Genetic Robustness Control of Auxin Output in Priming Organ Initiation
Published:13 Jul.2023 Source:PNAS
In plants, MP (MONOPTEROS)-mediated auxin signaling is essential for organ initiation. We suggest a molecular framework for auxin in the robustness control of organ initiation in the meristem.
We demonstrate that MP interacts with DRNL (DORNROSCHEN-LIKE) to trigger organ initiation by limiting cytokinin accumulation and activating AINTEGUMENTA, AINTEGUMENTA-LIKE6, TARGET OF MONOPTEROS 3, and FILAMENTOUS FLOWERS expression. Although DRNL and its paralog DRN are not coexpressed, they act redundantly during organ initiation.
We show that in drnl mutants, DRN transcripts are ectopically activated in organ initiation sites to compensate for the functional deficiency of drnl in organ initiation. Our work suggests that a spatial gene compensation–based safety strategy in auxin signaling participates to the genetic robustness control of organ initiation.