Developmental regulation of oil bodies in Marchantia polymorpha is mediated by MpC1HDZ

ROMANI F; BOWMAN JL; FLORENT SN; FARÍAS S; MORENO JE

Buenos Aires

Congreso; LASDB Meeting 2019; 2019

Latin American Society for Developmental Biology

The Class I Homeodomain Leucine Zipper (C1HDZ) transcription factors (TFs) modulate molecular responses to drought and other molecular functions according to functional studies in angiosperms, but little is known about its role in early diverging land plants. We studied this gene class in the model liverwort Marchantia polymorpha that encodes for a single ortholog of this gene. MpC1HDZ resembles all angiosperm C1HDZ structural features but, in contrast to flowering plants, we did no t detect induction of MpC1HDZ, nor the other gene members of the family, under ABA and osmotic stress treatments. In the same way, loss of function Mpc1hdz plants showed no differential responses under abiotic stress treatments. Interestingly, Mpc1hdz plan ts showed developmental defects in oil body cells idioblastic cells that accumulate secondary metabolites. Consistently, we found that Mpc1hdz is highly expressed during early stages of oil body cell development. Moreover, ectopic overexpression of MpC1H DZ is lethal for Marchantia, while in Arabidopsis induced phenotypes like other C1HDZ gain of function plants, such as leaf serration and drought tolerance. Altogether, this data is consistent with the notion that the role of C1HDZ TFs in the water stress response of seed plants was co opted later in the evolution. C1HDZ TF family provides an example of how TF functionality diversified during land plant evolution.