Transcriptomic Analysis of Isogenic NUD1 and nud1 Lines

In barley having adherent hulls, an irreversible connection between the pericarp with both palea and lemma is formed during grain maturation. A mutation in the NUDUM 1 (NUD1) gene prevents this connection and leads to the formation of barley with non-adherent hulls. To elucidate the genetic mechanisms of hull adhesion, a genetic model of two isogenic lines was used: a doubled haploid line having adherent hulls and it's derivative with non-adherent hulls obtained by targeted mutagenesis of the NUD1 gene. A comparative transcriptomics analysis of the grain coats was performed at two stages of development: milk stage, when the hulls can still be easily detached from the pericarp, and dough stage, when the hull adhesion process occurs. It was shown that the main differences in the transcriptomes lie in genes related to DNA replication and chromatin assembly, cell wall organization, and cuticle formation. Meanwhile, genes involved in lipid biosynthesis mostly show minor differences in expression between stages and genotypes and represent a limited set of active genes.