Transcriptome Analysis Of A Cotton Virescent Mutant By Space Mutation

CCRI58vsp is a cotton virescent mutant come from CCRI58induced by space. The phenotype ofthe mutant is yellow from the first true leaf until the end of full-bloom stage, every new leaf showsyellow and this phenotype can last for10days. Take the day true leaf flattening as leaf age0day, theyellow phenotype is the most obvious at the leaf age3days, after that, the leaf begins to turn greenfrom leaf margin, and10days later, the leaf color restores normally as green leaf. This mutant isaffected easily by light intensity, the yellow phenotype is more obvious in sunny days than that incloudy days, even turns to green in continuous overcast days. In this research, according to thedifferent performance in sunny days and in cloudy days, we set two light conditions: high lightintensity and low light intensity. CCRI58and CCRI58vsp were planted in low light conditions andhigh light conditions respectively, RNA of the first true leave was extracted for transcriptomesequencing, through comparison and bioinformatics analysis of three materials, we got someimportant genes that may be virescent gene or related genes and virescent properties related pathways,aiming to explore the mechanism of virescent mutant. The main results are as follows:1.We got87,407、88,664、92,665unigenes according to the first true leave transcriptomesequencing of CCRI58and CCRI58vsp under low light、CCRI58vsp under high light condition, afterhomologous transcripts clusting, we obtained89,020All-unigenes. Compared with NR、NT、Swiss-Prot、KEGG、COG and GO six databases by Blastn and Blastx,63,350、58,617、37,406、33,348、20,961、30,226respectively were annotated. Then we did NR、COG、GO classification.2.Compared with the KEGG database,33,348unigenes received comments, involving126metabolic pathways. Set FDR≤0.001and took the expression difference more than two times asdifferentially expressed genes, comparing mutant CCRI58vsp and wild type CCRI58under low light,we got1457differentially expressed genes, containing1075up-regulated genes and382down-regulated genes in CCRI58vsp; comparing mutant CCRI58vsp under high light and CCRI58under low light, we got13,317differentially expressed genes, containing9306up-regulated genesand3957down-regulated genes in CCRI58vsp.3.Comparing the transcriptome of CCRI58vsp and CCRI58under low light, and comparing thetranscriptome of high light CCRI58vsp and low light CCRI58, then taking two sets ofdown-regulated genes overlap in CCRI58vsp, we could get the mutant gene or pathways related tovirescent phenotype. In the overlap of down-regulated genes, we found5genes down-regulated ratiovery large which may be the mutant gene and two important metabolic pathways related to virescentphenotype, they are1-deoxy-D xyulose-5-phosphate synthetase gene,2-oxoglutarate-dependentdioxygenase gene， ACC synthase gene,1-aminocyclopropane-1-carboxylate oxidase gene，glutathione transferase gene, and diterpenoids synthesis pathway and phenylpropanoid biosynthesispathway.