New preprint!

How an in house collaboration makes you look at your pet system differently and takes you out of your comfort zone. With the lab of E. Gaquerel we asked: how does Arabidopsis match the formation of lateral root with the metabolic resources required?

Mutants that do not form lateral root (LR) are replete with non-consumed carbohydrates in leaves. Metabolomics shows that LR formation is linked to a glycolytic switch close to the metabolic reprogramming observed upon acquisition of pluripotency in animals.

This glycolytic switch is auxin triggered, essential for LR formation and activates the TOR complex in the pericycle. Ubiquitous or pericycle specific TOR mutants or chemical inhibition converge on a clear message: TOR is essential for lateral root to initiate.

Curiously, knocking down or inhibiting TOR does not alter the transcriptome response of the pericycle to auxin but alters the translatome. TOR modulates the translation of many auxin induced mRNAs esp. ARF7, ARF19 and LBD16.

TOR thus acts as a gatekeeper for post-embryonic LR formation. It integrates local auxin-dependent pathways with systemic metabolic signals, modulating the translation of auxin induced gene expression.