Naslov
Chloroplast proteins and PSII photochemistry in young and mature leaves of common fig

Autori
Mlinarić, Selma ; Antunović, Jasenka ; Cesar, Vera ; Lepeduš, Hrvoje

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
The secret life of biomolecules, HDBMB 2010, Book of abstracts / Kovarik, Zrinka ; Varljen, Jadranka - Opatija : Hrvatsko Društvo za Biotehnologiju, 2010, 81-81

Skup
10th Congress of the Croatian Society of Biochemistry and Molecular Biology with international participation

Mjesto i datum
Opatija, Hrvatska, 15.09.2010. - 18.09.2010

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
Ficus carica; photosystem II; photochemistry; chloroplast proteins

Sažetak
Molecular processes involved in photosystem II (PSII) assembly and adaptation to environmental changes remain incompletely understood by now. In this study we investigated differences between young (YL) and mature (ML) leaves of common fig (Ficus carica L.) regarding to the accumulation of main chloroplast proteins (LHCII, D1 and Cytf) involved in light harvesting and electron-transport processes and PSII efficiency with special emphasize to main photochemical processes (light absorption, photon trapping, electron transport and dissipation of excess light energy as heat). Plant material was sampled during the day course at 1 am, 7 am, 1 pm and 7 pm, respectively. Photosynthetic efficiency was assessed by chlorophyll fluorescence measurement (OJIP test). Relative abundances of investigated proteins were determined by densitometry after SDS-PAGE and immunoblotting. Photosynthetic performance index (PI ABS) revealed depression at 1pm in both YL and ML. YL had decreased value of electron transport per reaction center (ETo/RC) at high light conditions (1 pm) while the same parameter remained at same level in ML. Further, dissipation of excess light energy per reaction center (DIo/RC) in YL was markedly increased in respect to ML. These processes were accompanied with differential accumulation of investigated proteins during day course. YL showed increase in LHCII and CYTf levels, while D1 continuously decreased at day light. ML revealed decrease in LHCII level, while Cytf and D1 increased. The availability of certain protein determined photochemical adaptation of PSII in a way to modify certain fraction of reaction centers from active to dissipative ones. This was more emphasized in YL, since ML were able to direct greater fraction of energy into photochemical processes.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Poljoprivreda (agronomija)

POVEZANOST RADA