Bacterial-type PEPC genes identification and expression in developing seeds from four oil crops

Bacterial-type PEPC genes were cloned from four oil crops(rape,soybean,peanut and sesame).Their sequences of conserved domains(BOX I to BOX IV) and PEPC activity sites were characterized.The genes included Bna10093361,Bna1009749 and Bna10093360 from Brassica napus,Glyma10g34970.1,Glyma01g22840.1 and Glyma02g14500.1 from Glycine max,SIN1018296 from Sesamum indicum,AhPPC5 from Arachis hypogaea.The 8 genes were commonly composed of 19 to 21 introns,and contained one unique and highly divergent insertion of about 356 to 600bp.PEPC sequences had R/KNTG in C-terminal tetrapeptide,but lacked the phosphorylation motif at N terminus.Results from RT-qPCR showed that Bna10093360 expressed with less than 0.1% of rapeseed BnaActin,Glyma10g34970.1 and Glyma02g14500.1 expressed with less than 2% of soybean GlymaActin.AhPPC5 expressed 32% to 175% of peanut AhActin,and SIN1018296 expressed 3% to 18% of sesame SINActin.The expression trends of AhPPC5 and SIN1018296 were higher at early seed developing stage and then decreased.Results indicated that the bacterial-type PEPC gene functions were widely differentiated.