Three-dimensional reconstruction of anomalous chloroplasts in transgenic ipt tobacco

• Published in: Planta Vol. 223; no. 4; pp. 659 - 671
• Main Authors: Synková, Helena, Schnablová, Renáta, Polanská, Lenka, Hušák, Michal, Šiffel, Pavel, Vácha, František, Malbeck, Jiří, Macháčková, Ivana, Nebesářová, Jana
• Format: Journal Article
• Language: English
• Published: Berlin Springer-Verlag 01.03.2006; Springer; Springer Nature B.V
• Subjects: Alkyl and Aryl Transferases - genetics; Alkyl and Aryl Transferases - metabolism; Biological and medical sciences; Biotechnology; Chlorophylls; Chloroplasts; Chloroplasts - genetics; Chloroplasts - metabolism; Chloroplasts - ultrastructure; Crystals; Cytokinins; Cytokinins - genetics; Cytokinins - metabolism; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant; Genes, Plant - genetics; Genetic engineering; Genetic technics; Leaves; Metabolites; Methods. Procedures. Technologies; Nicotiana - cytology; Nicotiana - enzymology; Nicotiana - genetics; Nicotiana - metabolism; Plant cells; Plants; Plants, Genetically Modified; Plastids; Reticulum; Tobacco; Transgenes - genetics; Transgenic animals and transgenic plants; Transgenic plants; Plant leaf; Chlorophyll b; Nicotiana tabacum; Ipt; Cytokinin; Chlorophyll a; Cytokinins; Mitochondria; Ultrastructure; Dicotyledones; Angiospermae; Peroxisome; Nicotiana tabacum L; Spermatophyta; Solanaceae; Chloroplast; Crystalloids; LHC II aggregates
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-005-0119-6

Anomalies in the ultrastructure of chloroplasts, from transgenic ipt tobacco, overproducing endogenous cytokinins (CKs) were studied. Detailed analyses of CKs and their metabolites showed that Pssu-ipt tobacco contained enhanced contents of CKs both in leaves and in isolated chloroplasts. The role of CKs in the formation of anomalous structures is suggested. Pssu-ipt chloroplasts frequently formed the distinct peripheral reticulum with a system of caverns that often involved mitochondria and/or peroxisomes. Large crystalloids, which were found in chloroplasts of Pssu-ipt, occupied up to 16% of chloroplast volume. We suggested that the crystalloids were formed by LHC II aggregates. This was supported by analysis of the fluorescence emission spectra at 77°K, chlorophyll a/b ratio, immunogold staining of the structures, and crystallographic unit size analysis.