# Flowering in Space: Transcriptional Insights Into the Crosstalk Between Aging, Gibberellin, and Sugar Pathways to Modulate Flowering in Space

## TL;DR

This paper explores how spaceflight affects plant flowering through hormonal and genetic pathways, focusing on Arabidopsis grown on the International Space Station.

## Contribution

The study identifies SPL transcription factors as a central hub in spaceflight-induced flowering and reveals how space conditions reprogram plant developmental networks.

## Key findings

- Spaceflight conditions modulate flowering through hormonal and genetic pathways involving gibberellin and sugar signaling.
- Elevated gibberellin biosynthesis genes and altered sugar signaling contribute to the activation of SPLs and floral transition.
- SPLs act as a central regulatory hub, suppressing floral repressors and inducing integrator genes like AGL24.

## Abstract

Spaceflight presents a unique environment that affects plant development, including flowering time. Using transcriptomic data of Arabidopsis seedlings grown aboard the International Space Station, we found that spaceflight conditions modulate flowering through coordinated hormonal and genetic pathways. Elevated expression of gibberellin biosynthesis genes suggests increased GAs accumulation, which likely promote SPL transcription factor expression and activity by degrading DELLA repressors, while altered sugar signaling represses miR156, contributing to the upregulation of SPLs. This cascade activates miR172, suppressing floral repressors and inducing integrator genes such as AGL24, ultimately triggering floral transition. Our findings identify SPLs as a central regulatory hub in spaceflight‐induced flowering and reveal how space conditions reprogram developmental signaling networks. Our findings can be important for advancing our understanding of plant adaptation beyond Earth and support the development of controlled flowering strategies in extraterrestrial agriculture. This work contributes to the broader goal of creating sustainable bioregenerative life support systems for long‐duration space missions.