The 30th International Conference on Arabidopsis Research (ICAR 2019)

648 / 2019-05-12 17:51:15

Dorsoventral boundaries in leaf development

leaf,boundaries,REVOLUTA,KANADI,morphogenesis,auxin,polarity,dorsoventral,adaxial,abaxial

Plenary track > Development

A fundamental question in plant development is how cell polarity and morphogenesis are regulated. Recently we found that cell polarity is oriented by localized auxin induced transcriptional activity and that this activity is restricted by the Class III HD-ZIP and KANADI transcription factors to narrow regions of cells between their expression domains, as found in the meristem peripheral zone and along leaf margins. According to established dogma however, direct juxtaposition of dorsal and ventral cell types should provoke organogenesis, without necessarily requiring a zone of separation or “middle domain” between these two cell types. To investigate this conundrum we have used live imaging to observe the consequences of direct juxtaposition of HD-ZIPIII and KAN expression in the ventral and dorsal cells of leaf primordia respectively. Our results reveal novel cell-cell signalling functions for REV that start to provide a new understanding for how plant dorsal-ventral boundaries are established and how they regulate morphogenesis.