# The ABAP1 interacting protein 10 (AIP10) exerts a dual role in the cell cycle and primary metabolism pathways in Arabidopsis thaliana

## TL;DR

AIP10 in Arabidopsis connects cell division and metabolism, and its absence boosts plant growth and productivity by increasing cell division and carbon fixation.

## Contribution

AIP10 is identified as a novel regulatory hub linking the cell cycle and primary metabolism in plants.

## Key findings

- AIP10 knockout increases cell division rates and biomass production.
- AIP10 silencing enhances photosynthetic efficiency and carbon fixation.
- AIP10 interacts with ABAP1 and KIN10 to modulate plant development and metabolism.

## Abstract

Plants have developed a sophisticated regulatory network that coordinates gene expression in meristematic zones in response to environmental conditions. Here, we identified a protein in Arabidopsis (Arabidopsis thaliana) that interacts with Armadillo BTB Arabidopsis protein 1 (ABAP1), a negative regulator of the cell cycle in plants. We characterized the ABAP1 interacting protein (named AIP10) investigating its role in modulating plant development. T‐DNA insertion lines with silenced expression of AIP10 were evaluated phenotypically (morphology, fresh and dry weight), via transcriptomics analyses (RNA‐Seq and RT‐qPCR), physiologically (biochemically, Fluorcam and Li‐COR) and metabolically (ATR‐FTIR). We showed that AIP10 integrates cell division rates with transcriptional and primary metabolism reprogramming through its protein interactions with ABAP1 and KIN10, a subunit of SnRK1 (sucrose non‐fermenting‐1‐related protein kinase 1). ABAP1 levels and activity were reduced in the absence of AIP10, licensing cell cycle progression for longer periods, which culminated in increased rates of cell division that boosted vegetative and reproductive growth. AIP10 knockout triggered a major transcriptional reprogramming of plant primary metabolism, possibly through SnRK1 modulation. aip10 mutants showed increased photosynthetic efficiency, as well as boosted carbon fixation, leading to increased biomass, seed productivity, and higher contents of proteins, lipids (triglycerides), and carbohydrates. Finally, we propose that the modulation of AIP10 expression is part of a mechanism that coordinates higher rates of cell division with better photosynthetic performance and carbon fixation to metabolically meet the plant energy demand, allowing the generation of plants with increased biomass and productivity.

Plants regulate cell division to adapt growth to environmental changes. In Arabidopsis thaliana, AIP10 acts as a hub linking the cell cycle to primary metabolism. Its silencing increases cell division rates, enhances carbon fixation, and boosts metabolite accumulation, driving improved development and productivity.