The Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, Virginia, USA.
W. Harry Feinstone Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA.
Sci Rep. 2017 Jul 26;7(1):6493. doi: 10.1038/s41598-017-07013-1.
Drastic changes in gene expression occur after adult female mosquitoes take a blood meal and use the nutrients for egg maturation. A growing body of evidence indicates that microRNAs (miRNAs) contribute to this tightly controlled tissue- and stage-specific gene expression. To investigate the role of miRNAs, we monitored miRNA expression in the mosquito Anopheles gambiae during the 72-h period immediately after blood feeding. We also measured the association of miRNAs with Argonaute 1 (Ago1) and Argonaute 2 (Ago2) to assess the functional status of individual miRNA species. Overall, 173 mature miRNAs were precipitated with Ago1 and Ago2, including 12 new miRNAs, the orthologs of which are found thus far only in other Anopheles species. Ago1 is the predominant carrier of miRNAs in Anopheles gambiae. The abundance and Ago loading of most of the mature miRNAs were relatively stable after blood ingestion. However, miRNAs of the miR-309/286/2944 cluster were considerably upregulated after blood feeding. Injection of the specific antagomir for miR-309 resulted in smaller developing oocytes and ultimately fewer eggs. In addition, the Ago association of some miRNAs was not proportional to their cellular abundance, suggesting that integration of miRNAs into the Ago complexes is regulated by additional mechanisms.
成蚊吸血后，其基因表达会发生剧烈变化，这些变化会被用来促进卵成熟。越来越多的证据表明，microRNAs（miRNAs）有助于实现这种严格调控的组织和阶段特异性基因表达。为了研究 miRNAs 的作用，我们在吸血后 72 小时内监测了按蚊 Anopheles gambiae 中的 miRNA 表达情况。我们还测量了 miRNAs 与 Argonaute 1（Ago1）和 Argonaute 2（Ago2）的关联，以评估各个 miRNA 物种的功能状态。总的来说，用 Ago1 和 Ago2 沉淀了 173 种成熟的 miRNA，其中包括 12 种新的 miRNA，迄今为止，这些 miRNA 的同源物仅在其他按蚊物种中发现。Ago1 是按蚊中 miRNA 的主要载体。大多数成熟 miRNA 的丰度和 Ago 加载在吸血后相对稳定。然而，miR-309/286/2944 簇的 miRNA 在吸血后大量上调。注射特定的 miR-309 反义寡核苷酸会导致发育中的卵母细胞变小，最终产卵减少。此外，一些 miRNA 的 Ago 关联与其细胞丰度不成比例，这表明 miRNA 整合到 Ago 复合物中受到其他机制的调控。
