Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Chloroplast Biogenesis Is Regulated by Direct Action of the Ubiquitin-Proteasome System
Ist Teil von
Science (American Association for the Advancement of Science), 2012-11, Vol.338 (6107), p.655-659
Ort / Verlag
Washington, DC: American Association for the Advancement of Science
Erscheinungsjahr
2012
Quelle
MEDLINE
Beschreibungen/Notizen
Development of chloroplasts and other plastids depends on the import of thousands of nucleus-encoded proteins from the cytosoL Import is initiated by TOC (translocon at the outer envelope of chloroplasts) complexes in the plastid outer membrane that incorporate multiple, client-specific receptors. Modulation of import is thought to control the plastid's proteome, developmental fate, and functions. Using forward genetics, we identified Arabidopsis SP1, which encodes a RING-type ubiquitin E3 ligase of the chloroplast outer membrane. The SP1 protein associated with TOC complexes and mediated ubiquitination of TOC components, promoting their degradation. Mutant sp1 plants performed developmental transitions that involve plastid proteome changes inefficiently, indicating a requirement for reorganization of the TOC machinery. Thus, the ubiquitin-proteasome system acts on plastids to control their development.