Mass Spectrometry Imaging and ScRNA-seq Techniques to Explore the Biosynthetic pathways of Bufadienolides

ABSTRACT: Bufotoxin is an endogenous toxin made up of several physiologically active components that toads deploy as a defense against their natural enemies. Bufadienolides (BDS), which is isolated from bufotoxin, is an important anticancer drug, and other components such as bufotenine and alkaloids are also important drug resources. The distribution characteristics and biosynthesis of bufotoxins in the postauricular glands (PGs) of toads are not well understood. We examined the toad's PGs using the MADLI/MSI technique, a total of 1,872 components were found, and some pharmacological components were visible. These findings indicate that bufotoxins are primarily abundant in the plasma glands (pG) and epidermal tissues of the glands. By using single-cell sequencing, it was possible to create a single-cell atlas of 9316 PGs cells. These cells were then categorized into nine clusters using marker genes, and two types of epithelial cells were verified using in situ hybridization investigations. It was confirmed that cholesterol is a precursor component of BDS biosynthesis, we concentrated on the cholesterol metabolism component and postulated the primary bile acid pathway as a downstream biosynthesis pathway of BDS through transcriptomic studies of two pG and mucous glands (MG) with distinct secretory functions. Optimal and silenced genes for potential BDS synthesis pathways, toad toxin tryptamine and alkaloid biosynthesis, terpene skeleton and steroid hormones were identified by calculating the cellular coverage of genes. Our data demonstrate the metabolic mapping of bufotoxins in the PGs of the toad, and create the first single-cell atlas of PGs in the toad, providing a reference for the study of biosynthesis of natural active ingredients in animals.

INSTRUMENT(S): autoflex

ORGANISM(S): Bufo Gargarizans Andrewsi

SUBMITTER: zhang shilin  

LAB HEAD: Jihai Gao

PROVIDER: PXD057113 | Pride | 2024-11-05

REPOSITORIES: Pride