RNAseq of 4 day old etiolated Arabidopsis thaliana Ler and gin2-1 seedlings grown in darkness at 18C

Post-germination, emerging seedlings rely on storage reserves to fuel cellular metabolism until photoautotrophic growth is established. Seed reserves can also sustain growth when seedlings are occluded from light, by for instance, soil or debris, which delays the switch to photosynthesis-driven growth. This study has shown that HEXOKINASE 1 (HXK1) supports early seedling growth, particularly during periods of prolonged darkness or low light. HXK1 is an evolutionarily conserved enzyme that catalyzes the first glycolytic step in cellular respiration for energy production. We show that HXK1 also has a broader function in nutrient resource management, balancing the transcriptional control of energy generating vs demanding processes with the seedling internal carbon status.