CC/NUMBER 26 This Week’s Citation Classic® IUNE 27, 1988 Douce R & .Joyard J. Structure and function of the envelope. Advan, Bofan. Res. 7:1-116, 1979. F lLaboratoire de Biologie Vdgdtale. CEA—Centre dEludes Nucltaires. . Francel The plastid envelope has received little attention de- lactosyldiacylglycerol, or MG DC) were described in spite its importance in the functional and structural these first articles. integrity ofthe . In this review we discuss When Douce came to Grenoble, the work was the structure, isolation, chemical composition, and continued together with joyard, who started his the- origin of the higher plant chloroplast envelope. [The sison envelopemembranes. A complete study ofen- SC/a indicates that this paper has been cited in over velope properties, a comparison with envelope mem- 130 publications.) branes from other , was undertaken. This work is still in progress almost 15 years later! Our idea was that since envelope membranes are a per- manent structure in all plastids analyzed so far and contain specific plastid components(, pigments, Roland Douce and Jacques Joyard quinones, and so on), they should play a malor role Laboratoire de Physiologic Cellulaire in plastid biogenesis. Indeed, we3have demonstrated Végétale that this hypothesis was true, and we have de- (Unite Associée au CNRS n°576) scribed, in envelope membranes, more than 20 Département de Recherche Fondamentale enzymes involved in 4the biosynthesis of plastid lipids Centre d’Etudes Nudéairee et and prenylquinones. Université Joseph Fourier We are convinced that the paper has been cited 85 X, F-38041 Grenoble mostly because we tried to present an exhaustive France view of the problems related to envelope mem- branes: Structure, interaction with the other cell April 8, 1988 membranes, chemical composition, role in metabo- lite transport and regulationof photosynthesis, role in the biosynthesis ofplastid lipids, role in the trans- HW. Woolhouse, the editor of Advances in Bo- port of plastid that are synthesized on cy- tanical Research, considering the fact that more toribosomes, origin of envelope membranes, and so work had been published on the erythrocyte mem- on. Thus, in this review, we have presented together branethan all the types of plant cell membranes put numerous ideas that indeed stimulated research in together, asked for a review to provide an introduc- the field. 1- tion to the study of the chloroplast envelope mem- Almost 10 years after this review, we are still 5. branes. working on envelope4-7membranes. Significant prog4- The review was mostly based on the work done ress has been made, and a more recent review first by Roland Douce duringpostdoctoral work at details all the properties and enzymesthat have been the Scripps Institution of Oceanography (La jolla, demonstrated on the outer or the inner envelope California) under the supervision of Andrew A. membranes that can now be separated. We are still Benson and then in collaboration with Jacques fascinated by this unique membrane system. But 5:: Joyard at Grenoble Nuclear Center and University1 what we feel most important to mention is that the (France). During the initial work with Benson, a two authors of theoriginal reviewon chloroplast en- method was developed for the preparation of velope membranes are still working together, are envelope membranes devoid of contaminants from good friends, and are still trying to understand this other plastidial and extraplastidial compartments. membrane system together with a limited number The polar composition, the presence of of people: M.A. Block, A.J. Dome, and, more recent- carotenoids, and the characterization of specific ly, C. Alban. We are convinced that this was the key markers for envelope membranes2 (a Mg~-depen- for improving our knowledge of plastid envelope dent ATPase’ and an enzyme responsible for the membranes, which was still very much in its infancy biosynthesisof the major plant polar lipid: monoga- when we wrote this review.

1. Deuce R, Holtz R B & Beisco A A. Isolation and properties of the envelope of spinach chloroplasls. I. Best. Cheni. 248:7215-22, t973. (Cited 235 times.) 2. Douce R. Site of biosynthesis of gatactolipids in spinach . Science 183:852-3, 1974. (Cited ItO times.) 3. Joyard i & Douce R. Site of synthesis of phosphatidic acid and diacylglycerol in spinach chioroplasts. Biocbiin. Biop6ys. Acts 486:273-85. 1977. (Cited 85 times.) 4. Deuce R, Block M A. Borne A J & JoyardJ. The plastid envelope membranes: their seucture, composttton. and role in chloroplast biogenesis. SubceJL Biochem. 10:1-84, 1984. 5. Joyard 3, Blllecocq A, Bartlett S C, Block M A, Deuce It & Chue N H. Localization ofpolypeptides to the cyeosolic side of the outer envelope membrane of spinach chloroplusts. J. BioI. Chem. 258:10000-6, 1983. 6. Block M A, Dome A 3. Joyard 3 & Deuce R. Preparation and characterization of membrane fractions enrichni in outer and inner envelope membranes from spinach chloroptasts. 1. Electrophoretic and intmunochentical analyses. J. Biol. Chew. 258:13273-SO, 1983. 7. Ptnesu B, Dubertret G, Joyard J & Deuce It. Fluorescence properties of the envelope membranes from spinach chtoroplasts. Detection of peotochiorophyltide. I. Biol. Chem. 261:9210-5, 1986.

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