Actions of strigolactone GR24 and DRM1 gene expression on Arabidopsis root architecture

Strigolactones are mostly known for their influence on apical dominance, but new insights suggest that they may be involved in many other biological events including root development. DRM1 gene is ubiquitary expressed in plants but its role is not well known. In our experiments, the strigolactone analogue GR24 stimulated the expression of DRM1.1, DRM1.2, DRM1.4 splicing variants and inhibited root branching in 5-day-old Arabidopsis thaliana (L.) Heynh. seedlings. On the other hand, the expression of these splicing variants was lower in 10-day-old GR24-treated roots. DRM1.6 gene expression differently responded to GR24 than other DRM1 splicing variants, however, there was no clear relationship between DRM1.6 expression and root length. Our results suggest that strigolactones and the expression of DRM1 gene play interactive roles in root branching.