S04 - Session P4 - Monitoring adventitious shoot meristem initiation on arabidopsis root explants by means of stem cell reporters

Authors: Elnara Sadigova *, Stefaan Werbrouck

Stem cells form the core of apical shoot meristems and possess mechanisms to balance the number of cell divisions. Their initiation on explants is very important for plant biotechnology as they are required for gene transformation, gene editing or mutagenesis methods. Auxin and cytokinins influence the STM and WUS-CLV signaling systems that control stem cell regeneration. This experiment visualizes their effect on adventitious shoot regeneration on isolated A. thaliana root explants carrying reporter genes such as pSTM::GFP, pCLV::GFP and CUC::YFP. The advantage of this method is the very early visualization of meristem formation which in principle allows early intervention if things go wrong. Different combinations of aromatic and isoprenoid cytokinins with auxins were tested. STM and CUC had very early and clear expression in contrast to CLV. In contrast to MemTR, mTR was better than the classically used 2ip. The presence of auxins, such as IAA, was crucial to obtain sufficient shoots of good quality.