Meyer, C-L; Peisker, D; Courbot, M; Cracium, A-R; Cazalé, A-C; Desgain, D; Schat, H; Clemens, S; Verbruggen, N: Isolation and characterization of Arabidopsis halleri and Thlaspi caerulescens phytochelatin synthases, Planta (2011), doi:10.1007/s00425-011-1378-z
Abstract:
The synthesis of phytochelatins (PC) represents a major metal and metalloid detoxification mechanism in various species. PC most likely play a role in the distribution and accumulation of Cd and possibly other metals. However, to date, no studies have investigated the phytochelatin synthase (PCS) genes and their expression in the Cd-hyperaccumulating species. We used functional screens in two yeast species to identify genes expressed by two Cd hyperaccumulators (Arabidopsis halleri and Thlaspi caerulescens) and involved in cellular Cd tolerance. As a result of these screens, PCS genes were identified for both species. PCS1 was in each case the dominating cDNA isolated. The deduced sequences of AhPCS1 and TcPCS1 are very similar to AtPCS1 and their identity is particularly high in the proposed catalytic N-terminal domain. We also identified in A. halleri and T. caerulescens orthologues of AtPCS2 that encode functional PCS. As compared to A. halleri and A. thaliana, T. caerulescens showed the lowest PCS expression. Furthermore, concentrations of PC in Cd-treated roots were the highest in A. thaliana, intermediate in A. halleri and the lowest in T. caerulescens. This mirrors the known capacity of these species to translocate Cd to the shoot, with T. caerulescens being the best translocator. Very low or undetectable concentrations of PC were measured in A. halleri and T. caerulescens shoots, contrary to A. thaliana. These results suggest that extremely efficient alternative Cd sequestration pathways in leaves of Cd hyperaccumulators prevent activation of PC synthase by Cd2+ ions.
Upcoming ...


BayCEER Colloquium:
Th. 2024-04-18
The Canvas of Change: Creative Marketing for Behaviour Change, Sustainability and Social Good
Th. 2024-04-18
Survival, 'dormancy', and resuscitation of microorganisms in water-limited environments: insights from coastal salt flats and desert soil crusts
BayCEER Short Courses:
Tu. 2024-04-16
Geographical information system and R environment for conservation biology
Ecological-Botanical Garden:
Su. 2024-04-07
Führung | Talking Tree: Was Bäume über´s Klima erzählen
Fr. 2024-04-19
Führung | Gesteine im Ökologisch-Botanischen Garten
Weather research site
Luftdruck (356m): 950.4 hPa
Lufttemperatur: 8.2 °C
Niederschlag: 5.2 mm/24h
Sonnenschein: 2 h/d

...more
Globalstrahlung: 68 W/m²
Lufttemperatur: 3.8 °C
Niederschlag: 3.6 mm/24h
Wind (Höhe 32m): 16.3 km/h

...more
This site makes use of cookies More information