Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Photosynthetic performance, DNA damage and repair in gametes of the endemic Antarctic brown alga Ascoseira mirabilis exposed to ultraviolet radiation
Show others and affiliations
Responsible organisation
2007 (English)In: Austral ecology (Print), ISSN 1442-9985, E-ISSN 1442-9993, Vol. 32, no 8, 917-926 p.Article in journal (Refereed) Published
Resource type
Text
Abstract [en]

Stress physiology on the reproductive cells of Antarctic macroalgae remained unstudied. Ascoseira mirabilis is endemic to the Antarctic region, an isolated ecosystem exposed to extreme environmental conditions. Moreover, stratospheric ozone depletion leads to increasing ultraviolet radiation (280-400 nm) at the earth's surface, thus it is necessary to investigate the capacity of reproductive cells to cope with different UV irradiances. This study is aimed to investigate the impact of exposure to different spectral irradiance on the photosynthetic performance, DNA damage and gamete morphology of the A. mirabilis. Gametangia, gametes and zygotes of the upper sublittoral brown alga A. mirabilis were exposed to photosynthetically active radiation (PAR = P; 400-700 nm), P + UV-A radiation (UV-A, 320-400 nm) and P + UV-A + UV-B radiation (UV-B, 280-320 nm). Rapid photosynthesis versus irradiance curves of freshly released propagules were measured. Photosynthetic efficiencies and DNA damage (in terms of cyclobutane pyrimidine dimers) were determined after 1, 2, 4 and 8 h exposure as well as after 2 days of recovery in dim white light. Saturation irradiance (I(k)) in freshly released propagules was 52 mu mol photons m(-2) s(-1). Exposure for 1 h under 22 mu mol photons m(-2) s(-1) of PAR significantly reduced the optimum quantum yield (F(v)/F(m)), suggesting that propagules are low light adapted. Furthermore, UVR significantly contributed to the photoinhibition of photosynthesis. Increasing dose as a function of exposure time additionally exacerbated the effects of different light treatments. The amount of DNA damage increased with the UV-B dose but an efficient repair mechanism was observed in gametes pre-exposed to a dose lower than 5.8 x 10(3) J m(-2) of UV-B. The results of this study demonstrate the negative impact of UV-B radiation. However, gametes of A. mirabilis are capable of photosynthetic recovery and DNA repair when the stress factor is removed. This capacity was observed to be dependent on the fitness of the parental sporophyte.

Place, publisher, year, edition, pages
Alfred Wegener Inst Polar & Marine Res, Biol Anstalt Helgoland, Marine Stn, Helgoland, Germany. Univ Kiel, Inst Polar Ecol, D-24148 Kiel, Germany. Alfred Wegener Inst Polar & Marine Res, Sect Seaweed Biol, Bremerhaven, Germany. Univ Hamburg, Biozentrum Klein Flottbek, Hamburg, Germany. Univ Gothenburg, Dept Marine Ecol, Gothenburg, Sweden., 2007. Vol. 32, no 8, 917-926 p.
Keyword [en]
Ascoseira mirabilis, cyclobutane pyrimidine dimer, optimum quantum yield, photosynthetic recovery, P-I curve
Research subject
SWEDARP; SWEDARP 2004/05, UV-strålningens effekter på bentiska primärproducenter i Antarktis
Identifiers
URN: urn:nbn:se:polar:diva-2566DOI: 10.1111/j.1442-9993.2007.01796.xISI: 000250760700009OAI: oai:DiVA.org:polar-2566DiVA: diva2:883196
Available from: 2015-12-16 Created: 2015-12-16 Last updated: 2017-12-01

Open Access in DiVA

No full text

Other links

Publisher's full text
In the same journal
Austral ecology (Print)

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 13 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf