Molecular characterization of CDSP 34, a chloroplastic protein induced by water deficit inSolanum tuberosumL. plants, and regulation ofCDSP 34expression by ABA and high illumination
We previously described the accumulation of a 34 kDa thylakoid protein, named CDSP 34 for chloroplastic drought-induced stress protein, inSolanum tuberosumplants subjected to water deficit. A full-length CDSP 34 cDNA has been isolated and we report here that mature CDSP 34 is highly similar to two chromoplastic proteins, fibrillin fromCapsicum annuum andCHRC (for chromoplast protein C) fromCucumis sativus, components of carotenoid-accumulating structures. Northern and Western analyses showed that both CDSP 34 transcript and protein accumulated from early stages of water deficit. In water-stressed tomato plants, similar increases in the CDSP 34-related transcript amount were noticed in wild-type and ABA-deficientflaccamutant, but protein accumulation was observed only in wild-type, suggesting a post-transcriptional role of ABA in CDSP 34 synthesis regulation. Substantial increases in CDSP 34 transcript and protein abundances were also observed in potato plants subjected to high illumination. The CDSP 34 protein is proposed to play a structural role in stabilizing stromal lamellae thylakoids upon osmotic or oxidative stress.
Document Type: Short Communication
Affiliations: CEA/Cadarache, DSV, Laboratoire d’Ecophysiologie de la Photosynthèse, Département d’Ecophysiologie Végétale et de Microbiologie, Bâtiment 161, 13108 Saint-Paul-lez-Durance, France
Publication date: October 1, 1998