Transcriptome sequencing analysis of the MSDIN gene family encoding cyclic peptides in lethal Amanita fuligineoides. (August 2020)

• Record Type: Journal Article
• Authors: He, Yong; Zhang, Cheng-hua; Deng, Wang-qiu; Zhou, Xiao-yun; Li, Tai-hui; Li, Chuan-hua
• Is Part Of: Toxicon. Volume 183(2020)
• Page Start: 61
• Page End: 68
• Publication Date: 2020-08
• Subjects: Lethal Amanita -- Core peptide -- Phylogenetic tree -- MSDIN gene Family; Toxins -- Periodicals; Venom -- Periodicals; 615.9
• DOI: 10.1016/j.toxicon.2020.05.015
• Languages: English
• ISSNs: 0041-0101

Abstract

Abstract: Amanita fuligineoides, a lethal mushroom discovered in China, contains abundant cyclic peptide toxins that can cause fatal poisoning. However, the MSDIN gene family encoding for these cyclic peptides in A. fuligineoides has not been systematically studied. In this research, the transcriptome sequencing of A. fuligineoides was performed and its MSDIN family members were analyzed. A total of 4.41 Gb data containing 30833 unigenes was obtained; sequence alignments throughout several databases were done to obtain their functional annotations. Based on these annotations, MSDIN genes were found and verified by RT-PCR. A total of 29 different core peptides were obtained: 3 toxin genes, encoding β-amanitin (β-AMA), phalloidin (PHD), and phallacidin (PCD), and 26 genes encoding unknown cyclic peptides, 20 of which are reported for the first time and may encode for novel cyclic peptides. Analysis of the predicted precursor peptides indicated that octocyclic peptides were the main MSDIN peptides synthesized by A. fuligineoides, accounting for the 45%. A phylogenetic analysis suggested that studied precursor peptides could be clustered into 7 clades, which might represent different functionalities. Results suggested that A. fuligineoides might have a strong capacity to synthesize cyclopeptides, laying the foundation for their excavation and utilization. Highlights: 30833 unigenes were obtained from transcriptome of lethal Amanita fuligineoides. 29 cyclopeptide genes were discovered, including 20 novel cyclopeptide genes. Octapeptide was the main cyclopeptides in Amanita fuligineoides. Two novel cyclopeptides of phallotoxins were predicted.