[Functional genomics studies of Salvia miltiorrhiza I. Establish cDNA microarray of S. miltiorrhiza].

OBJECTIVE: Establishing cDNA microarray, in order to study functional genomics of Salvia miltiorrhiza. METHOD: Total RNA samples were prepared from S. miltiorrhiza roots using a modified CTAB method. mRNA was isolated by Quichprep Micro mRNA Purification Kit from Pharmacia. Then cDNA was synthesized and cloned into the EcoRI-XhoI sites of the ZAP Express vector using a cDNA synthesis kit, and the ligation mixture was packaged using a ZAP-cDNA Gigapack Gold III cloning kit (Stratagene). The single phage was isolated for PCR amplification, Aliquots of the PCR reactions were analyzed in a 1.5% agarose gel to verify the quality of PCR. The remaining cDNA was purified by Multiscreen filter plates (Millipore) and aliquots were analyzed by agarose gel again to verify the quality of purification. Clones passed verification was resuspended in 15 microL 50% DMSO for arraying. An actin gene from S. miltiorrhiza was used for positive control. PloyA and 50% DMSO was used for negative controls. RESULT: Bacterial colonies containing cNDAs of S. miltiorrhiza were inserted with average insert size of 0. 5 kb to 2. 5 kb. Total 4 354 genes were singled out from the first 8 736 PCR product and used for cDNA microarray manufacture. Single color fluorescence hybridization showed that all positive controls had signals while negative controls had no signals. CONCLUSION: It was the first cDNA microarray about traditional Chinese herbs especially for geoherbs. It could be a powerful tool for studying functional genomics of S. miltiorrhiza.

[Functional genomics studies of Salvia miltiorrhiza II--gene expression profiling of different stage of hairy root].

OBJECTIVE: Studying the gene expression profiling of different stage hairy root of Salvia miltiorrhiza, in order to find functional genes. METHOD: The contents of second metabolites were determined by HPLC and gene expression profiling was detected by cDNA microarray. cDNA labeled with a fluorescent dye (Cy5 and Cy3-dCTP) was produced by Eberwine's linear RNA amplification method and subsequent enzymatic reaction. The microarrays were scanned with a ScanArray Express scanner using ScanArray 2.0 software and quantified by signal intensities of individual spots from the 16-bit TIFF images using GenePix Pro 4.0. The linear normalization method was used for data analyze. Northern blot was used to test the gene expression results obtained by microarray. Different expressed genes were sequenced and analyzed by gap4 software, and then they were analyzed with BLASTX, BLASTN, GO and KEGG. RESULT: Growth rate and second metabolites analysis indicated that the stage from 30 d to 45 d was the growth stage, while the stage from 45 d to 60 d was the second metabolites accumulation stage. Accordingly 30 d hairy root was chosen as a reference, which was hybridized with 45 d and 60 d hairy root separately. Total 203 different expressed genes were obtained. Northern blot showed that the result was identical with the microarray result. After sequenced, there were 172 genes clustered into 114 clusters (Unigenes). Among them, 62 unigenes had known functions, 34 unigenes were hypothetical protein, 9 unigenes were homologues with no similarity and 9 unigenes were unidentified protein with low similarity. Total 67 genes were classified into cellular component ontology, molecular function ontology and biological process ontology based on GO analysis. Total 26 genes, which represented 29 metabolic-related enzymes, were located in metabolic maps based on KEGG pathway classification. CONCLUSION: Several important functional genes related to second metabolite synthesis were cloned such as P450 and copalyl diphosphate synthase genes. cDNA microarray was a useful tool for functional genomics of traditional Chinese medicine.