Effect of simulated microgravity on gene expression during embryogenesis of Arabidopsis thaliana

Abstract

Gravitational force is one of environmental factors that influence growth and development of plants. Changes in this force, including microgravity, can be one of the stress factor which plants have to adapt to cope with. That kind of stress can lead to several abnormalities such as chromosomal breakage, morphological abnormalities or changes in gene expression. The aim of this study was to examine the influence of simulated microgravity on gene expression of Arabidopsis thaliana embryos by use Random Positioning Machine (RPM). RPM is laboratory facility that can generate conditions comparable to the true microgravity. This paper studies effect of simulated microgravity on expression of genes which are involved in plant embryogenesis (LEAFY COTYLEDON, LATE EMBRYOGENESIS ABUNDANT), antioxidative system (CATALASE), mechanical stimuli (TOUCH) and gravitropism (SCARECROW, SHOOT GRAVITROPISM2). Changes in gene expression were detected using quantitative real-time PCR (qRT-PCR). Several of tested genes had increased transcript levels after the influence of simulated microgravity. Specifically, catalase (CAT3), LECs (LEC1), touch (TCH2/CML24), and gravitropism (SGR2) genes achieved significantly increased relative expression (level [≥] 2). The changes in the levels of expression on embryos of Arabidopsis depend on the type of genes and principally on the timing of the influence of the simulated microgravity.