RT Journal Article SR Electronic T1 Transcriptional and morpho-physiological responses of Marchantia polymorpha upon phosphate starvation JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.09.16.300814 DO 10.1101/2020.09.16.300814 A1 Felix Rico-Reséndiz A1 Sergio Alan Cervantes-Pérez A1 Annie Espinal-Centeno A1 Melissa Dipp-Álvarez A1 Araceli Oropeza-Aburto A1 Enrique Hurtado-Bautista A1 Andres Cruz-Hernández A1 John L. Bowman A1 Kimitsune Ishizaki A1 Mario A. Arteaga-Vázquez A1 Luis Herrera-Estrella A1 Alfredo Cruz-Ramírez YR 2020 UL http://biorxiv.org/content/early/2020/09/18/2020.09.16.300814.abstract AB Phosphate (Pi) is a pivotal nutrient that constraints plant development and productivity in natural ecosystems. Land colonization by plants, more than 470 million years ago, evolved adaptive mechanisms to conquer Pi-scarce environments. However, little is known about the molecular basis underlying such adaptations at early branches of plant phylogeny. To shed light on how early divergent plants respond to Pi limitation, we analyzed the morpho-physiological and transcriptional dynamics of Marchantia polymorpha upon Pi starvation. Our phylogenomic analysis highlights some gene networks present since the Chlorophytes and others established in the Streptophytes (eg. PHR1-SPX1 and STOP1-ALMT1, respectively). At the morpho-physiological level, the response is characterized by the induction of phosphatase activity, media acidification, accumulation of auronidins, reduction of internal Pi concentration and developmental modifications of rhizoids. The transcriptional response involves the induction of MpPHR1, Pi transporters, lipid turnover enzymes and MpMYB14, an essential transcription factor for auronidins biosynthesis. MpSTOP2 up-regulation correlates with expression changes in genes related to organic acid biosynthesis and transport, suggesting preference for citrate exudation. Analysis of MpPHR1 binding sequences (P1BS) shows enrichment of this cis regulatory element in differentially expressed genes. Our study unravels the strategies, at diverse levels of organization, exerted by M. polymorpha to cope with low Pi availability.Significance Statement This study unravels the transcriptional and morphophysiological mechanisms executed by the non-vascular, and rootless, plant Marchantia polymorpha upon phosphate starvation conditions. The findings in this study shed light on the mechanisms that early land plants may have developed for the conquest of substrates poor in available phosphate, some of which are still conserved by current-day plants. Moreover, our results open several working hypotheses and novel perspectives for the study of Pi-starvation responses along plant evolution.Competing Interest StatementThe authors have declared no competing interest.