Marchantia polymorpha linkage map

Marchantia polymorpha has recently become a prime model for cellular, evo-devo, synthetic biological, and evolutionary investigations.We present a chromosomal-scale assembly of the M. polymorpha genome making comparative genome structure analysis and classical genetic mapping approaches feasible.We anchored 88% of the M. polymorpha draft genome to a high-density linkage map resulting in eight pseudomolecules. We found that the overall genome structure of M. polymorpha is in some respects different from that of the model moss Physcomitrella patens. Specifically, recombination rates are greatest in the middle of the chromosome arms like in most vascular plant genomes, which is in contrast to P. patens where recombination rates are evenly distributed along the chromosomes. Nevertheless, some other properties of the genome are shared with P. patens. As in P. patens, DNA methylation in M. polymorpha is spread evenly along the chromosomes, which is in stark contrast to Arabidopsis thaliana, where DNA methylation is strongly enriched at the centromeres. Nevertheless, DNA methylation and recombination rate are anticorrelated in all three species.Taken together, the chromosomal-scale genome assembly we present opens new avenues for M. polymorpha research by linking the physical and genetic maps, making novel genomic and genetic analyses, including map-based cloning, feasible.