CAREER: Branched Amphiphilic Peptide Capsules (BAPCs) for the delivery of lethal dsRNA into invasive organisms

迫切需要新的和创新的杀虫剂来应对几个挑战，包括对当前治疗方法的抗药性，对重要物种(如传粉者)的意外伤害，以及环境破坏。一种有希望的方法是使用双链RNA(DsRNA)来扰乱昆虫的基本基因，特别是针对有害物种，而不是有益的物种。最近的研究表明，当dsRNA与纳米材料结合时，其有效性显著增加。这种结合可以防止dsRNA的过早降解，并帮助它被昆虫肠道细胞吸收。该项目旨在探索纳米材料的特定性质如何影响基于dsRNA的生物杀虫剂的性能。研究人员将使用一种由多肽组成的独特纳米材料，研究在不同环境条件下，大小、电荷和组成的变化如何影响dsRNA的吸收、昆虫存活和稳定性。这项研究的结果意义重大，因为它们促进了我们对农业用生物材料设计的理解，潜在地导致了新的安全杀虫剂的创造。此外，该项目旨在让学生参与科学，特别是那些来自历史上被排除在外的群体的学生，通过实践经验。研究小组将通过奥本大学的项目对阿拉巴马州的学生进行关于纳米材料作为杀虫剂的潜力的教育。参加这些实验的高中生将提高他们对科学的理解和兴趣，为他们参与STEM领域做出贡献。该项目由生物材料计划和既定的刺激竞争研究计划(EPSCoR)联合资助。技术总结采用虫害管理的替代策略对于应对杀虫剂抗药性、脱靶效应和环境危害带来的挑战至关重要。利用双链RNA(DsRNA)敲除昆虫中的必需基因已成为传统农药的一种有前途的替代方案。这种方法针对有害物种，而不影响有益物种，并且缺乏已知的昆虫抗性机制。最近的发现表明，dsRNA与纳米材料的结合可以通过防止过早降解和促进肠道细胞的摄取来增强其疗效。这项研究计划的主要目标是探索纳米材料的性质如何影响基于dsRNA的生物杀虫剂的致死效应。具体地说，这个项目涉及使用支化的两亲性多肽胶囊(BAPC)和dsRNA相结合。BAPC是由PI开发的一类新型生物材料，由于两个重要因素：1)BAPC仅在水中组装，2)BAPC含有4个自由赖氨酸Ɛ-氨基，pKa值在9-10.5之间，这使得它们在中性和碱性昆虫肠道中稳定。以往的数据表明，BAPC-dsRNA复合体针对卡氏拟谷盗和豌豆弯管吸虫的必需基因，导致这两个物种的高死亡率。该提议假设，通过控制BAPC的大小、电荷和组成，有可能调节：1)细胞对dsRNA的摄取和分布，以及它在中肠细胞之间的运输；2)昆虫生存；3)对环境因素的稳定性。秋季粘虫(Spotoptera Rugiperda)和棉蚜(Aphis Cotsypii)将作为检验这一假设的害虫模型。除了科学探索，该提案还具有教育目标。它试图通过K-12外联倡议，教育阿拉巴马州的学生关于纳米材料在虫害控制方面的潜力。学生将积极参与与研究相关的活动，促进STEM领域的参与。此外，这项建议旨在促进对农业用生物材料设计的基本理解，并弥合关于跨细胞作用在昆虫中肠纳米材料运输中的作用的知识空白。该项目由生物材料计划和既定的刺激竞争研究计划(EPSCoR)共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARYNew and innovative pesticides are urgently needed to address several challenges including resistance to current treatments, unintended harm to important species like pollinators, and environmental damage. One promising approach involves using double-stranded RNA (dsRNA) to disrupt essential genes in insects specifically targeting harmful species while sparing beneficial ones. Recent studies have revealed that when dsRNA is combined with nanomaterials, its effectiveness significantly increases. This combination prevents premature degradation of dsRNA and helps it get absorbed into the cells of insect guts. This project aims to explore how specific properties of nanomaterials influence the performance of dsRNA-based biopesticides. Researchers will work with a unique nanomaterial made of peptides and study how variations in size, charge, and composition impact dsRNA absorption, insect survival, and stability in different environmental conditions. The outcomes of this study are significant as they advance our understanding of designing biomaterials for agricultural use, potentially leading to the creation of new safe pesticides. Additionally, the project aims to involve students in science, especially those from historically excluded groups through hands-on experiences. The research team will educate students in Alabama about the potential of nanomaterials as pesticides through programs at Auburn University. High school students participating in these experiments will improve their understanding and interest in science contributing to their engagement in STEM fields.This project is jointly funded by the Biomaterials Program and the Established Program to Stimulate Competitive Research (EPSCoR).TECHNICAL SUMMARYAdopting alternative strategies for insect pest management is critical to counter challenges posed by pesticide resistance, off-target effects, and environmental harm. Utilizing double-stranded RNA (dsRNA) to knockdown essential genes in insects has emerged as a promising alternative to conventional pesticides. This method targets harmful species without affecting beneficial ones and lacks known insect resistance mechanisms. Recent discoveries demonstrated that association of dsRNA with nanomaterials enhances its efficacy by preventing premature degradation and facilitating uptake by gut cells. The primary objective of this research proposal is to explore how nanomaterial properties influence the lethal effects of dsRNA-based biopesticides. Specifically, this project involves using Branched Amphiphilic Peptide Capsules (BAPCs) combined with dsRNA. BAPCs are a new class of biomaterial developed by the PI that stand out in the crowded field of nanoparticle delivery systems owing to two important factors: 1) BAPCs are assembled exclusively in water, and 2) BAPCs contain four free lysine Ɛ-amino groups with pKa values between 9 and 10.5, which makes them stable in neutral and alkaline insect guts. Previous data demonstrated that BAPC-dsRNA complexes target essential genes in Tribolium castaneum and Acyrthosiphon pisum, leading to high mortality rates in both species. The proposal hypothesizes that by manipulating the size, charge, and composition of BAPCs, it's possible to regulate: 1) the cellular uptake and distribution of dsRNA, as well as its transport across midgut cells, 2) insect survival, and 3) stability against environmental elements. The fall armyworm (Spodoptera frugiperda) and the cotton aphid (Aphis gossypii) will serve as pest models for testing the hypothesis. Beyond the scientific exploration, the proposal also has educational objectives. It seeks to educate Alabama students about the potential of nanomaterials in pest control through K-12 outreach initiatives. Students will actively participate in research-related activities, promoting engagement in STEM fields. Additionally, this proposal aims to contribute to the fundamental understanding of biomaterial design for agricultural purposes and bridge knowledge gaps regarding the role of transcytosis in nanomaterial transport across insect midguts.This project is jointly funded by the Biomaterials Program and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.