Modified Nucleoside Structure-Function Relations: Antiviral peptide function

约有3000万至4000万人携带人类免疫缺陷病毒(HIV)。其他逆转录病毒造成了更多的感染，新出现的传染病正在上升。不幸的是，抗逆转录病毒耐药性是在药物暴露的选择性压力下产生的。疫苗的开发一直存在问题。逆转录病毒感染干预的一个新的、有效的靶点是病毒对特定宿主细胞转移RNA(TRNA)的招募的依赖。宿主tRNA被病毒蛋白招募到新的病毒颗粒中。当病毒感染下一个细胞时，这种tRNA成为通过反转录复制其RNA基因组的引子。最近，从大量的多肽文库中选择了15和16个氨基酸组成的小蛋白，因为它们能够与HIV招募的人类tRNA tRNALys3和其他慢病毒特异性结合，用于启动逆转录。因此，这些多肽在其对tRNALys3的特异性上模拟了HIV病毒蛋白。该计划的长期目标是了解和利用HIV对人类tRNALys 3的专门招募，并开发多肽作为工具来设计将抑制这种招募的新的小分子疗法，并将多肽本身作为推定的疗法。这个 修订项目的实验特定目标是：1)这些多肽与人tRNALys3(ASLLys3)的反密码子结构域结合，具有HIV蛋白在体内招募tRNA的高亲和力和特异性特征。来自20个具有最高亲和力和特异性的多肽的RNA结合特性将被详细描述。2)多肽的亲和力和特异性将与一个或多个参与tRNALys3招募的HIV蛋白竞争。使用电喷雾电离傅立叶变换离子回旋共振质谱仪、凝胶迁移率漂移和荧光，将确定这些多肽模拟参与招募tRNALys3的HIV蛋白的能力。由于这两个特定的目的，HIV蛋白/htRNALys3的相互作用将被阐明，多肽将被 作为研究病毒复制关键的病毒蛋白/宿主细胞RNA相互作用的成熟工具而开发。所发现的多肽可能是治疗和/或开发小型候选药物的工具的前体。

Some 30-40 million people are living with Human immunodeficiency virus, HIV. Other retroviruses account for many more infections, and emerging infectious diseases are on the rise. Unfortunately, antiretroviral resistance develops in the presence of the selective pressure of drug exposure. Vaccine development has been problematic. A novel, validated target of intervention for retrovirus infection is the virus' dependence on the recruitment of a specific host cell transfer RNA (tRNA). The host tRNA is recruited by viral proteins into the new viral particles. When the virus infects the very next cell, this tRNA becomes the primer for replication of its RNA genome through reverse transcription. Recently, small proteins, peptides of 15 and 16 amino acids, have been selected from vast libraries of peptides for their abilities to bind specifically the one human tRNA, tRNALys3, that is recruited by HIV, and other lentiviruses for priming reverse transcription. Thus, the peptides mimic HIV viral proteins in their specificity for tRNALys3. The long-term objectives of this program are to understand and exploit the dedicated recruitment of human tRNALys3 by HIV, and to develop peptides as tools for designing new small molecule therapeutics that will inhibit the recruitment, and the peptides themselves as putative therapeutics. The experimental specific aims of the revised project are: 1) The peptides bind the anticodon domain of human tRNALys3 (ASLLys3) with high affinity and specificity characteristic of HIV proteins that recruit the tRNA in vivo. The RNA binding properties of those peptides from 20 that have the highest affinities and specificities will be characterized in detail. 2) Peptide affinity and specificity will compete with one or more of the HIV proteins involved in the recruitment of tRNALys3. Using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, gel mobility shifts, and fluorescence the abilities of the peptides to mimic HIV proteins involved in recruiting the tRNALys3 will be determined. As a result of the two Specific Aims, the HIV protein/htRNALys3 interaction will be elucidated, and peptides will have been developed as proven tools for investigating viral protein/host cell RNA interactions that are critical to virus replication. The discovered peptides could be progenitors of therapeutics and/or tools in the development of small candidate drugs.