Here we investigated mechanisms underlying the acclimation to light in the marine angiosperm Posidonia oceanica, along its bathymetric distribution (at -5 m and -25 m), combining molecular and photo-physiological approaches. Analyses were performed during two seasons, summer and autumn, in a meadow located in the Island of Ischia (Gulf of Naples, Italy), where a genetic distinction between plants growing above and below the summer thermocline was previously revealed. At molecular level, analyses carried out using cDNA-microarray and RT-qPCR, revealed the up-regulation of genes involved in photoacclimation (RuBisCO, ferredoxin, chlorophyll binding proteins), and photoprotection (antioxidant enzymes, xanthophyll-cycle related genes, tocopherol biosynthesis) in the upper stand of the meadow, indicating that shallow plants are under stressful light conditions. However, the lack of photodamage, indicates the successful activation of defense mechanisms. This conclusion is also supported by several responses at physiological level as the lower antenna size, the higher number of reaction centers and the higher xanthophyll cycle pigment pool, which are common plant responses to high-light adaptation/acclimation. Deep plants, despite the lower available light, seem to be not light-limited, thanks to some shadeadaptation strategies (e.g. higher antenna size, lower Ekvalues). Furthermore, also at the molecular level there were no signs of stress response, indicating that, although the lower energy available, lowlight environments are more favorable for P. oceanica growth. Globally, results of whole transcriptome analysis displayed two distinct gene expression signatures related to depth distribution, reflecting the different light-adaptation strategies adopted by P. oceanica along the depth gradient. This observation, also taking into account the genetic disjunction of clones along the bathymetry, might have important implications for micro-evolutionary processes happening at meadow scale. Further investigations in controlled conditions must be performed to respond to these questions.

Response of the seagrass Posidonia oceanica to different light environments: Insights from a combined molecular and photo-physiological study / Dattolo, E.; Ruocco, M.; Brunet, C.; Lorenti, M.; Lauritano, C.; D'Esposito, D.; de Luca, P.; Sanges, R.; Mazzuca, S.; Procaccini, G.. - In: MARINE ENVIRONMENTAL RESEARCH. - ISSN 0141-1136. - 101:1(2014), pp. 225-236. [10.1016/j.marenvres.2014.07.010]

Response of the seagrass Posidonia oceanica to different light environments: Insights from a combined molecular and photo-physiological study

Sanges, R.
Membro del Collaboration group
;
2014-01-01

Abstract

Here we investigated mechanisms underlying the acclimation to light in the marine angiosperm Posidonia oceanica, along its bathymetric distribution (at -5 m and -25 m), combining molecular and photo-physiological approaches. Analyses were performed during two seasons, summer and autumn, in a meadow located in the Island of Ischia (Gulf of Naples, Italy), where a genetic distinction between plants growing above and below the summer thermocline was previously revealed. At molecular level, analyses carried out using cDNA-microarray and RT-qPCR, revealed the up-regulation of genes involved in photoacclimation (RuBisCO, ferredoxin, chlorophyll binding proteins), and photoprotection (antioxidant enzymes, xanthophyll-cycle related genes, tocopherol biosynthesis) in the upper stand of the meadow, indicating that shallow plants are under stressful light conditions. However, the lack of photodamage, indicates the successful activation of defense mechanisms. This conclusion is also supported by several responses at physiological level as the lower antenna size, the higher number of reaction centers and the higher xanthophyll cycle pigment pool, which are common plant responses to high-light adaptation/acclimation. Deep plants, despite the lower available light, seem to be not light-limited, thanks to some shadeadaptation strategies (e.g. higher antenna size, lower Ekvalues). Furthermore, also at the molecular level there were no signs of stress response, indicating that, although the lower energy available, lowlight environments are more favorable for P. oceanica growth. Globally, results of whole transcriptome analysis displayed two distinct gene expression signatures related to depth distribution, reflecting the different light-adaptation strategies adopted by P. oceanica along the depth gradient. This observation, also taking into account the genetic disjunction of clones along the bathymetry, might have important implications for micro-evolutionary processes happening at meadow scale. Further investigations in controlled conditions must be performed to respond to these questions.
2014
101
1
225
236
www.elsevier.com/locate/marenvrev
Dattolo, E.; Ruocco, M.; Brunet, C.; Lorenti, M.; Lauritano, C.; D'Esposito, D.; de Luca, P.; Sanges, R.; Mazzuca, S.; Procaccini, G.
File in questo prodotto:
File Dimensione Formato  
dattolo2014.pdf

non disponibili

Tipologia: Versione Editoriale (PDF)
Licenza: Non specificato
Dimensione 972.07 kB
Formato Adobe PDF
972.07 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11767/68490
Citazioni
  • ???jsp.display-item.citation.pmc??? 26
  • Scopus 81
  • ???jsp.display-item.citation.isi??? 77
social impact