Department of Medical Laboratory Science & Pathology, Jimma University, Jimma, Ethiopia.
Biometrics Research Group, Ghent University, Ghent, Belgium.
Parasit Vectors. 2020 Apr 19;13(1):202. doi: 10.1186/s13071-020-04078-2.
Malaria vector mosquitoes acquire midgut microbiota primarily from their habitat. The homeostasis of these microbial communities plays an essential role in the mosquito longevity, the most essential factor in the mosquito vectorial capacity. Our recent study revealed that silencing genes involved in regulation of the midgut homeostasis including FN3D1, FN3D3 and GPRGr9 reduced the survival of female adult Anopheles arabiensis mosquitoes. In the present study, we investigate the stability of the gene silencing efficiency of mosquitoes reared in three different breeding conditions representing distinct larval habitat types: town brick pits in Jimma, flood pools in the rural land of Asendabo and roadside pools in Wolkite.
First-instar larvae of An. arabiensis mosquitoes were reared separately using water collected from the three breeding sites. The resulting adult females were micro-injected with dsRNA targeting the FN3D1 gene (AARA003032) and their survival was monitored. Control mosquitoes were injected with dsRNA Lacz. In addition, the load of midgut microbiota of these mosquitoes was determined using flow cytometry.
Survival of naïve adult female mosquitoes differed between the three sites. Mosquitoes reared using water collected from brick pits and flood pools survived longer than mosquitoes reared using water collected from roadside. However, the FN3D1 gene silencing effect on survival did not differ between the three sites.
The present study revealed that the efficacy of FN3D1 gene silencing is not affected by variation in the larval habitat. Thus, silencing this gene has potential for application throughout sub-Saharan Africa.
疟疾病媒蚊主要从其栖息地获得中肠微生物群。这些微生物群落的动态平衡在蚊子寿命中起着至关重要的作用，而蚊子寿命是蚊子传播能力的最重要因素。我们最近的研究表明，沉默参与中肠动态平衡调节的基因，包括 FN3D1、FN3D3 和 GPRGr9，会降低雌性成年阿拉伯按蚊的存活率。在本研究中，我们研究了在三种不同的饲养条件下饲养的蚊子的基因沉默效率的稳定性，这三种饲养条件代表了不同的幼虫栖息地类型：吉姆马的城镇砖坑、阿桑达博农村土地的洪水坑和沃尔凯特的路边水坑。
分别使用从三个繁殖地点采集的水饲养第一龄期的阿拉伯按蚊幼虫。所得的成年雌性蚊子被微注射针对 FN3D1 基因（AARA003032）的 dsRNA，监测其存活情况。对照蚊子注射 dsRNA Lacz。此外，还使用流式细胞术确定这些蚊子中肠微生物群的负荷。
三种地点的原始成年雌性蚊子的存活率不同。使用砖坑和洪水坑收集的水饲养的蚊子比使用路边收集的水饲养的蚊子存活时间更长。然而，FN3D1 基因沉默对存活率的影响在三个地点没有差异。
本研究表明，FN3D1 基因沉默的效果不受幼虫栖息地变化的影响。因此，沉默该基因有可能在整个撒哈拉以南非洲地区得到应用。
