Genome-wide identification and expression analysis of protein arginine methyltransferase and JmjC domain-containing family in apple.

Histone methylation is an important type of histone modification that regulates gene expression in plants. In this study, we identified 14 arginine methylation-related genes (, ) and 32 demethylation-related genes (, ) in apple. Furthermore, we investigated the phylogenetic relationship, chromosome distribution, gene structure, motif analysis, promoter sequence analysis, and expression patterns of and genes. Homology analysis showed a high degree of conservation and homology between and genes in and apple. We identified the types of duplicated genes in the and gene families, found a large number of whole-genome duplicates (WGD) gene pairs and a small number of tandem duplicates (TD) pairs, transposed duplication (TRD) gene pairs as well as proximal duplicates (PD) pairs, and discussed the possible evolutionary pathways of the gene families from the perspective of duplicated genes. Homology analysis showed a high degree of conservation and homology between and genes in and apple. In addition, the promoter regions of and contain numerous -acting elements involved in plant growth and development, hormone response, and stress responses. Based on the transcriptional profiles of and in different tissues and developmental stages, it was found that and may play multiple roles in apple growth and development, for example, may be involved in the regulation of apple endosperm formation. and exhibit different expression patterns in response to hormone signaling in apple, , , , , , and may play roles in apple response to drought stress, while the expression of , , , and is affected by cold stress. Our study provides a foundation for determining the functional roles of and genes in apple.