs) in plant cells. Overexpression of the constitutively active GTP-bound mutant of ARA7, ARA7(Q69L), induces the formation of large ring-like structures (1-2 µm in diameter). To better understand the biology of these ARA7(Q69L)-induced ring-like structures, transgenic Arabidopsis cell lines expressing ARA7(Q69L) tagged with green fluorescent protein (GFP) under the control of a heat shock-inducible promoter were generated. In these transgenic cells, robust ring-like structures were formed after 4 h of heat shock induction. Transient co-expression, confocal imaging, and immunogold electron microscopy (immunogold-EM) experiments demonstrated that these GFP-ARA7(Q69L)-labelled ring-like structures were distinct from the Golgi apparatus and trans-Golgi network, but were labelled with an antibody against an MVB marker protein. In addition, live cell imaging and detailed EM analysis showed that the GFP-ARA7(Q69L)-induced spherical structures originated from the homotypic fusion of MVBs. In summary, it was demonstrated that GFP-ARA7(Q69L) expression is an efficient tool for studying PVC/MVB-mediated protein trafficking and vacuolar degradation in plant cells.

SUBMITTER: Jia T

PROVIDER: S-EPMC3697957 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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ARA7(Q69L) expression in transgenic Arabidopsis cells induces the formation of enlarged multivesicular bodies.

Jia Tianran T Gao Caiji C Cui Yong Y Wang Junqi J Ding Yu Y Cai Yi Y Ueda Takashi T Nakano Akihiko A Jiang Liwen L

Journal of experimental botany 20130516 10

Arabidopsis thaliana ARA7 (AtRabF2b), a member of the plant Rab5 small GTPases functioning in the vacuolar transport pathway, localizes to pre-vacuolar compartments (PVCs), known as multivesicular bodies (MVBs) in plant cells. Overexpression of the constitutively active GTP-bound mutant of ARA7, ARA7(Q69L), induces the formation of large ring-like structures (1-2 µm in diameter). To better understand the biology of these ARA7(Q69L)-induced ring-like structures, transgenic Arabidopsis cell lines ...[more]

PMID: 23682115

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ARA7(Q69L) expression in transgenic Arabidopsis cells induces the formation of enlarged multivesicular bodies.

Publications

ARA7(Q69L) expression in transgenic Arabidopsis cells induces the formation of enlarged multivesicular bodies.

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