ZLL/AGO10 maintains shoot meristem stem cells during Arabidopsis embryogenesis by down-regulating ARF2-mediated auxin response
10.09.2015 Roodbarkelari F, Du F, Truernit E, Laux T. BMC Biol. 2015 Sep 10;13:74. We addressed whether stem cell maintenance by ZWILLE (ZLL) involves regulation of auxin. In zll-1 mutants, expression of the auxin response reporter DR5:GFP is elevated, and transcription of the AUXIN RESPONSE FACTOR 2 (ARF2) gene is upregulated. Downregulation of ARF2 significantly restores stem cells in zll-1 mutants, whereas increased expression of ARF2 enhances differentiation. Upregulation of the ZLL effector gene REVOLUTA restores ARF2 expression and stem cell maintenance in zll-1 embryos. 