UVB Effects on the Photosystem II-D1 Protein of Phytoplankton and Natural Phytoplankton Communities

@article{citeulike:2647457, abstract = {ABSTRACT The reaction center of photosystem II is susceptible to photodamage. In particular the D1 protein located in the photosystem II core has a rapid, light-dependent turnover termed the photosystem II repair cycle that, under illumination, degrades and resynthesizes D1 protein to limit accumulation of photodamaged photosystem II. Most studies concerning the effects of UVB (280-320 nm) on this cycle have been on cyanobacteria or specific phytoplankton species rather than on natural communities of phytoplankton. During a 5-year multidisciplinary project on the effects of UV radiation (200-400 nm) on natural systems, the effects of UVB on the D1 protein of natural phytoplankton communities were assessed. This review provides an overview of photo-inhibitory effects of light on cultured and natural phytoplankton, with an emphasis on the interrelation of UVB exposure, D1 protein degradation and the repair of photosystem II through D1 resynthesis. Although the UVB component of the solar spectrum contributes to the primary photoinactivation of photosystem II, we conclude that, in natural communities, inhibition of the rate of the photosystem II repair cycle is a more important influence of UVB on primary productivity. Indeed, exposing tropical and temperate phytoplankton communities to supplemented UVB had more inhibitory effect on D1 synthesis than on the D1 degradation process itself. However, the rate of net D1 damage was faster for the tropical communities, likely because of the effects of high ambient light and water temperature on mechanisms of protein degradation and synthesis.}, author = {Bouchard, Josee N. and Roy, Suzanne and Campbell, Douglas A. }, citeulike-article-id = {2647457}, doi = {10.1562/2005-08-31-IR-666}, journal = {Photochemistry and Photobiology}, number = {4}, pages = {936--951}, posted-at = {2008-04-09 23:44:18}, priority = {3}, title = {UVB Effects on the Photosystem II-D1 Protein of Phytoplankton and Natural Phytoplankton Communities}, url = {http://www.blackwell-synergy.com/doi/abs/10.1562/2005-08-31-IR-666}, volume = {82}, year = {2006} }

TY - JOUR ID - citeulike:2647457 L3 - citeulike-article-id:2647457 TI - UVB Effects on the Photosystem II-D1 Protein of Phytoplankton and Natural Phytoplankton Communities JF - Photochemistry and Photobiology VL - 82 IS - 4 SP - 936 EP - 951 N2 - ABSTRACT The reaction center of photosystem II is susceptible to photodamage. In particular the D1 protein located in the photosystem II core has a rapid, light-dependent turnover termed the photosystem II repair cycle that, under illumination, degrades and resynthesizes D1 protein to limit accumulation of photodamaged photosystem II. Most studies concerning the effects of UVB (280-320 nm) on this cycle have been on cyanobacteria or specific phytoplankton species rather than on natural communities of phytoplankton. During a 5-year multidisciplinary project on the effects of UV radiation (200-400 nm) on natural systems, the effects of UVB on the D1 protein of natural phytoplankton communities were assessed. This review provides an overview of photo-inhibitory effects of light on cultured and natural phytoplankton, with an emphasis on the interrelation of UVB exposure, D1 protein degradation and the repair of photosystem II through D1 resynthesis. Although the UVB component of the solar spectrum contributes to the primary photoinactivation of photosystem II, we conclude that, in natural communities, inhibition of the rate of the photosystem II repair cycle is a more important influence of UVB on primary productivity. Indeed, exposing tropical and temperate phytoplankton communities to supplemented UVB had more inhibitory effect on D1 synthesis than on the D1 degradation process itself. However, the rate of net D1 damage was faster for the tropical communities, likely because of the effects of high ambient light and water temperature on mechanisms of protein degradation and synthesis. AU - Bouchard, Josee AU - Roy, Suzanne AU - Campbell, Douglas PY - 2006/// UR - http://www.blackwell-synergy.com/doi/abs/10.1562/2005-08-31-IR-666 ER -