Cloning and dynamic expression analysis of EC genes in Pyrus pyrifolia induced by thermotherapy

• 1、College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
• 2、 The Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China
• 3、The Key Laboratory of Plant Pathology of Hubei Province, Huazhong Agricultural University, Wuhan 430070, China

Abstract：Thermotherapy is used widely to eliminate viruses from fruit trees. Previous studies mainly focused on the efficiency of elimination viruses from hosts. However it is rarely understood to the interactions between hosts and virus during thermotherapy. In this study, the relationship of ASGV titers and the dynamic expression of chitinase (EC) screened from the reverse library in in vitro Pyrus pyrifolia "huanghua" plants during thermotherapy were further analyzed by RT-PCR and Real-time RT-PCR. The results indicated the expression quantity of EC gene were obviously decreased from 1d to 35d during thermotherapy and reached the lowest point at 35d, while the titers of ASGV in Pyrus pyrifolia decreased significantly from 1d to 10d, and no ASGV signal was detected from 10d to 35d. which will be helpful to know the relationship of EC dynamic expression titers and virus titers during the periods of heat treatment, and provide some information for further study the molecular mechanism of thermotherapy elimination viruses from pear plants. Full-length cDNA sequences of EC genes were cloned and analyzed. The results showed that the full-length cDNA sequence of 1053 bp from EC were obtained, which encoded 334 aa. The Blast search results showed the highest sequence identity of 86.9% at aa level of EC gene with that of Pyrus pyrifolia "huangguan" (GenBank accession No. FJ589784). The results provide materials for further study of EC gene protein function.

Keywords： Thermotherapy sand pear chitinase gene Real-time polymerase chain reaction