Influence of sucrose starvation, osmotic and salt stresses on expression profiles of genes involved in the development of autophagy by means of microtubules
Aim. The aim of this work was to investigate changes in expression profiles of key genes involved in the development of autophagy by means of microtubules under the influence of sucrose starvation, osmotic and salt stresses. Methods. Arabidopsis thaliana seeds were sown aseptically on Murashige and Skoog solid medium. Salt and osmotic stresses were simulated by seed germination and seedlings cultivation on the media containing 150 mМ NaCl and 10 mМ mannitol, respectively. For investigation of starvation-induced autophagy plants were germinated and grown on sucrose-free medium. Results. Changes in expression of α-tubulin and atg8 genes had clearly defined stressdependent nature. Overexpression of tua1 and atg8e under starvation; tua3 and atg8f under osmotic stress; tua3 and atg8f, atg8e during salt stress indirectly testifies interaction between the structural units of autophagosomes and microtubules. It was shown that influence of investigated abiotic stimuli results in overexpression of elp3 and hda6 genes. Small increase in expression levels of hexokinase 2 and 3 was demonstrated. Conclusions. Transcriptome analysis of key genes involved in realization of autophagy induced by sucrose starvation, osmotic and salt stresses in Arabidopsis thaliana cells was conducted. Received data indirectly testifies interaction between the structural units of autophagosomes and microtubules and enables to point α-tubulin and atg8 genes, which are specific for the realization of autophagy induced by a certain abiotic stimuli. Expression profiles of elp3/deacetylases as well as hexokinases indicate the critical role of α-tubulin acetylation for autophagic response, that is involved in the development of programmed cell death.
Keywords: autophagy, sucrose starvation, osmotic stress, salt stress, transcriptome analysis, α-tubulin, atg8.
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