Cytokinins (CKs) are phytohormones regulating plant growth and development as well as response to the environment. In order to evaluate their function in heat stress (HS) responses, the effect of CK elevation was determined during three types of HS - targeted to shoots, targeted to roots and applied to the whole plant. The early (30min) and longer term (3h) responses were followed at the hormonal, transcriptomic and proteomic levels in Arabidopsis transformants with dexamethasone-inducible expression of the CK biosynthetic gene isopentenyltransferase (ipt) and the corresponding wild-type (Col-0). Combination of hormonal and phenotypic analyses showed transient up-regulation of the CK/abscisic acid ratio, which controls stomatal aperture, to be more pronounced in the transformant. HS responses of the root proteome and Rubisco-immunodepleted leaf proteome were followed using 2-D gel electrophoresis and MALDI-TOF/TOF. More than 100 HS-responsive proteins were detected, most of them being modulated by CK increase. Proteome and transcriptome analyses demonstrated that CKs have longer term positive effects on the stress-related proteins and transcripts, as well as on the photosynthesis-related ones. Transient accumulation of CKs and stimulation of their signal transduction in tissue(s) not exposed to HS indicate that they are involved in plant stress responses.

• MeSH
• alkyltransferasy a aryltransferasy fyziologie   MeSH
• Arabidopsis účinky léků   metabolismus   fyziologie   MeSH
• cytokininy fyziologie   MeSH
• dexamethason farmakologie   MeSH
• kořeny rostlin metabolismus   fyziologie   MeSH
• kyselina abscisová fyziologie   MeSH
• proteomika MeSH
• reakce na tepelný šok fyziologie   MeSH
• regulace genové exprese u rostlin fyziologie   MeSH
• regulátory růstu rostlin fyziologie   MeSH
• signální transdukce účinky léků   fyziologie   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• stanovení celkové genové exprese MeSH
• výhonky rostlin metabolismus   fyziologie   MeSH
• vysoká teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH