Fig. 2

Gene expression pattern for Suc metabolism. a Schematic Suc metabolic pathways in oil-rich tubers of Cyperus esculentus. Enzyme or protein names are indicated in blue. For each enzyme or protein, the width of the arrow indicates the gene expression level (FPKM, average fragments per kilobase of exon model per million mapped reads). Black and purple arrows indicate respectively the common and different gene expression patterns in Cyperus esculentus tuber from those in other plant examined in this study. Transporter was marked by the black arrow across red oval. FPKM values of the different isoforms and/or subunits are average transcript levels. Red numbers in black bracket show the numbers of unigenes with more than 1 of FPKM for each enzyme or protein. Abbreviation: CIN, cytoplasmic invertase; CWIN, cell wall invertase; F6P, fructose-6-phosphate; FK, fructokinase; Fru, fructose; G1P, glucose-1-phosphate; G6P, glucose-6-phosphate; Glc, glucose; Hexose-P, hexose-phosphate; HT, hexose transporter; HXK, hexokinase; PD, plasmodesmata; PGI, phosphoglucoisomerase; PGM, phosphoglucomutase; S6P, succose-6-phosphate; SPP, sucrose-phosphatase.; SPS, sucrose-phosphate synthase; Suc, sucrose; SUS, sucrose synthase; SUT, sucrose transporter; T6P, trehalose-6-phosphate; TPS, trehalose-6-phosphate synthase; TST, tonoplast sucrose transporter; SWEET, Sugars Will Eventually be Exported Transporter (hexose and sucrose transporter); UDP-Glc, uridine diphosphate glucose; UGP, UDP-Glc pyrophosphorylase; VIN, vacuolar invertase. b Expression levels for Suc metabolism genes. Left, The distribution of transcript contents among the three pathways. Right, FPKM per protein in each pathway. Without regard to separation of close paralogs or allelic transcripts, multiple protein isoforms or subunits of a multi-protein complex were considered as a single protein and their transcripts were summed (Additional file 1: Table S3)