Plants that differ in ploidy are reproductively isolated by a hybridization barrier that is established in the endosperm, referred to as triploid block. Our work uncovered a new pathway leading to the formation of small RNAs from transposable elements that establish a hybridization barrier in the endosperm. We currently investigate when during pollen development these siRNA are generated, how are the transported and what is their mode of action in the endosperm.
Wang G, Jiang H, Del Toro de León G, Martinez G, Köhler C (2018) Sequestration of a transposon-derived siRNA by a target mimic imprinted gene induces postzygotic reproductive isolation in Arabidopsis. Developmental Cell 46: 1-10. (PubMed)
Martinez G, Wolff W, Wang Z, Moreno-Romero J, Santos-González J, Liu Conze L, DeFraia C, Slotkin RK, Köhler C (2018) Paternal easiRNAs regulate parental genome dosage in Arabidopsis. Nature Genetics 50:193-198. (PubMed)
Borges F, Parent J-S, van Ex F, Wolff P, Martínez G, Köhler C, Martienssen RA (2018) Transposon-derived small RNAs triggered by miR845 mediate genome dosage response in Arabidopsis. Nature Genetics, 50:186-192. (PubMed)
Martinez G, Köhler, C. (2017) Role of small RNAs in epigenetic reprogramming during plant sexual reproduction. Curr Opin Plant Biol 36: 22–28. (PubMed)