AUTHOR=Li Guangli , An Tianyue , Li Yu , Yue Jinyang , Huang Ruoshi , Huang Jia , Liang Jincai , Yao Wei , Huang Liufang , Chen Yidu , Zhang Rongrong , Ji Aijia , Duan Lixin 

TITLE=Transcriptome Analysis and Identification of the Cholesterol Side Chain Cleavage Enzyme BbgCYP11A1 From Bufo bufo gargarizans

JOURNAL=Frontiers in Genetics

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/genetics/articles/10.3389/fgene.2022.828877

DOI=10.3389/fgene.2022.828877

ISSN=1664-8021

ABSTRACT=<p><italic>Bufo bufo gargarizans</italic> Cantor are precious medicinal animals in traditional Chinese medicine (TCM). Bufadienolides as the major pharmacological components are generated from the venomous glands of <italic>B. bufo gargarizans</italic>. Bufadienolides are one type of cardiac aglycone with a six-member lactone ring and have properties of antitumor, cardiotonic, tonsillitis, and anti-inflammatory. The biosynthesis of bufadienolides is complex and unclear. This study explored the transcriptome of three different tissues (skin glands, venom glands, and muscles) of <italic>B. bufo gargarizans</italic> by high-throughput sequencing. According to the gene tissue–specific expression profile, 389 candidate genes were predicted possibly participating in the bufadienolides biosynthesis pathway. Then, BbgCYP11A1 was identified as a cholesterol side chain cleaving the enzyme in engineering yeast producing cholesterol. Furthermore, the catalytic activity of BbgCYP11A1 was studied with various redox partners. Interestingly, a plant NADPH-cytochrome P450 reductase (CPR) from <italic>Anemarrhena asphodeloides</italic> showed notably higher production than BbgAdx-2A-BbgAdR from <italic>B. bufo gargarizans</italic>. These results will provide certainly molecular research to reveal the bufadienolides biosynthesis pathway in <italic>B. bufo gargarizans</italic>.</p>