Transcriptome Analysis For Common Walnut Seed During Oil Synthesis Period

Walnut?Juglans regia L.?is an important tree species of woody oil;however,there is little understanding of the metabolism of seed oil at the molecular level.This study based on Illumina HiSeq^TM 4000,the transcriptome sequencing was analyzed and gene functional annotation of J.regia‘Xinxin2'walnut seed lipid conversion during the initial stage?60?70days of post floral referred to as G1?,middle stage?90?100 days of post floral referred to as G2?and end stage?120?130 days of post floral referred to as G3?.And the different genes were did Go function classification and enrichment of KEGG Pathway,discussed the transformation of seed oil and fatty acid biosynthesis,the expression pattern of unsaturated fatty acid biosynthesis and glycerophospholipid metabolism related genes,and their functions are analyzed.The main results were as follows:194 193 unigenes were obtained by RNA-Seq during walnut oil synthesis period,there were 138 862 unigenes homologous in public protein database,accounting for 71.50%of all unigenes.127 127 unigenes were annotated to Nr database;89 211 unigenes were annotated to GO database;52 377 unigenes were commented on classification to KOG database of 25kinds of function;article 53 802 unigenes were annotated to 131 pathways.203503 coding sequences were predicted.9 570 high abundance expression genes at the G1 phase?FPKM>15?,5 425 in G2 phase,6 337 in G3 phase.There were 14 220,6 205 and 14 838 differentially expressed genes respectively in G2 vs G1,G3 vs G2 and G3 vs G1 were up-regulated.The differentially expressed genes of G2 vs G1 significantly enriched in carbohydrate metabolism process,G3vs G2 significantly enriched in metabolic process,G3 vs G1 significantly enriched in metabolic process.Fatty acid biosynthesis and plant hormone signal transduction were significantly enrichment of KEGG Pathway.The oil synthesis of walnut seed in G1 to G3 which associated with biotin carboxylase gene ACAC,carboxyl transferase alpha subunit gene accA,biotin carboxyl carrier protein gene accB and biotin carboxylase subunit gene accC,beta ketone acyl ACP synthase?gene fabF and beta-ketone acyl-ACP reductase gene fabG were continuously up-regulated.There were abundant differentially expressed genes in different stages of walnut lipid conversion period,and the majority of genes were related to metabolism,especially the enrichment genes were higher on the lipid conversion metabolic pathways.This transcriptome analysis provides a theoretical basis and a wealthy data resource for further reserach on the lipid synthesis of walnut.