Relationship between expression of sesquiterpene synthase gene and sesquiterpene content in artificial agarwood induced by Fusarium sp. A2 / 中国药学杂志

OBJECTIVE: To explore the expression of sesquiterpene synthase (gene sesqui-TPS) and dynamic change of sesquiterpene content in the resin-deposited parts of the trunk of Aquilaria sinensis (Lour.) Gilg. induced by Fusarium sp. A2. METHODS: Artificial agarwoods from Aquilaria sinensis were induced by Fusarium sp. A2 using pinhole instillation. The heartwood of Aquilaria sinensis without or with resin were extracted before induction and at 7 time points within one year after induction. The expression of sesqui-TPS was detected by quantitative Real-time PCR. And then the dynamic change of sesquiterpene content in the tissues were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: The relative expression of sesqui-TPS gene in the artificial agarwoods induced by Fusarium sp. A2 from 2 to 12 months were 10.85, 0.793 1, 6.484, 611.4, 5 800, and 4 211 respectively. Sesquiterpene secondary metabolites were not detected in the trunk at 2 months before artificial induction. Fourteen sesquiterpene were detected from 4 to 12 months, with relative percentages of 21.40%, 25.52%, 36.44%, 32.40% and 55.70% at each time point. CONCLUSION: Sesqui-TPS gene is extremely sensitive to Fusarium sp. A2 treatment and responds to late damage. The expression of sesqui-TPS gene lags behind the accumulation of sesquiterpene component, which would provide a foundation for studies on regulation action of function gene for sesquiterpene biosynthase pathway during the formation of agarwood resin in A. sinensis.

Differential Response of Surfactant Protein-A Genetic Variants to Dexamethasone Treatment

PURPOSE: Surfactant protein A(SP-A) is involved in surfactant physiology and structure, and plays a major role in innate host defense and inflammatory processes in the lung. Steroid therapy is widely used for mothers who threaten to deliver prematurely and also used commonly in the management of preterm infants with chronic lung disease. Two SP-A genes(SP-A1, SP-A2) and several alleles have been characterized for each SP-A gene in human. Preliminary evidence indicates that differences may exist among alleles in response to Dexamethasone(Dexa) and that the SP-A 3'UTR plays a role in this process. We studied whether 3'UTR-mediated differences exist among the most frequently found SP-A alleles in response to Dexa. METHODS: Constructs containing the 3'UTR from eight different SP-A alleles were made using luciferase as a the reporter gene. These constructs were driven by the SV40 promotor and were transfected along with a transfection control vector in H441 cells that express SP-A. The activity of the reporter gene in the presence or absence of Dexa(100 nM) treatment was measured. All the experiments for the eight SP-A alleles studied, were performed in triplicate and repeated five times. The results were normalized to the transfection control. RESULTS: Expression of alleles of 6A3, 6A, 1A were significantly decreased in response to Dexa. CONCLUSION: Three UTR mediated differences exist among human SP-A variants both in the basal expression and in response to Dexa. These genotype-dependent differences may point to a need for a careful consideration of individual use of steroid treatment in the prematurely born infant.

Allele Distribution and Frequency of Human Surfactant Protein-A2 in Korean Neonates

PURPOSE: We evaluated allele frequencies and distribution of surfactant protein A2(SP-A2) in Korean neonates in order to estimate the prevalence of RDS, to find out new SP-A alleles, and to establish new steroid therapy. METHODS: Genomic DNA was extracted from 71 neonates and served as a template in PCR for genotype analysis. SP-A gene-specific amplications and gene-specific allele determinations were performed using PCR-cRFLP methods. RESULTS: The distribution for the alleles of the SP-A2 gene in the study population was 1A, 1A0, 1A1, 1A2, 1A3, 1A5, 1A6, 1A7, 1A8, 1A9, 1A11, 1A12. The specific frequencies for the alleles of the SP- A2 gene in the study population were : 1A=11.3%, 1A0=38%, 1A1=12.7%, 1A2=9.2%, 1A5=15.5%, 1A7= 2.9%, 1A8=4.9%, 1A9=2.2%, others=3.3%. CONCLUSION: The frequency of 1A0 was higher than the other SP-A2 alleles in Korean neonates. This finding suggests that the prevalence of RDS in Korea may be low compared with other countries. However, this finding also suggests that Korean neonates have a high risk of infection.