Omics-based Study On Genes Related To Volatile Terpenoids From Matricaria Chamomilla .L

German chamomile(Matricaria chamomilla.L),an annual herb from Asteraceae family,is one of the most world-wide used medicinal plants,which were proved has anti-inflammatory,antibacterial,anti-oxidative,antihypertensive,lipid-lowering and anti-tumor effects.German chamomile is rich in volatile terpenoids.We compared the transcriptome data with the results of HS-SPEM-GC-MS detection of volatile constituents in German chamomile,and constructed the co-expression network between terpenoids-related genes.Moreover,we identified and cloned one of key genes involved in terpenoids biosynthesis pathway,Farnesyl pyrophosphate synthase(FPS).The main results are as follows:1.Ten samples of German chamomile were sequenced by BGISEQ-500 platform,including different organs and flowers in different developmental stages,and the average output of 23.99 M data was obtained.An average of 81.61% data were aligned to reference,and a total of 110,463 Unigenes were detected.2.The volatile components of different organs and flowers in different developmental stages from German chamomile were detected by HS-SPEM-GC-MS.118 kinds of volatile compounds were identified,including 51 sesquiterpenes,18 monoterpenes,21 esters and 28 other components.3.By combining with the transcriptome data and the components contents detected by HS-SPEM-GC-MS from German chamomile,a co-expression network of was constructed,a total of 152 unigenes related to 34 terpenoids synthesis were identified,which 91 unigenes of those showed correlation with volatile terpenoids.4.FPS gene,a key gene for the synthesis of terpenoids,was cloned from German chamomile.The open reading frame(ORF)was 1,032 bp,encoding 343 amino acids;the deduced amino acid molecular weight was 39.5k Da.The prokaryotic expression vector of p ET-32a-FPS was constructed,and it was expressed in Escherichia coli BL21(DE3),then the recombinant protein was purified.The purified protein was used to detect the bioactivity of enzyme reaction in vitro.The result showed that FPS proteins have biological activity.5.The expression levels of FPS gene in different organs were detected by qPCR.The results showed that FPS gene had the highest expression level in flowering tubular flowers.6.The pK7GWF2.0-FPS vector was constructed using Gateway technology,and transformed into Agrobacterium tumefaciens,then transiently expressed by injecting into tobacco leaves,and photographed under laser confocal microscope.The results showed that the recombinant protein was located on the chloroplast.