Cloning And Its Response To Pseudomonas Syringae Pv.actinidiae Of PR2 Protein Gene In Actinidia Eriantha Benth

Kiwifruit bacterial canker is a devastating disease caused by Pseudomonas syringae pv.actinidiae(PSA).It had seriously affected the quality and yield of kiwifruit and brought severe economic losses to the kiwifruit industry worldwide.At present,the prevention and treatment of kiwifruit canker disease is mainly chemical control.However,the use of a large number of chemical pesticides will affect the quality and safety of kiwifruit products.Therefore,the cultivation of resistant cultivars is an important means to effectively deal with the harm of kiwifruit canker disease.Nevertheless,compared with traditional breeding,transgenic resistance breeding can transfer specific disease-resistant genes into kiwifruit,which is the genetic improvement of kiwifruit.And this breeding method can greatly shorten the breeding period and accelerate the process of disease resistance breeding.In this study,the leafs of Actinidia eriantha Benth were used as the test material.Starting from the cloning of PR2 protein gene which may have disease resistance function according to the preliminary study.Then,subcellular localization and resistance identification of PR2 protein gene were made which aimed to provide genetic resources and molecular basis for the transgenic resistance breeding of kiwifruit.The results are as follows:(1)The PR2 protein gene which has a total length of 732 bp and a complete open reading frame of 732 bp,encoding 243 amino acids was cloned successfully.(2)Fusion protein expression vector 35S:PR2-GFP was constructed,and was successfully transformed into agrobacterium tumefacien competent cells GV3101 by freeze-thaw method.(3)The empty carrier 35S:GFP and fusion protein expression vector 35S:PR2-GFP were instantaneously transformed into Nicotiana Benthamiana successfully.And then,the analysis of subcellular localization and resistance identification were carried out.Subcellular localization results showed that the PR2 protein gene was located in the nucleus and cytoplasm.And the results of resistance identification showed that the N.Benthamiana leafs with the empty carrier 35S:GFP appeared hypersensitive response(HR)after the inoculation of PSA.However,the N.Benthamiana leafs with the fusion protein expression vector 35S:PR2-GFP had no symptoms or mild symptoms.This confirmed that the PR2 protein gene has certain canker resistance function.