Abstract

Transcription factors (TFs) are essential for the regulation of gene expression and cell fate determination. Characterizing the transcriptional activity of TF genes, in time and in space, is a critical step toward understanding complex biological systems. The vegetative gametophyte of bryophytes resembles some characteristics with the shoot-apical meristem of flowering plants. However, the identity and expression profiles of TFs associated with the organization are largely unknown. With only ~450 TF genes, Marchantia polymorpha is an outstanding model system for systems biology. Here we generated a near-complete collection of promoter elements derived Marchantia TFs. We experimentally tested in planta transcriptional fluorescent reporters for all TFs in the collection and systematically mapped the expression patterns in the Marchantia gemma. This allowed us to delimitate expression domains and identify a unique set of TFs expressed in the stem-cell zone, providing new insight into the dynamic regulation of the gametophytic meristem and its evolution and identify new cell-type specific promoters.