Gene encoding cytochrome P450 and use thereof

A transformation method comprising the steps of:

• introducing, into a host cell, an expression vector comprising a cytochrome P450 gene encoding a protein comprising the amino acid sequence of SEQ ID NO:2 and an additional gene;
• and selecting, as a transformant, a cell that grows in the presence of at least one inhibitor selected from the group consisting of an acetolactate synthase inhibitor classified as code 2 of Herbicide Resistance Action Committee (HRAC) classifications, a microtubule assembly inhibitor classified as code 3 of HRAC classifications, a photosystem II inhibitor classified as code 6 of HRAC classification, a carotenoid biosynthesis inhibitor in phytoene desaturase (PDS) classified as code 12 of HRAC classifications, a protoporphyrinogen oxidase inhibitor classified as code 14 of HRAC classifications, a dihydropteroate synthase inhibitor classified as code 18 of HRAC classifications, and a 4-hydroxyphenylpyruvate dioxygenase inhibitor classified as code 27 of HRAC classifications.