Fig. 7
Characterization of complex transporter-mediated model of carbon allocation and energy supply for oil synthesis in developing P. sibirica seeds. The identified intracellular metabolite transport routes of carbon allocation and energy supply for oil synthesis are mainly based on a combination of our previous 454 sequencing data analysis and qRT-PCR detection. The background color distinguishes different subcellular locations and/or pathways as follows: Light green signifies a direct involvement in glyoxysomal glyoxylate cycle and β-oxidation; light blue signifies a cytosolic location; yellow signifies mitochondrial TCA cycle; orange signifies plastidial glycolysis and OPPP; light purple signifies the vacuole; pink signifies the ER membrane. Dark purple arrows represent the transports of metabolite and energy across intracellular membrane by specific transporters. All transporters involved in carbon flux allocation and energy provision for oil synthesis and TAG mobilization are shown in yellow. Abbreviations for the transporters, enzymes and metabolites are as follows: AAC ATP/ADP carrier, ACBP acyl-CoA-binding protein, ACO aconitase, ACX acyl-CoA oxidase, ADNT adenine nucleotide carrier, AtUTr nucleotide sugar transporter, BASS pyruvate (PYR) carrier (bile acid: sodium symporter family protein), BOU acetyl-carnitine/carnitine carrier, BT1L adenine nucleotide uniporter, CN cetane number, CFPP cold filter plugging point, CP cloud point, CTS COMATOSE, CYS citrate synthase, D density, DIC dicarboxylate carrier, DTC dicarboxylate/tricarboxylate carrier, ER endoplasmic reticulum, ER-ANT1 ER membrane ATP transporter, F6P fructose-6-phosphate, FAMEs FA methyl esters, FAX FA exporter, GAP glyceraldehyde 3-phosphate, GLT glycolipid transporter, GPT glucose-6-phosphate (G6P) transporter, ICL isocitrate lyase, IV iodine value, KAT 3-ketoacyl-CoA thiolase, KV kinematic viscosity, LACS long-chain acyl-CoA synthase, LTPs lipid transfer proteins, MLS malate (Mal) synthase, gMDH glyoxysomal NAD-Mal dehydrogenase, MPC1 PYR carrier, NTT nucleoside triphosphate (NTP) transporter, OPPP oxidative pentose phosphate pathway, OS oxidation stability, PC phosphatidylcholine, PEPCK phosphoenolpyruvate (PEP) carboxykinase, PHT phosphate (Pi) transporter, PIC Pi carriers, PNC peroxisomal adenine nucleotide carrier, PPT PEP transporter, PRK phosphoribulokinase, RBCS ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) small subunit, RPE ribulose-5-phosphate (Ru5P) epimerase, RPI ribose 5-phosphate isomerase, SBP sedoheptulose-bisphosphatase, SDP1 sugar dependent 1, SFC succinate (SUC)/fumarate carrier, SUT sucrose transporter, TA transaldolase, TAG triacylglycerol, TAGL TAG lipase, TCA tricarboxylic acid, TK transketolase, TMT tonoplast monosaccharide transporter, TPT triose phosphate (TP) transporter, VGT vacuolar glucose transporter, XPT xylulose 5-phosphate (X5P)/phosphate transporter