Apomixis and sexual reproduction in Cenchrus ciliare (Paniceae, Poaceae): a molecular approach.

NORES, MARÍA J.; NAGAHAMA, NICOLÁS; PANZETTA-DUTARI, GRACIELA .M Y ANTON, ANA

Rosario, Argentina

Congreso; XLII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2006

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Understanding reproduction in grasses, the most economically important plant family, is relevant from a biological, evolutionary and biotechnological point of view. Apomixis, asexual reproduction through seeds, could be potentially exploited to indefinitely propagate specific genotypes in crops. To study sexual and apomictic reproduction in the aposporic grass Cenchrus ciliare, we performed SDS-PAGE and silver staining of ovary proteins of different developmental stages, verified by cytological investigations. With this approach, differences in protein expression patterns between leaves and ovaries, soluble and membrane ovary proteins and early and late developmental stages were found. We developed polyclonal antibodies that specifically recognize soluble ovary proteins in western blots and constitute useful tools for posterior studies. To look for transcription factors involved in reproduction we performed MADS box genes PCR and RT-PCR studies. We identified two MADS box genes expressed in sexual and apomictic spikelets and ovaries: one similar to class D/C maize ZMM1 and ZmOV23, and the other similar to class E LHS1, which have a demonstrated role in the production of reproductive organs. Cladistic analyses with their grass orthologs contributed to reconstruct gene evolutionary history in the family. These studies will provide new clues regarding reproduction in Cenchrus ciliare