Light-harvesting chlorophyll a/b binding (Lhc) proteins play a key role in the efficiency of the photosynthetic system of plants and participate in the regulation of plant growth, development, and the response to abiotic stress. In this study, 28 PbrLhc genes of the family were identified in the pear Pyrus bretschneideri genome database, which were distributed on 25 of the 27 chromosomes. Phylogenetic relationship analysis demonstrated that PbrLhc proteins could be divided into five subfamilies. Using MEME Suite, PlantRegMap, and Softberry, the conserved motifs, transcription binding sites, and predicated location of all PbrLhc proteins, respectively, were determined. A collinearity relationship using MCScanX software showed that there was a collinearity relationship between different PbrLhc genes. Using the hierarchical clustering method to develop a heat map of gene expression, five genes were found to be down-regulated under irrigation treatment and up-regulated under drought treatment; seven genes were up-regulated under irrigation treatment and down-regulated under drought treatment. Finally, the results of these analyses will provide theoretical basis for future study on the function and differential expression of PbrLhc genes in response to drought stress.

Members of the glycogen synthase kinase 3 (GSK3) family in plants, as a class of serine/threonine protein kinases, have been demonstrated to play crucial roles in a wide range of biological processes and environmental stresses. However, the GSK3 gene family has not been analyzed in pears. In this study, 12 GSK3 gene family members were identified in the Pyrus bretschneideri genome. These genes were located on 10 chromosomes and phylogenetically classified into four subfamilies. All 12 PbGSK3 proteins possessed highly conserved domains. The results demonstrated the structural characteristics of all 12 PbGSK3s and the evolutionary processes of their putative proteins. The presence of several cis-acting elements in the promoter region of the PbGSK3s associated with hormonal and stress responses suggested that the PbGSK3s might be involved in the growth and development of pears and in stress response. The expression profiles of PbGSK3s under drought stress were also analyzed. When the pears were subjected to drought stress for different durations, the expression patterns of 12 PbGSK3s exhibited variations. The findings would provide a scientific foundation for further exploration of the potential functions of the GSK3 genes in pears.