Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία
The depletion of stratospheric ozone over the Antarctic and Arctic has been observed since 1974 and 1990, respectively. The principal consequence of stratospheric ozone depletion is the increase in ultraviolet B (UVB: 280-320 nm) radiation reaching the Earth's surface. The potential impact of t...
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University of Crete (UOC)
2006
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Online Access: | http://hdl.handle.net/10442/hedi/16141 https://doi.org/10.12681/eadd/16141 |
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fthedi:oai:10442/16141 2024-06-23T07:47:40+00:00 Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία Regulatory mechanisms of the photosynthetic apparatus sensitivity / tolerance to UVB radiation Sfichi, Liliana 2006 http://hdl.handle.net/10442/hedi/16141 https://doi.org/10.12681/eadd/16141 eng eng University of Crete (UOC) Πανεπιστήμιο Κρήτης doi:10.12681/eadd/16141 http://hdl.handle.net/10442/hedi/16141 Φωτοσυνθετικός μηχανισμός UVB ακτινοβολία PAR ακτινοβολία Πολυαμίνες Φωτοσύστημα ΙΙ Καροτινοειδή Photosynthetic apparatus UVB radiation PAR Polyamines LUCU PS II Carotenoids Scenedesmus obliquus Φυσικές Επιστήμες Βιολογία Natural Sciences Biological Sciences PhD Thesis 2006 fthedi https://doi.org/10.12681/eadd/16141 2024-06-04T14:34:46Z The depletion of stratospheric ozone over the Antarctic and Arctic has been observed since 1974 and 1990, respectively. The principal consequence of stratospheric ozone depletion is the increase in ultraviolet B (UVB: 280-320 nm) radiation reaching the Earth's surface. The potential impact of the enhanced solar UVB radiation predicted by atmospheric models has been the subject of investigation for the last two decades. The data collected from various reports involves roughly 300 species and varieties of plants. Around one-third to one-half of these plants showed physiological damage and/or growth reductions in response to UVB. Many studies have identified PSII as the most labile component of the photosynthetic apparatus to elevated UVB radiation. Still now the underlying mechanisms are a controversial subject that makes difficult to evaluate the environmental relevance of UVB effects on photosynthesis. Several different target sites have been proposed. These include the reaction center of PSII, the light harvesting complex (LHCII) and the acceptor/donor side of PSII. In spite of the great amount of research devoted to the effects of UVB radiation on plants during the past decades, efforts are still needed to clarify the molecular background of the UVB damage, as well as the protective and repair mechanisms. The primary target of UVB radiation in the photosynthetic apparatus is not clearly established. In addition, there are discrepancies between laboratory and field studies that make it difficult to estimate how much the projected increase in UVB radiation at the Earth’s surface will affect photosynthesis. In this context, this work was focused on the factors determining the sensitivity/tolerance of the photosynthetic apparatus to UVB and their regulation. The investigations were carried out in cultures of wt and wt-lhc mutant (similar to wt but without LHCII) of Scenedesmus obliquus. The results demonstrate that there is a fine mechanism that regulates the photosynthetic behavior to UVB radiation. This ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Arctic National Archive of PhD Theses (National Documentation Centre Greece) Antarctic Arctic The Antarctic |
institution |
Open Polar |
collection |
National Archive of PhD Theses (National Documentation Centre Greece) |
op_collection_id |
fthedi |
language |
English |
topic |
Φωτοσυνθετικός μηχανισμός UVB ακτινοβολία PAR ακτινοβολία Πολυαμίνες Φωτοσύστημα ΙΙ Καροτινοειδή Photosynthetic apparatus UVB radiation PAR Polyamines LUCU PS II Carotenoids Scenedesmus obliquus Φυσικές Επιστήμες Βιολογία Natural Sciences Biological Sciences |
spellingShingle |
Φωτοσυνθετικός μηχανισμός UVB ακτινοβολία PAR ακτινοβολία Πολυαμίνες Φωτοσύστημα ΙΙ Καροτινοειδή Photosynthetic apparatus UVB radiation PAR Polyamines LUCU PS II Carotenoids Scenedesmus obliquus Φυσικές Επιστήμες Βιολογία Natural Sciences Biological Sciences Sfichi, Liliana Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
topic_facet |
Φωτοσυνθετικός μηχανισμός UVB ακτινοβολία PAR ακτινοβολία Πολυαμίνες Φωτοσύστημα ΙΙ Καροτινοειδή Photosynthetic apparatus UVB radiation PAR Polyamines LUCU PS II Carotenoids Scenedesmus obliquus Φυσικές Επιστήμες Βιολογία Natural Sciences Biological Sciences |
description |
The depletion of stratospheric ozone over the Antarctic and Arctic has been observed since 1974 and 1990, respectively. The principal consequence of stratospheric ozone depletion is the increase in ultraviolet B (UVB: 280-320 nm) radiation reaching the Earth's surface. The potential impact of the enhanced solar UVB radiation predicted by atmospheric models has been the subject of investigation for the last two decades. The data collected from various reports involves roughly 300 species and varieties of plants. Around one-third to one-half of these plants showed physiological damage and/or growth reductions in response to UVB. Many studies have identified PSII as the most labile component of the photosynthetic apparatus to elevated UVB radiation. Still now the underlying mechanisms are a controversial subject that makes difficult to evaluate the environmental relevance of UVB effects on photosynthesis. Several different target sites have been proposed. These include the reaction center of PSII, the light harvesting complex (LHCII) and the acceptor/donor side of PSII. In spite of the great amount of research devoted to the effects of UVB radiation on plants during the past decades, efforts are still needed to clarify the molecular background of the UVB damage, as well as the protective and repair mechanisms. The primary target of UVB radiation in the photosynthetic apparatus is not clearly established. In addition, there are discrepancies between laboratory and field studies that make it difficult to estimate how much the projected increase in UVB radiation at the Earth’s surface will affect photosynthesis. In this context, this work was focused on the factors determining the sensitivity/tolerance of the photosynthetic apparatus to UVB and their regulation. The investigations were carried out in cultures of wt and wt-lhc mutant (similar to wt but without LHCII) of Scenedesmus obliquus. The results demonstrate that there is a fine mechanism that regulates the photosynthetic behavior to UVB radiation. This ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Sfichi, Liliana |
author_facet |
Sfichi, Liliana |
author_sort |
Sfichi, Liliana |
title |
Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
title_short |
Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
title_full |
Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
title_fullStr |
Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
title_full_unstemmed |
Ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην UVB ακτινοβολία |
title_sort |
ρυθμιστικοί μηχανισμοί της ευαισθησίας / ανθεκτικότητας του φωτοσυνθετικού μηχανισμού στην uvb ακτινοβολία |
publisher |
University of Crete (UOC) |
publishDate |
2006 |
url |
http://hdl.handle.net/10442/hedi/16141 https://doi.org/10.12681/eadd/16141 |
geographic |
Antarctic Arctic The Antarctic |
geographic_facet |
Antarctic Arctic The Antarctic |
genre |
Antarc* Antarctic Arctic |
genre_facet |
Antarc* Antarctic Arctic |
op_relation |
doi:10.12681/eadd/16141 http://hdl.handle.net/10442/hedi/16141 |
op_doi |
https://doi.org/10.12681/eadd/16141 |
_version_ |
1802651820337659904 |