TY - JOUR
T1 - Autophagy mediates hydrotropic response in Arabidopsis thaliana roots
AU - Jiménez-Nopala, Gladys
AU - Salgado-Escobar, Angel Eduardo
AU - Cevallos-Porta, Diego
AU - Cárdenas, Luis
AU - Sepúlveda-Jiménez, Gabriela
AU - Cassab, Gladys
AU - Porta, Helena
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/7
Y1 - 2018/7
N2 - This work shows that autophagy plays a key role in the hydrotropic curvature of Arabidopsis thaliana roots. An analysis of GFP-ATG8a transgenic plants showed that autophagosomes accumulated in the root curvature 2 h after the transfer of seedlings to Normal Medium-Water Stress Medium (NM-WSM). Autophagy flux was required for root bending. Remarkably, several atg mutants did not show hydrotropic curvature in NM-WSM or the splitting-agar system. Hyper, an H2O2 sensor showed that H2O2 preferentially accumulated in the root curvature at a similar rate as the autophagosomes did during hydrotropic response. Peroxidase and ROBH activity inhibition affected, negatively or positively root curvature. This data suggested H2O2 balance was required for root bending. Malondialdehyde, a metabolite used as an indicator of oxidative stress, accumulated at the same rate during the development of the curvature in NM-WSM. These results suggest that autophagy is required for the hydrotropic response in NM-WSM. We discuss the possible regulatory role of H2O2 on autophagy during the hydrotropic response that might relieve oxidative stress provoked by water stress. NM-WSM is water stress system suitable for studying hydrotropic responses on a short-term basis.
AB - This work shows that autophagy plays a key role in the hydrotropic curvature of Arabidopsis thaliana roots. An analysis of GFP-ATG8a transgenic plants showed that autophagosomes accumulated in the root curvature 2 h after the transfer of seedlings to Normal Medium-Water Stress Medium (NM-WSM). Autophagy flux was required for root bending. Remarkably, several atg mutants did not show hydrotropic curvature in NM-WSM or the splitting-agar system. Hyper, an H2O2 sensor showed that H2O2 preferentially accumulated in the root curvature at a similar rate as the autophagosomes did during hydrotropic response. Peroxidase and ROBH activity inhibition affected, negatively or positively root curvature. This data suggested H2O2 balance was required for root bending. Malondialdehyde, a metabolite used as an indicator of oxidative stress, accumulated at the same rate during the development of the curvature in NM-WSM. These results suggest that autophagy is required for the hydrotropic response in NM-WSM. We discuss the possible regulatory role of H2O2 on autophagy during the hydrotropic response that might relieve oxidative stress provoked by water stress. NM-WSM is water stress system suitable for studying hydrotropic responses on a short-term basis.
KW - Autophagy
KW - HO accumulation
KW - Lipid peroxidation
KW - Root hydrotropism
KW - Water potential gradient
UR - http://www.scopus.com/inward/record.url?scp=85045005618&partnerID=8YFLogxK
U2 - 10.1016/j.plantsci.2018.03.026
DO - 10.1016/j.plantsci.2018.03.026
M3 - Artículo
C2 - 29807580
SN - 0168-9452
VL - 272
SP - 1
EP - 13
JO - Plant Science
JF - Plant Science
ER -