Abstract
MADS-box genes encode transcription factors and are involved in development of flowers in flowering plants. It has been reported that MADS-box genes are expressed in gymnosperms, a fern, a moss and green algae. It is important to clear the role of MADS-box genes in non-flowering plants for understanding the evolution of MADS-box genes and the evolution of flower. However, there is no report of the functional analyses of MADS-box genes of non-flowering plants. In this study, we analyzed six MIKCc-type MADS-box genes (PPM1, PPM2, PpMADS1, PpMADS5, PpMADS6, and PpMADS-S) of a moss, Physcomitrella patens. Expression analysis of knock-in GUS-fusion proteins revealed that they were expressed in protonema, gametophore, rhizoid, gametangia and sporophyte. There is no notable morphological difference in each knock-out line. However, we found that the number of gametophores which produced sporophyte in ppm1ppm2ppmads1 triple knoce-out line was decreased. Phenotypic analyses of multiple knock-out mutants will be presented.
