Comparative analysis of the Accelerated Aged seed transcriptome profiles of maize CSSLs (I178 and X178)

Seed longevity is one of the most essential characters of seed quality. Two Chromosome segment substitution lines (CSSL) I178 and X178 with significant difference on seed longevity were subjected to transcriptome sequencing before (0d-AA) and after five days of accelerated ageing (5d-AA) treatments. Compared to the non-accelerated ageing treatment (0d-AA), 286 and 220 differential expressed genes (DEGs) were identified in I178 and X178, respectively Among those, 98 DEGs were detected in both I178 and X178 after 5d-AA, Enriched GO terms included cellular components of cell part, intracellular part, organelle and membrane etc., including carbohydrate derivative catabolic process, carbohydrate synthesis, sugar isomerase (SIS) family protein etc. Transcriptome analysis of I178 and X178 showed that Alternative splicing (AS) occurs in 63.6% of the expressed genes in all samples. Only 381 genes specifically occurred AS in I178 and X178 after 5d-AA, mostly enriched in nucleotide and nucleoside binding. Combined with the reported QTL mapping result, the DEG and the AS information, 13 DEGs in the mapping intervals and 7 AS-DEGs were potential candidates may directly or indirectly associated to seed ageing.