In order to investigate the role of Cytochrome b5(Cyt b5)and Cytochrome b5 reductase(Cyt b5r)in the electron transport ofcytochrome P450 CYP51 A in Penicillium digitatum,the co-expression mechanism of CYP51 A and Cyt b5-Cyt b5 r in P. digitatum was studied,and its effects on the expression of gene cyp51 A was detected. By analyzing and screening transcriptome as well as PCR cloning,gene cyt b5 andcyt b5 r were acquired and designated as HS-Pdcyt b5 and HS-Pdcyt b5 r. Further,a co-expressed plasmid vector pp...