Genome-Wide Identification and Expression Analysis of the fw2.2-like Gene Family in Pear

Fruit size is a major factor determining yield, quality, and consumer acceptability. fw2.2 (fruit weight-2.2) primary quantitative trait locus that was the first to be cloned, accounting for 30% of variation in tomato fruit size. The various homologs (fw2.2-like) have been identified many plants belong large family. To date, there has no report carried out comprehensive identification fw2.2-like members pear. In this study, total 14 genes were pear (Pyrus bretschneideri Rehd) genome designated as PbFWL1-14. All PbFWL unevenly distributed on nine chromosomes, each chromosome contained between one four genes. proteins more than two conserved motifs, intron, same subfamily seemed similar intron gene structure. According neighbor-joining phylogenetic tree, 78 fw2.2/CNR (cell number regulator) from five plant species, including pear, maize, tomato, peach, rice, physalis, could divided into seven subgroups, mainly subgroups 1, 3, 4, 5, 6. Ka/Ks analysis also revealed family may subjected strong purifying selection pressure during its evolution. A cis-element found cis-elements responsive hormones stress discovered promotion regions all PbFWLs. When combining real-time PCR detection results, PbFWL1/2/5 most likely candidate regulating