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Plant invertases comprise a family of enzymes that catalyze the irreversible hydrolysis of sucrose into glucose and fructose, which plays a crucial role in carbohydrate partitioning and regulating plant growth and development. However, currently, there is little information on the roles of invertases in the development of pear trees. In this study, we performed genome-wide identification of a total of 23 invertases from the predicted genome data of the pear plant (Pyrus bretschneideri R.). Based on phylogenetic analysis, the pear invertases could be clustered into 13 acid invertase genes and 10 alkaline/neutral invertase genes. Chromosome location showed that tandem duplication and segmental duplication have played an important role in the expansion of acid and neutral/alkaline invertases in pear plants. Evolutionary analysis of invertases from pear and two model plant species (Arabidopsis thaliana and Oryza sativa) indicated that the evolutionary divergence of invertases occurred before the common ancestor of dicots and monocots. Tissue-specific expression analysis showed that the transcripts of all the identified invertase genes were detectable in various tissues. We hypothesize that the identified invertase genes all participate in regulating pear growth and development.

Background Canopy architecture is critical in determining the light environment and subsequently the photosynthetic productivity of fruit crops. Numerous CCT domain-containing genes are crucial for plant adaptive responses to diverse environmental cues. Two CCT genes, the orthologues of AtPRR5 in pear, have been reported to be strongly correlated with photosynthetic performance under distinct canopy microclimates. However, knowledge concerning the specific expression patterns and roles of pear CCT family genes (PbCCTs) remains very limited. The key roles played by PbCCTs in the light response led us to examine this large gene family in more detail. Results Genome-wide sequence analysis identified 42 putative PbCCTs in the genome of pear (Pyrus bretschneideri Rehd.). Phylogenetic analysis indicated that these genes were divided into five subfamilies, namely, COL (14 members), PRR (8 members), ZIM (6 members), TCR1 (6 members) and ASML2 (8 members). Analysis of exon–intron structures and conserved domains provided support for the classification. Genome duplication analysis indicated that whole-genome duplication/segmental duplication events played a crucial role in the expansion of the CCT family in pear and that the CCT family evolved under the effect of purifying selection. Expression profiles exhibited diverse expression patterns of PbCCTs in various tissues and in response to varying light signals. Additionally, transient overexpression of PbPRR2 in tobacco leaves resulted in inhibition of photosynthetic performance, suggesting its possible involvement in the repression of photosynthesis. Conclusions This study provides a comprehensive analysis of the CCT gene family in pear and will facilitate further functional investigations of PbCCTs to uncover their biological roles in the light response.