Cloning, expression, and characterization of miR058 and its target PPO during the development of grapevine berry stone

• The target gene of Vv-miR058 was predicted by bioinformatics.
• The sequence of Vv-PPO was cloned, and its homologous conservation was analyzed.
• The temporal expression profiles of Vv-PPO and Vv-miR058 were investigated.
• The potential target gene Vv-PPO for Vv-miR058 was verified by RLM-RACE.

Polyphenol oxidases catalyzing the oxygen-dependent oxidation of phenols to quinones are ubiquitous among angiosperms. They are key enzymes playing a significant role during the synthesis of lignin. The inhibition of the synthesis of lignin in grapevine can cause seedless grapevine berry development. In this study, grapevine PPO (Vv-PPO) was predicted as the target gene of Vv-miR058 by bioinformatics analysis, and it was further cloned and its homologous conservation in various plants was analyzed. The expression profiles of miR058 and its target Vv-PPO were detected by qRT-PCR in peel, pulp and seeds of three grapevine cultivars and Vv-PPO was expressed in an opposite variation way with Vv-miR058 where both of them could be detected, suggesting that Vv-miR058 can play an important role by regulating the expression of Vv-PPO. In addition, the potential target gene Vv-PPO for Vv-miR058 was verified by RLM-RACE. This result would be helpful in theoretical basis for further research and seedless grapevine berry production.