Molecular networks orchestrating plant cell growth

•Multi-layered gene regulatory networks (GRNs) control cell growth.•Protein phosphorylation, degradation, and antagonistic interactions modulate GRNs.•A GRN consisting of BAP/D and HLH/bHLH modules control cell growth in hypocotyls.•A GRN consisting of RSL/LRL module governs root hair growth.•BAP/D and RSL/LRL integrate environmental stimuli to adjust cell growth.

Plant cell growth can broadly be categorized into either diffuse or tip growth. Here we compare gene regulatory networks (GRNs) controlling growth of hypocotyls and root hairs as examples for diffuse and tip growth, respectively. Accumulating evidence shows that GRNs in both cell types are multi-layered in structure and fine-tuned by transcriptional and post-translational mechanisms. We discuss how these GRNs regulate the expression of proteins controlling cell wall remodeling or other growth regulatory processes. Finally, we highlight how specific regulators within GRNs adjust plant cell growth in response to variable environmental conditions.