Exchange of Protein Molecules Through Connections Between Higher Plant Plastids
Abstract
Individual plastids of vascular plants have generally been considered to be discrete autonomous entities that do not directly communicate with each other. However, in transgenic plants in which the plastid stroma was labeled with green fluorescent protein (GFP), thin tubular projections emanated from individual plastids and sometimes connected to other plastids. Flow of GFP between interconnected plastids could be observed when a single plastid or an interconnecting plastid tubule was photobleached and the loss of green fluorescence by both plastids was seen. These tubules allow the exchange of molecules within an interplastid communication system, which may facilitate the coordination of plastid activities.
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REFERENCES AND NOTES
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We thank J. Haseloff for the mGFP4 gene and T. Horiagon, R. Last, S. Lawrence, and K. Cline for antibodies to GFP, AS, and LHCP. Supported by DOE Energy Biosciences Program grant DE-FG02-89ER14030 to M.R.H. and grants to W.W.W. and Developmental Resources for Biophysical Imaging and Opto-electronics by NSF (DIR8800278) and NIH (RR04224 and R07719).
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Published In
Science
Volume 276 | Issue 5321
27 June 1997
27 June 1997
Submission history
Received: 15 January 1997
Accepted: 9 May 1997
Published in print: 27 June 1997
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