Analysis of the expression of transcription factors and other genes associated with aleurone layer development in wheat endosperm

Defective kernel1 (dek1), crinkly4 (cr4) and supernumerary aleurone layer 1 (sal1) have been suggested as key genes involved in aleurone differentiation in cereals. Transcription factors (TFs) may play a role in regulation of aleurone development by controlling the expression of genes involved in this process. In this study, expression patterns of TFs in developing aleurone and starchy endosperm tissues of wheat was studied using RNA-Seq. Transcript profiles were obtained for aleurone and starchy endosperm tissues of the cultivar Banks at 6, 9 and 14 days post anthesis (DPA). The M-type, MIKC, MYB, CSD and NF-Y TF families were highly up-regulated, in the aleurone while in the starchy endosperm, PLATZ and Dof families were significantly up-regulated. Cr4 and sal1 homologs were identified on chromosomes 7AL, 7BL and 7DL. Dek1 was identified on chromosomes 6AL, 6BL and 6DL. Expression of dek1, cr4, sal1 and risbz1 was higher at the earlier stages of seed development. Further, we observed, sub-genome level partitioning of dek1 expression, with B and D sub-genome dek1 alleles abundantly expressed at all three stages of aleurone development. Expression of sal1 was significantly higher than that of dek1 and cr4. Aleurone development is probably regulated by several epistatic genes in wheat.