BCAA catabolic mutants in prolonged darkness

We used RNA-Seq to ask whether the transcripts for the proposed BCKDH subunits are upregulated in wild-type plants subjected to prolonged darkness. These experiments were performed using rosette leaves from 5-week-old, short-day-grown (8h light/16h dark) Col-0 wild-type plants moved to constant darkness for 6h, 24h, 48h and 72h, and grown in short day for 72h as control. The transcripts of eight BCAA catabolism genes were increased nine- to 400-fold within the first 6h of prolonged darkness, and remained high until the last time point. These results are consistent with the hypothesis that BCAA catabolic enzymes - including BCKDH subunits E1A1, E1B1, E1B2 and E2 - have one or more physiological roles in the dark. Overall design: Rosette leaf mRNA profiles of 5-week old Col wild type (WT, CS60000) and BCAA catabolic mutants ivd1-2 and hml1-2 were generated byRNA sequencing, in duplicate, using Illumina HiSeq2500.