The chemical compound ‘Heatin’ stimulates hypocotyl elongation and interferes with the Arabidopsis NIT1-subfamily of nitrilases

0549885 - ÚEB 2022 RIV GB eng J - Journal Article
van der Woude, A. - Piotrowski, M. - Klaasse, G. - Paulus, J. K. - Krahn, D. - Ninck, S. - Kaschani, F. - Kaiser, M. - Novák, Ondřej - Ljung, K. - Bulder, S. - Van Verk, M. C. - Snoek, L. B. - Fiers, M. - Martin, N. I. - van der Hoorn, R. A.L. - Robert, S. - Smeekens, S. - van Zanten, M.
The chemical compound ‘Heatin’ stimulates hypocotyl elongation and interferes with the Arabidopsis NIT1-subfamily of nitrilases.
Plant Journal. Roč. 106, č. 6 (2021), s. 1523-1540. ISSN 0960-7412. E-ISSN 1365-313X
R&D Projects: GA MŠMT(CZ) EF16_019/0000827
Institutional support: RVO:61389030
Keywords : 1-iminomethyl-2-naphthol * aldehyde oxidase * Arabidopsis * chemical genetics * Heatin * ian * indole-3-acetonitrile * NIT1-subfamily * nitrilases * pif4 * thermomorphogenesis
OECD category: Biochemistry and molecular biology
Impact factor: 7.091, year: 2021
Method of publishing: Open access
http://doi.org/10.1111/tpj.15250

Temperature passively affects biological processes involved in plant growth. Therefore, it is challenging to study the dedicated temperature signalling pathways that orchestrate thermomorphogenesis, a suite of elongation growth-based adaptations that enhance leaf-cooling capacity. We screened a chemical library for compounds that restored hypocotyl elongation in the pif4-2–deficient mutant background at warm temperature conditions in Arabidopsis thaliana to identify modulators of thermomorphogenesis. The small aromatic compound ‘Heatin’, containing 1-iminomethyl-2-naphthol as a pharmacophore, was selected as an enhancer of elongation growth. We show that ARABIDOPSIS ALDEHYDE OXIDASES redundantly contribute to Heatin-mediated hypocotyl elongation. Following a chemical proteomics approach, the members of the NITRILASE1-subfamily of auxin biosynthesis enzymes were identified among the molecular targets of Heatin. Our data reveal that nitrilases are involved in promotion of hypocotyl elongation in response to high temperature and Heatin-mediated hypocotyl elongation requires the NITRILASE1-subfamily members, NIT1 and NIT2. Heatin inhibits NIT1-subfamily enzymatic activity in vitro and the application of Heatin accordingly results in the accumulation of NIT1-subfamily substrate indole-3-acetonitrile in vivo. However, levels of the NIT1-subfamily product, bioactive auxin (indole-3-acetic acid), were also significantly increased. It is likely that the stimulation of hypocotyl elongation by Heatin might be independent of its observed interaction with NITRILASE1-subfamily members. However, nitrilases may contribute to the Heatin response by stimulating indole-3-acetic acid biosynthesis in an indirect way. Heatin and its functional analogues present novel chemical entities for studying auxin biology.
Permanent Link: http://hdl.handle.net/11104/0325776