**2.2. cDNA library construction and sequencing by Sanger method**

Total RNA from frozen seed tissue of 4 months of development was extracted using López-Gómez et al.'s protocol with some modifications [20]. The cDNA complementary library was built from 1 μg of total RNA using SMART™ cDNA Library Construction Kit (Clontech). The obtained cDNA sequences were cloned into pTripIEx2 vector. Cleavage experiments were made using *E. coli* BM25.8 cells to obtain the plasmid pTriplEx2. Sequencing reactions were performed using ABI PRISM BigDye Terminators v3.0 kit (Applied Biosystems), by 5′ end of plasmids extracted from random clones. The sequences obtained were filtered by quality using PHRED [21]; vector masked and trimming of poly A/T were performed using LUCY2 software [22] resulting in 5002 high-quality reads.
