To our knowledge, this is the first characterisation of a single gene which regulates the initiation of both of these organs! Future work will have to find what SCLA regulators are doing in other land plant lineages.

MpGRAS7 responsiveness to environmental cues therefore allows the liverworts to make strategic decisions about the timing of each reproductive strategy depending on a conducive environment.

Conversely, the sexual gametangiophores have a delayed emergence - meaning that gras7 mutants are shifted towards asexual propagation. From our data, we concluded that MpGRAS7 is a negative regulator of asexual initiation, and a positive regulator of sexual initiation.

We generated gras7 mutants, and when investigating the asexual gemma cups, we found that gras7 mutants produced them more frequently. We also found that the dormancy of these cups was broken when compared to wild-type

Furthermore, we found the gene to be responsive to several abiotic cues, including extended Far-Red light irradiation, as well as humidity stress, and abscisic acid application

We first started work on this gene because we found it responsive to Phytophthora infection in Marchantia, but early on we found its expression in reproductive organs intriguing… MpGRAS7 is expressed in asexual gemma cups, as well as sexual reproductive organs (gametangiophores)

MpGRAS7 is a GRAS-domain transcriptional regulator, from a sub-family which had no characterised function despite being conserved across land plants - possibly because of the loss of this gene in the model plant Arabidopsis thaliana

I am very excited to be sharing our new @dromius lab pre-print on a Marchantia gene MpGRAS7, with contributions from @Phil_Carella and @YangWeibing biorxiv.org/content/10.1101/…