Location: National Peanut Research LaboratoryTitle: Characterizing small RNA populations in non-transgenic and aflatoxin-reducing-transgenic peanut lines
Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/30/2016
Publication Date: N/A
Interpretive Summary: High-throughput sequencing was performed to compare the expression of the small RNA populations in non-transgenic and aflatoxin-reducing-transgenic peanut lines, and determine their putative involvement in aflatoxin reduction. This information will increase our understanding of the effectiveness of RNAi, and enable the possible improvement of the RNAi construct.
Technical Abstract: Aflatoxin contamination is a major constraint in the food production worlwide. In peanut these aflatoxins are mainly produced by Aspergillus flavus (Link) and A. parasiticus (Speare). The use of RNA interference (RNAi) is a promising method to reduce or prevent the accumulation of aflatoxin in peanut seed. A method to evaluate the effectiveness of RNAi is to study the profiles of small RNAs (sRNAs), in particular those derived from the RNAi construct. In this study, we performed high-throughput sequencing of small RNA populations in two peanut lines, that express an inverted repeat targeting five genes involved in the aflatoxin-biosynthesis pathway, and showed 84-100% less aflatoxin B1 than the controls, with the aim to determine their putative involvement in aflatoxin reduction. In total, 132 known and more than 300 putative novel micro RNAs (miRNAs) were identified. Among those, 23 known and four novel miRNAs were differentially expressed in the transgenic lines. We furthermore found two sRNAs derived from the inverted repeat and 94 sRNAs that were only present in the transgenic lines and that mapped without mismatches to A. flavus. This information will increase our understanding of the effectiveness of RNAi, and enable the possible improvement of the RNAi construct.