lt; 0.05) at both the proteomic and transcriptomic levels are in the minority. Most differentially expressed genes were found to be regulated at either the proteomic or the transcriptomic level, but not both. Despite this, our data show a strong correlation—greater than 0.7—between proteomic and transcriptomic changes. We also demonstrated that a few peptides were detected at the proteomic level, supporting the conclusion that alternative splicing has a measurable impact on protein abundance. The Gene Ontology terms enriched after heat treatment were similar at both transcriptomic and proteomic levels, including terms such as heat stress response and heat stress tolerance. However, the terms enriched among alternatively spliced genes were distinct and did not include heat stress response or tolerance. This suggests that alternative splicing and heat stress are both important for the heat stress 105 response but affect different sets of genes involved in plant growth and development. Furthermore, we observed that even a small developmental difference—just 24 hours between the two stages—resulted in significant variation in differentially expressed and spliced genes. This indicates that the heat stress response differs notably between these two developmental stages in the seed.