A Tyrosine Kinase-Like Gene BdCTR1 Negatively Regulates Flowering Time in the Model Grass Plant Brachypodium distachyon

Flowering time is critical for the regional adaptation, yield, and reproduction of crop plants. Tyrosine kinase-like (TKL) genes are protein kinases (PKs) that play important roles in various plant processes. However, the functions of only a few TKLs in controlling flowering time in plants have been characterized. As a genetic model system, Brachypodium distachyon has been widely used in the study of gramineous crop species. Here, we identified and characterized the function of the model plant Brachypodium (poaceae) tyrosine kinase-like kinase BdCTR1 in controlling flowering time. BdCTR1 mutation caused earlier flowering compared with wild-type (WT) plants. Transcriptomic analysis revealed 2261 differentially expressed genes (DEGs) related to the circadian rhythm, phytohormone signaling, and flavonoid biosynthesis pathways in Bdctr1 mutants compared with the wild type (WT). Quantitative reverse transcription–polymerase chain reaction (qRT–PCR) revealed that the expression levels of flowering-related genes, including FT, PPD1, CO, and FUL, and ET-related genes, including ETR, MKK, and ERF, were altered in Bdctr1 mutants compared with those in WT plants. Thus, our results show that BdCTR1 plays a role in controlling flowering time by regulating various signaling pathways and contribute to elucidating the molecular mechanisms of PKs in controlling plant flowering.