Naslov
TROL-FNR interaction reveals alternative pathways of electron partitioning in photosynthesis

Autori
Vojta, Lea ; Carić, Dejana ; Cesar, Vera ; Antunović Dunić, Jasenka ; Lepeduš, Hrvoje ; Kveder, Marina ; Fulgosi, Hrvoje

Izvornik
Scientific reports (2045-2322) 5 (2015); 10085, 9

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
photosynthetic electron transport ; Photosystem I ; ROS ; electron paramagnetic resonance

Sažetak
In photosynthesis, final electron transfer from ferredoxin to NADP+ is accomplished by the flavo enzyme ferredoxin:NADP+ oxidoreductase (FNR). FNR is recruited to thylakoid membranes via integral membrane thylakoid rhodanase-like protein TROL. We address the fate of electrons downstream of photosystem I when TROL is absent. We have employed electron paramagnetic resonance (EPR) spectroscopy to study free radical formation and electron partitioning in TROL-depleted chloroplasts. DMPO was used to detect superoxide anion (O2.−) formation, while the generation of other free radicals was monitored by Tiron. Chloroplasts from trol plants pre-acclimated to different light conditions consistently exhibited diminished O2.− accumulation. Generation of other radical forms was elevated in trol chloroplasts in all tested conditions, except for the plants pre-acclimated to high-light. Remarkably, dark- and growth light-acclimated trol chloroplasts were resilient to O2.− generation induced by methyl-viologen. We propose that the dynamic binding and release of FNR from TROL can control the flow of photosynthetic electrons prior to activation of the pseudo-cyclic electron transfer pathway.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA