a 2009

Effects of magnesium binding and beryllofluoridation on a component of the cytokinin signaling pathway studied by nuclear magnetic resonance

TŘÍSKOVÁ, Olga, Blanka PEKÁROVÁ, Veronika MOTÁČKOVÁ, Lukáš ŽÍDEK, Vladimír SKLENÁŘ et. al.

Basic information

Original name

Effects of magnesium binding and beryllofluoridation on a component of the cytokinin signaling pathway studied by nuclear magnetic resonance

Name in Czech

Účinek navázání Mg(2+) a BeF3 na část cytokininové dráhy studované pomocí nukleární magnetické rezonance

Name (in English)

Effects of magnesium binding and beryllofluoridation on a component of the cytokinin signaling pathway studied by nuclear magnetic resonance

Authors

Edition

2009

Other information

Type of outcome

Konferenční abstrakt

Confidentiality degree

není předmětem státního či obchodního tajemství

Organization unit

Faculty of Science
Změněno: 9/4/2010 15:19, RNDr. Lubomír Janda, Ph.D.

Abstract

V originále

Cytokinins are important regulators of intrinsic developmental programs leading to de- and re-differentiation of plant cells. The cytokinin signal transduction seems to be mediated via multistep phospohorylation, similar to the action of bacterial two-component signalling systems. A soluble receiver domain of CKI1 receptor histidine kinase of Arabidopsis thaliana has been investigated by nuclear magnetic resonance (NMR) in this study. The domain was expressed in E. coli and labeled with stable isotopes (13)C, (15)N. Resonance frequencies have been assigned using standard strategy and conformational changes were monitored by running 2D (1)H-(15)N HSQC spectra. Effect of Mg(2+) has been studied in a series of titration experiments and the most significantly affected residues were identified using secondary chemical shift mapping. Activation of the protein, which cannot be studied in real time due to a short life-time of the activated form with phosphorylated aspartate, was investigated in an artificial system with phosphate replaced by beryllofluoride. In both cases, the observed chemical shift changes were mapped on a recently solved X-ray structure of the non-phosphorylated protein. In addition to the structural studies, molecular motions were investigated by N-15 NMR relaxation experiments. Series of relaxation spectra were obtained for free, Mg(2+)-bound, and beryllofluorinated protein and interpreted in terms of the Lipari-Szabo model-free approach. The observed changes are discussed in context of the X-ray structure of the free protein.

Links

MSM0021622415, plan (intention)
Name: Molekulární podstata buněčných a tkáňových regulací
Investor: Ministry of Education, Youth and Sports of the CR, Molecular basis of cell and tissue regulations