To investigate the interplay between Cortical Microtubules (CMT) and Reactive Oxygen Species (ROS) during vascular regeneration in leaf

Abstract

Aerial organs of the plants are susceptible to numerous local wounds throughout their lifespan, owing to their static lifestyle. They are subjected to both biotic and abiotic factors. Regenerative responses to wounds can range from local healing by cell proliferation to total tissue or organ regeneration. The role of auxin in vascular regeneration in growing leaves and stems has been known for a long time. Ongoing research in the lab has shown the significance of Cortical MicroTubule (CMT) and Reactive Oxygen Species (ROS) in leaf vascular regeneration. However, knowledge of the interaction between CMT and ROS is still elusive. To understand genetic interaction between CMT and ROS, we generated double mutants deficient in either ROS (rbohDrbohF) or in both CMT and ROS (rbohDclasp and rbohFclasp). We found that double mutant deficient in both CMT and ROS, rbohFclasp did not show any defect in vascular regeneration efficiency but did show a straight path of reunion in some of the regenerated samples. This double mutant phenocopies ROS single mutant, rbohF indicating that rbohF is epistatic to clasp. Furthermore, rbohF was also found to be epistatic to rbohD since vascular regeneration in rbohDrbohF phenocopies rbohF. Additionally, we found that CMT and auxin response in rbohD was similar to wild type. Further experiments to investigate the changes in CMT dynamics and auxin in ROS double mutant, rbohDrbohF are underway. Although, rbohDrbohF did not show any defect in vascular regeneration but some of the regenerated samples showed a straight path of reunion. This study sheds light on the genetics and cellular interactions between CMT and ROS, indicating their importance during vascular regeneration in leaves. Recent data suggests that CMT plays an important role in influencing vascular regeneration efficiency and ROS seems to be involved in guiding the path of reunion between physically disconnected vascular strands. Deeper insights into vascular regeneration in plants will pave the way towards improving crop plants resilience and regenerative capacity.