Nitric oxide modulates actin filament organization in Arabidopsis thaliana primary root cells at low temperatures.

Cytoskeleton is gaining the increasing recognition as one of nitric oxide (NO)-downstream targets because of its involvement in plenty of NO-controlled processes in plants throughout the entire life cycle starting from seed germination to pollination as well as (a)biotic stress tolerance. It has been revealed that low temperature (+0.5°C) has an inhibitory effect on A. thaliana primary root growth and causes an anisotropic increase of epidermal cells diameter in elongation zone. Furthermore, actin filaments' organization of epidermal cells in different zones of primary roots is modulated by NO content. Thus, the exogenous NO donor (SNP) favors to actin filaments network reorganization, while both cold and NO scavenger (c-PTIO) increase its randomization. According to the data obtained, it can be assumed that not only actin filaments act as NO sensors, but NO is also involved into plant cell response on low temperatures by the signaling via such important cytoskeleton machinery as actin network.