TY - JOUR
T1 - Effects of natural radiation, photosynthetically active radiation and artificial ultraviolet radiation-b on the chloroplast organization and metabolism of porphyra acanthophora var. brasiliensis (rhodophyta, bangiales)
AU - Bouzon, Zenilda L.
AU - Chow, Fungyi
AU - Zitta, Carmen S.
AU - Dos Santos, Rodrigo W.
AU - Ouriques, Luciane C.
AU - Marthiellen, Marthiellen R.
AU - Osorio, Luz K P
AU - Gouveia, Claudiane
AU - De Paula Martins, Roberta
AU - Latini, Alexandra
AU - Ramlov, Fernanda
AU - Maraschin, Marcelo
AU - Schmidt, Eder C.
PY - 2012/12
Y1 - 2012/12
N2 - We undertook a study of Porphyra acanthophora var. brasiliensis to determine its responses under ambient conditions, photosynthetically active radiation (PAR), and PAR+UVBR (ultraviolet radiation-B) treatment, focusing on changes in ultrastructure, and cytochemistry. Accordingly, control ambient samples were collected in the field, and two different treatments were performed in the laboratory. Plants were exposed to PAR at 60 μmol photons m -2 s-1 and PAR + UVBR at 0.35 W m-2 for 3 h per day during 21 days of in vitro cultivation. Confocal laser scanning microscopy analysis of the vegetative cells showed single stellate chloroplast in ambient and PAR samples, but in PAR+UVBR-exposed plants, the chloroplast showed alterations in the number and form of arms. Under PAR+UVBR treatment, the thylakoids of the chloroplasts were disrupted, and an increase in the number of plastoglobuli was observed, in addition to mitochondria, which appeared with irregular, disrupted morphology compared to ambient and PAR samples. After UVBR exposure, the formation of carpospores was also observed. Plants under ambient conditions, as well as those treated with PAR and PAR+UVBR, all showed different concentrations of enzymatic response, including glutathione peroxidase and reductase activity. In summary, the present study demonstrates that P. acanthophora var. brasiliensis shows the activation of distinct mechanisms against natural radiation, PAR and PAR+UVBR.
AB - We undertook a study of Porphyra acanthophora var. brasiliensis to determine its responses under ambient conditions, photosynthetically active radiation (PAR), and PAR+UVBR (ultraviolet radiation-B) treatment, focusing on changes in ultrastructure, and cytochemistry. Accordingly, control ambient samples were collected in the field, and two different treatments were performed in the laboratory. Plants were exposed to PAR at 60 μmol photons m -2 s-1 and PAR + UVBR at 0.35 W m-2 for 3 h per day during 21 days of in vitro cultivation. Confocal laser scanning microscopy analysis of the vegetative cells showed single stellate chloroplast in ambient and PAR samples, but in PAR+UVBR-exposed plants, the chloroplast showed alterations in the number and form of arms. Under PAR+UVBR treatment, the thylakoids of the chloroplasts were disrupted, and an increase in the number of plastoglobuli was observed, in addition to mitochondria, which appeared with irregular, disrupted morphology compared to ambient and PAR samples. After UVBR exposure, the formation of carpospores was also observed. Plants under ambient conditions, as well as those treated with PAR and PAR+UVBR, all showed different concentrations of enzymatic response, including glutathione peroxidase and reductase activity. In summary, the present study demonstrates that P. acanthophora var. brasiliensis shows the activation of distinct mechanisms against natural radiation, PAR and PAR+UVBR.
KW - carpospores
KW - chloroplasts
KW - enzymatic response
KW - photosynthetic pigments
KW - Porphyra acanthophora var. brasiliensis
KW - ultraviolet radiation-B
UR - http://www.scopus.com/inward/record.url?scp=84871510365&partnerID=8YFLogxK
U2 - 10.1017/S1431927612013359
DO - 10.1017/S1431927612013359
M3 - Article
C2 - 23153514
AN - SCOPUS:84871510365
VL - 18
SP - 1467
EP - 1479
JO - Microscopy and Microanalysis
JF - Microscopy and Microanalysis
SN - 1431-9276
IS - 6
ER -