Involvement of xanthophyll cycle pigments and glutathione in photoprotection of lichen Umbilicaria antarctica

VRÁBLÍKOVÁ, Hana a Miloš BARTÁK. Involvement of xanthophyll cycle pigments and glutathione in photoprotection of lichen Umbilicaria antarctica. In 14th International congress on photobiology, June 10-15, 2004, Program & Abstracts. Jeju, Korea: Korean Society of Photoscience, 2004, s. 222-222, 299 s.

Základní údaje

Originální název

Involvement of xanthophyll cycle pigments and glutathione in photoprotection of lichen Umbilicaria antarctica

Název česky

Zapojeni pigmentu xantofyloveho cyklu a glutathionu do fotoprotekce lisejniku Umbilicaria antarctica

Autoři

VRÁBLÍKOVÁ, Hana (203 Česká republika) a Miloš BARTÁK (203 Česká republika, garant)

Vydání

Jeju, Korea, 14th International congress on photobiology, June 10-15, 2004, Program & Abstracts, od s. 222-222, 299 s. 2004

Nakladatel

Korean Society of Photoscience

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Další údaje

Jazyk

angličtina

Typ výsledku

Stať ve sborníku

Obor

10600 1.6 Biological sciences

Stát vydavatele

Korejská republika

Utajení

není předmětem státního či obchodního tajemství

Kód RIV

RIV/00216224:14310/04:00010172

Organizační jednotka

Přírodovědecká fakulta

Klíčová slova anglicky

high light stress; lichens; zeaxanthin; glutathione; chlorophyll fluorescence

Štítky

chlorophyll fluorescence, Glutathione, high light stress, lichens, zeaxanthin

Změněno: 10. 2. 2005 11:41, Mgr. Hana Cempírková, Ph.D.

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Anotace

V originále

High light (HL) stress could be expected even in HL-adapted lichens when their thalli, cells of symbiotic photobiont in particular, are exposed to HL in wet state. Among several physiological photoprotective mechanisms activated during such situations, conversion of violaxanthin to zeaxanthin (Z) and capacity of glutathione (GSH) pool are of major importance. Until now, however, changes in GSH pool and its redox state have been studied in lichens only in relation to water stress. Our experiments focused on changes in Z (expressed as de-epoxidation state of xanthophyll cycle pigments - DEPS) and GSH during HL stress imposed on Umbilicaria antarctica. HL stress was induced by applying a strong light of 1800 umol m-2 s-1 for 30 min on hydrated thalli of U. antarctica at 20degC. Timecourse of HL stress and recovery was monitored by chlorophyll fluorescence (maximal quantum yield, Fv/Fm, non-photochemical quenching, NPQ). HL stress led to a photoinhibition demonstrated as a decrease of Fv/Fm and an increase in NPQ. During subsequent 10 h recovery under low light, Fv/Fm and NPQ recovered almost to pre-photoinhibitory levels. HL-induced increase in DEPS, maximum of which was recorded immediately after HL exposure. Then, DEPS decreased during 10 h to initial level. Total GSH strongly decreased after HL and proportion of its oxidised to reduced form slightly increased. During 10 h recovery, total GSH did not increase to initial value indicating that re-synthesis of GSH was not completed.

Česky

Mezi fyziologicke fotoprotektivni mechanismy, chranici lisejniky pred svetelnym stresem, patri konverze violaxantinu na zeaxantin a kapacita antioxidacni molekuly glutathionu.

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Návaznosti

GA522/03/0754, projekt VaV	Název: Fotoinhibice a fotoochrana u lišejníků v extrémních podmínkách Investor: Grantová agentura ČR, Fotoinhibice a fotoochrana u lišejníků v extrémních podmínkách
MSM 143100007, záměr	Název: Ekologie pobřežní antarktické vegetační oázy Investor: Ministerstvo školství, mládeže a tělovýchovy ČR, Ekologie pobřežní antarktické vegetační oázy