該基因編碼一個成員的鐵氧還蛋白NADP（+）還原酶（FNR）家族的電子轉移酶。該蛋白通過將蛋氨酸合酶再生到功能狀態在蛋氨酸合成中發揮作用。由于蛋氨酸合成需要葉酸供體的甲基轉移，編碼酶的活性對葉酸代謝和細胞甲基化很重要該基因突變可引起同型膀胱尿巨幼細胞性貧血，cbl E型該基因的選擇性剪接導致多個轉錄變體。
This gene encodes a member of the ferredoxin-NADP(+) reductase (FNR) family of electron transferases. This protein functions in the synthesis of methionine by regenerating methionine synthase to a functional state. Because methionine synthesis requires methyl-group transfer by a folate donor, activity of the encoded enzyme is important for folate metabolism and cellular methylation. Mutations in this gene can cause homocystinuria-megaloblastic anemia, cbl E type. Alternative splicing of this gene results in multiple transcript variants.