Live and let die: a REM complex promotes fertilization through synergid cell death inArabidopsis

Marta Adelina Mendes, Rosalinda Fiorella Guerra, Beatrice Castelnovo, Yuriria Silva-Velazquez, Piero Morandini, Silvia Manrique, Nadine Baumann, Rita Groß-Hardt, Hugh Dickinson, Lucia Colombo
2016 Development  
Fertilization in flowering plants requires a complex series of coordinated events involving interaction between the male and female gametophyte. We report here molecular data on one of the key events underpinning this process -the death of the receptive synergid cell and the coincident bursting of the pollen tube inside the ovule to release the sperms. We show that two REM transcription factors, VALKYRIE (VAL) and VERDANDI (VDD), both targets of the ovule identity MADS-box complex
more » ... mplex SEEDSTICK-SEPALLATA3, interact to control the death of the receptive synergid cell. In vdd_1/+ mutants and VAL_RNAi lines we find that GAMETOPHYTIC FACTOR 2 (GFA2), required for synergid degeneration, is down regulated, while FERONIA (FER) and MYB98 expression, necessary for pollen tube attraction and perception remain unaffected. We also demonstrate that the vdd_1/+ phenotype can be rescued by expressing VDD or GFA2 in the synergid cells. Taken together, our findings reveal that the death of the receptive synergid cell is essential for the maintenance of the following generations, and that a complex formed of VDD and VAL regulate this event.
doi:10.1242/dev.134916 pmid:27338615 fatcat:rq3i5nbfqbcopgj6u3t2lfvvrm