The ROP2 GTPase Participates in Nitric Oxide (NO)-Induced Root Shortening in Arabidopsis

Kenesi, Erzsébet and Kolbert, Zsuzsanna and Kaszler, Nikolett and Klement, Éva and Ménesi, Dalma and Molnár, Árpád and Valkai, Ildiko and Feigl, Gábor and Rigó, Gábor and Cséplő, Ágnes and Fehér, Attila (2023) The ROP2 GTPase Participates in Nitric Oxide (NO)-Induced Root Shortening in Arabidopsis. PLANTS, 12 (4). ISSN 2223-7747

Preview

Text plants-12-00750-v2.pdf Download (3MB) | Preview

Abstract

Nitric oxide (NO) is a versatile signal molecule that mediates environmental and hormonal signals orchestrating plant development. NO may act via reversible S-nitrosation of proteins during which an NO moiety is added to a cysteine thiol to form an S-nitrosothiol. In plants, several proteins implicated in hormonal signaling have been reported to undergo S-nitrosation. Here, we report that the Arabidopsis ROP2 GTPase is a further potential target of NO-mediated regulation. The ROP2 GTPase was found to be required for the root shortening effect of NO. NO inhibits primary root growth by altering the abundance and distribution of the PIN1 auxin efflux carrier protein and lowering the accumulation of auxin in the root meristem. In rop2-1 insertion mutants, however, wild-type-like root size of the NO-treated roots were maintained in agreement with wild-type-like PIN1 abundance in the meristem. The ROP2 GTPase was shown to be S-nitrosated in vitro, suggesting that NO might directly regulate the GTPase. The potential mechanisms of NO-mediated ROP2 GTPase regulation and ROP2-mediated NO signaling in the primary root meristem are discussed.

Actions (login required)

Edit Item