Antisense inhibition of protein phosphatase 2C accelerates cold acclimation in Arabidopsis thaliana

Citation
S. Tahtiharju et T. Palva, Antisense inhibition of protein phosphatase 2C accelerates cold acclimation in Arabidopsis thaliana, PLANT J, 26(4), 2001, pp. 461-470
Citations number
45
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences","Animal & Plant Sciences
Journal title
PLANT JOURNAL
ISSN journal
0960-7412 → ACNP
Volume
26
Issue
4
Year of publication
2001
Pages
461 - 470
Database
ISI
SICI code
0960-7412(200105)26:4<461:AIOPP2>2.0.ZU;2-8
Abstract
Two related protein phosphatases 2C, ABI1 and AtPP2CA have been implicated as negative regulators of ABA signalling. In this study we characterized th e role of AtPP2CA in cold acclimation. The pattern of expression of AtPP2CA and ABI1 was studied in different tissues and in response to abiotic stres ses. The expression of both AtPP2CA and ABI1 was induced by low temperature , drought, high salt and ABA. The cold and drought-induced expression of th ese genes was ABA-dependent, but divergent in various ABA signalling mutant s. In addition, the two PP2C genes exhibited differences in their tissue-sp ecific expression as well as in temporal induction in response to low tempe rature. To elucidate the function of AtPP2CA in cold acclimation further, t he corresponding gene was silenced by antisense inhibition. Transgenic anti sense plants exhibited clearly accelerated development of freezing toleranc e. Both exposure to low temperature and application of ABA resulted in enha nced freezing tolerance in antisense plants. These plants displayed increas ed sensitivity to ABA both during development of frost tolerance and during seed germination, but not in their drought responses. Furthermore, the exp ression of cold-and ABA-induced genes was enhanced in transgenic antisense plants. Our results suggest that AtPP2CA is a negative regulator of ABA res ponses during cold acclimation.