With cDNA from Phellodendron amurense seedlings treated with drought stress as tester and cDNA from this plant in normal growth as driver, we construct cDNA subtracted library using suppression subtractive hybridization (SSH). In the library, the rate of recombination was 95%, the size of inserts was 300-800 bp. Two hundred and sixty-five new genes were obtained by DNA sequencing 816 positive clones picked randomly, and partitioned to 16 classes after nucleotide Blast and BlastX homological analysis against NT, NR, SWISSPROT, KEGG database. Forty-four drought stress associated genes, such as heat shock protein cognate 70, dehydration responsive protein 22, universal stress protein, metallothionein II, late embryogenesis abundant protein, were obtained, which made 16.6% of the overall genes. These genes included osmotic regulator, signal component regulatory protein and antioxidant enzyme. The research had established a basis for cloning stress resistance genes and further studying genes expression in P. amurense seedlings under drought stress.
Adaptation, Physiological ; genetics ; Cloning, Molecular ; Droughts ; Gene Expression ; Gene Expression Profiling ; Gene Library ; Nucleic Acid Hybridization ; methods ; Phellodendron ; genetics ; growth & development ; physiology ; Seedlings ; genetics ; physiology

Objective:To describe the current status of registration and design characteristics of clinical trials of new drugs for curing hepatitis B through domestic and foreign websites, so as to provide references for the follow-up clinical trials of new hepatitis B drugs.Methods:A search was conducted on the US Clinical Trials Database and the Chinese Clinical Trial Registry Center. The search date was from the establishment of the database to May 26, 2020, and the registration trials of new drugs for curing hepatitis B at home and abroad were included. Two researchers independently searched and screened the literature and extracted the data.Results:A total of 106 registered clinical trials of new drugs for curing hepatitis B were included (94 English registration websites and 12 Chinese registration websites), and the number of registrations had increased year by year. Among them, the proportion of therapeutic vaccines and core protein inhibitors were the highest, accounting for 27.4% ( n = 29) and 22.6% ( n = 24), respectively. The vast majority of clinical trials ( n = 96, 90.6%) were in the early stages (Phase I and II). The subjects in phase I clinical trial were mainly healthy people and treated CHB patients, while the subjects in phase II clinical trial were mainly CHB patients who had achieved viral suppression after initial or post-treatment. The main evaluation indicators of Phase I clinical trials were the safety and tolerability of new drugs. The main evaluation indicators in about half of Phase II clinical trials were HBsAg negative conversion/quantitative decline. Overall, the number of clinical trials with the new design was small, accounting for 3.8% (4 / 106). There were relatively few trials of new drugs for curing hepatitis B on domestic registration websites, and the information provided was incomplete. Conclusion:The number of clinical trials of new hepatitis B drugs at home and abroad is increasing year by year, but most of them are in phase I and II, with few adopting new designs. In addition, the information integrity of the domestic website registration center needs to be improved.