Inactivation of the entire Arabidopsis group II GH3s confers tolerance to salinity and water deficit

0562422 - ÚEB 2023 RIV GB eng J - Journal Article
Casanova-Sáez, R. - Mateo-Bonmatí, E. - Šimura, J. - Pěnčík, Aleš - Novák, Ondřej - Staswick, P. - Ljung, K.
Inactivation of the entire Arabidopsis group II GH3s confers tolerance to salinity and water deficit.
New Phytologist. Roč. 235, č. 1 (2022), s. 263-275. ISSN 0028-646X. E-ISSN 1469-8137
R&D Projects: GA MŠMT(CZ) EF16_019/0000827
Institutional support: RVO:61389030
Keywords : Arabidopsis * auxin * drought * gh3 * salinity * stress tolerance
OECD category: Biochemistry and molecular biology
Impact factor: 9.4, year: 2022
Method of publishing: Open access
https://doi.org/10.1111/nph.18114

Indole-3-acetic acid (IAA) controls a plethora of developmental processes. Thus, regulation of its concentration is of great relevance for plant performance. Cellular IAA concentration depends on its transport, biosynthesis and the various pathways for IAA inactivation, including oxidation and conjugation. Group II members of the GRETCHEN HAGEN 3 (GH3) gene family code for acyl acid amido synthetases catalysing the conjugation of IAA to amino acids. However, the high degree of functional redundancy among them has hampered thorough analysis of their roles in plant development. In this work, we generated an Arabidopsis gh3.1,2,3,4,5,6,9,17 (gh3oct) mutant to knock out the group II GH3 pathway. The gh3oct plants had an elaborated root architecture, showed an increased tolerance to different osmotic stresses, including an IAA-dependent tolerance to salinity, and were more tolerant to water deficit. Indole-3-acetic acid metabolite quantification in gh3oct plants suggested the existence of additional GH3-like enzymes in IAA metabolism. Moreover, our data suggested that 2-oxindole-3-acetic acid production depends, at least in part, on the GH3 pathway. Targeted stress-hormone analysis further suggested involvement of abscisic acid in the differential response to salinity of gh3oct plants. Taken together, our data provide new insights into the roles of group II GH3s in IAA metabolism and hormone-regulated plant development.
Permanent Link: https://hdl.handle.net/11104/0334738