Evidence for a role of raffinose in stabilizing photosystem II during freeze-thaw cycles

0376209 - ÚVGZ 2012 RIV DE eng J - Článek v odborném periodiku
Knaupp, M. - Mishra, Kumud - Nedbal, Ladislav - Heyer, A. G.
Evidence for a role of raffinose in stabilizing photosystem II during freeze-thaw cycles.
Planta. Roč. 234, č. 3 (2011), s. 477-486. ISSN 0032-0935. E-ISSN 1432-2048
Grant CEP: GA MŠMT 2B06068; GA MŠMT OC08055
Výzkumný záměr: CEZ:AV0Z60870520
Klíčová slova: arabidopsis * cold tolerance * freezing damage * raffinose * chlorophyll fluorescence
Kód oboru RIV: EH - Ekologie - společenstva
Impakt faktor: 3.000, rok: 2011

A role of non-reducing sugars like sucrose and raffinose in the protection of plant cells against damage during freezing has been proposed for many species, but reports on physiological effects are conflicting. Non-aqueous fractionation of mesophyll cell compartments in Arabidopsis thaliana was used to show that sucrose and raffinose accumulate in plastids during low temperatures, pointing to a physiological role in protecting the photosynthetic apparatus. Comparing a previously described raffinose synthase (RS) mutant of A. thaliana with its corresponding wild type, accession Col-0, revealed that a lack of raffinose has no effect on electrolyte leakage from leaf cells after freeze-thaw cycles, supporting that raffinose is not essential for protecting the plasma membrane. However, in situ chlorophyll fluorescence showed that maximum quantum yield of PS II photochemistry (F (v)/F (m)) and other fluorescence parameters of cold acclimated leaves subjected to freeze-thaw cycles were significantly lower in the raffinose synthase mutant than in the corresponding wild type, indicating that raffinose is involved in stabilizing PS II of cold acclimated leaf cells against damage during freezing.
Trvalý link: http://hdl.handle.net/11104/0208672