sentence: Heterodimer formed by AtbHLH156 / LHW in subfamily XIII and AtbHLH032 / TOM5 or AtbHLH030 / T5 L1 or SACLs ( AtbHLH142 – 145 ) coupling with auxin and cytokinin signaling pathways participates in the regulation of Arabidopsis root vascular initial population [ 56 ] .