Identification of new adventitious rooting mutants amongst suppressors of the Arabidopsis thaliana superroot2 mutation

Daniel Ioan Pacurar (1, 2) , Monica Lacramioara Pacurar (1, 3) , John Desmond Bussell (4, 5) , Joseli Schwambach (6, 3) , Tiberia Ioana Pop (1, 2) , Mariusz Kowalczyk (3) , Laurent Gutierrez (7, 3) , Emilie Cavel (2) , Salma Chaabouni (2) , Karin Ljung (3) , Arthur Germano Fett-Neto (6) , Doru Pamfil (1) , Catherine Bellini (8, 9)

1 University of Agricultural Sciences and Veterinary Medicine
2 Dept Plant Physiol
3 Dept Forest Genet & Plant Physiol
4 UWA - The University of Western Australia
5 Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol
6 Lab Fisiol Vegetal, Ctr Biotecnol
7 BIOPI - Biologie des Plantes et Innovation - UR UPJV 3900
8 IJPB - Institut Jean-Pierre Bourgin
9 Department of Plant Physiology

Auxin is a major regulator of adventitious rooting and, to better understand its role, we identified suppressor mutants of superroot2-1. This provides new resources for the discovery of genetic players involved in auxin signalling or auxin crosstalk with other hormones.The plant hormone auxin plays a central role in adventitious rooting and is routinely used with many economically important, vegetatively propagated plant species to promote adventitious root initiation and development on cuttings. Nevertheless the molecular mechanisms through which it acts are only starting to emerge. The Arabidopsis superroot2-1 (sur2-1) mutant overproduces auxin and, as a consequence, develops excessive adventitious roots in the hypocotyl. In order to increase the knowledge of adventitious rooting and of auxin signalling pathways and crosstalk, this study performed a screen for suppressors of superroot2-1 phenotype. These suppressors provide a new resource for discovery of genetic players involved in auxin signalling pathways or at the crosstalk of auxin and other hormones or environmental signals. This study reports the identification and characterization of 26 sur2-1 suppressor mutants, several of which were identified as mutations in candidate genes involved in either auxin biosynthesis or signalling. In addition to confirming the role of auxin as a central regulator of adventitious rooting, superroot2 suppressors indicated possible crosstalk with ethylene signalling in this process.

Mots clés: Adventitious roots; Arabidopsis; auxin; ethylene; superroot; suppressors; AUXIN RESPONSE FACTOR; REGULATED GENE-EXPRESSION; ARABIDOPSIS-THALIANA; NITRIC-OXIDE; ETHYLENE BIOSYNTHESIS; RECESSIVE MUTATION; PROTEIN RUB1; PATHWAY; HOMEOSTASIS; CUTTINGS

Domaines: Biologie végétale

Daniel Ioan Pacurar, Monica Lacramioara Pacurar, John Desmond Bussell, Joseli Schwambach, Tiberia Ioana Pop, et al.. Identification of new adventitious rooting mutants amongst suppressors of the Arabidopsis thaliana superroot2 mutation. Journal of Experimental Botany, 2014, 65 (6), pp.1605 - 1618. ⟨10.1093/jxb/eru026⟩. ⟨hal-01204017⟩