SSR markers in transcripts of genes linked to post-transcriptional and transcriptional regulatory functions during vegetative and reproductive development of Elaeis guineensis

In the current study, 6,103 non-redundant ESTs derived from cDNA libraries of developing vegetative and reproductive tissues were annotated and searched for simple sequence repeats (SSRs). Primer pairs from sequences flanking 289 EST-SSRs were tested to detect polymorphisms in elite breeding parents and their crosses. 230 of these amplified PCR products, 88 of which were polymorphic within the breeding material tested. A detailed analysis and annotation of the EST-SSRs revealed the locations of the polymorphisms within the transcripts, and that the main functional category was related to transcription and post-transcriptional regulation. Indeed, SSR polymorphisms were found in sequences encoding AP2-like, bZIP, zinc finger, MADS-box, and NAC-like transcription factors in addition to other transcriptional regulatory proteins and several RNA interacting proteins.The identification of new EST-SSRs that detect polymorphisms in elite breeding material provides tools for molecular breeding strategies. The identification of SSRs within transcripts, in particular those that encode proteins involved in transcriptional and post-transcriptional regulation, will allow insight into the functional roles of these proteins by studying the phenotypic traits that cosegregate with these markers. Finally, the oil palm EST-SSRs derived from vegetative and reproductive development will be useful for studies on the evolution of the functional diversity within the palm family.Oil palm (Elaeis guineensis Jacq.), a perennial monocotyledonous tropical crop species that belongs to the family Arecaceae, is now the world's number one source of edible vegetable oil, and also the richest dietary source of provitamin A. While the worldwide demand for palm oil increases each year, new elite genotypes from traditional breeding programs provide a yield increase of only 1% per year and the long selection cycle (10-12 years) makes genetic improvement slow [1]. Furthermore, to increase overall oil produc