Molecular characterization of PSEUDO RESPONSE REGULATOR family in Rosaceae and function of PbPRR59a and PbPRR59b in flowering regulation
Zhe Liu,
Weijuan Liu,
Zhangqing Wang,
Zhihua Xie,
Kaijie Qi,
Dong Yue,
Yu Li,
Shaoling Zhang,
Juyou Wu,
Peng Wang
Affiliations
Zhe Liu
School of Pharmacy, Changzhi Medical College
Weijuan Liu
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Zhangqing Wang
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Zhihua Xie
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Kaijie Qi
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Dong Yue
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Yu Li
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Shaoling Zhang
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Juyou Wu
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Peng Wang
Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University
Abstract Background PSEUDO RESPONSE REGULATOR (PRR) genes are essential components of circadian clock, playing vital roles in multiple processes including plant growth, flowering and stress response. Nonetheless, little is known about the evolution and function of PRR family in Rosaceae species. Results In this study, a total of 43 PRR genes in seven Rosaceae species were identified through comprehensive analysis. The evolutionary relationships were analyzed with phylogenetic tree, duplication events and synteny. PRR genes were classified into three groups (PRR1, PRR5/9, PRR3/7). The expansion of PRR family was mainly derived from dispersed and whole-genome duplication events. Purifying selection was the major force for PRR family evolution. Synteny analysis indicated the existence of multiple orthologous PRR gene pairs between pear and other Rosaceae species. Moreover, the conserved motifs of eight PbPRR proteins supported the phylogenetic relationship. PRR genes showed diverse expression pattern in various tissues of pear (Pyrus bretschneideri). Transcript analysis under 12-h light/ dark cycle and constant light conditions revealed that PRR genes exhibited distinct rhythmic oscillations in pear. PbPRR59a and PbPRR59b highly homologous to AtPRR5 and AtPRR9 were cloned for further functional verification. PbPRR59a and PbPRR59b proteins were localized in the nucleus. The ectopic overexpression of PbPRR59a and PbPRR59b significantly delayed flowering in Arabidopsis transgenic plants by repress the expression of AtGI, AtCO and AtFT under long-day conditions. Conclusions These results provide information for exploring the evolution of PRR genes in plants, and contribute to the subsequent functional studies of PRR genes in pear and other Rosaceae species.
