Abstract
Distantly related maize (Zea mays L.) inbred lines exhibit an exceptional degree of structural genomic diversity, which is probably unique among plants. This study systematically investigates the developmental and genotype-dependent regulation of the primary root transcriptomes of a genetically diverse panel of maize F1-hybrids and their parental inbred lines. While we observed substantial transcriptomic changes during primary root development, we demonstrated that hybrid-associated gene expression patterns including differential, non-additive and allele-specific transcriptome profiles are particularly robust against these developmental fluctuations. For instance, differentially expressed genes with preferential expression in hybrids are highly conserved during development in comparison to their parental counterparts. Similarly, in hybrids a major proportion of non-additively expressed genes with expression levels between the parental values were particularly conserved during development. Importantly, in these expression patterns non-syntenic genes that evolved after the separation of the maize and sorghum lineages are systemically enriched. Furthermore, non-syntenic genes are substantially linked to the conservation of all surveyed gene expression patterns along primary root development. Among all F1-hybrids, between ~40% of the non-syntenic genes with unexpected allelic expression ratios and ~60% of the non-syntenic differentially and non-additively expressed genes are conserved and thus robust against developmental changes. Hence, the enrichment of non-syntenic genes along primary root development might be involved in the developmental adaptation of maize roots and thus the superior performance of hybrids.
You can find more here: https://academic.oup.com/jxb/advance-article/doi/10.1093/jxb/erz452/5602573?guestAccessKey=08f14709-be4e-41b1-95aa-5badd9187b2c