Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, MA 01003, USA.
Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA.
J Insect Sci. 2021 Mar 1;21(2). doi: 10.1093/jisesa/ieab015.
The salivary glands of insects play a key role in the replication cycle and vectoring of viral pathogens. Consequently, Musca domestica (L.) (Diptera: Muscidae) and the Salivary Gland Hypertrophy Virus (MdSGHV) serve as a model to study insect vectoring of viruses. A better understanding of the structural changes of the salivary glands by the virus will help obtain a better picture of the pathological impact the virus has on adult flies. The salivary glands are a primary route for viruses to enter a new host. As such, studying the viral effect on the salivary glands is particularly important and can provide insights for the development of strategies to control the transmission of vector-borne diseases, such as dengue, malaria, Zika, and chikungunya virus. Using scanning and transmission electron microscopic techniques, researchers have shown the effects of infection by MdSGHV on the salivary glands; however, the exact location where the infection was found is unclear. For this reason, this study did a close examination of the effects of the hypertrophy virus on the salivary glands to locate the specific sites of infection. Here, we report that hypertrophy is present mainly in the secretory region, while other regions appeared unaffected. Moreover, there is a disruption of the cuticular, chitinous lining that separates the secretory cells from the lumen of the internal duct, and the disturbance of this lining makes it possible for the virus to enter the lumen. Thus, we report that the chitinous lining acts as an exit barrier of the salivary gland.
昆虫的唾液腺在病毒的复制周期和载体传播中起着关键作用。因此，家蝇（Musca domestica）（双翅目：蝇科）和唾液腺增生病毒（MdSGHV）被用作研究昆虫传播病毒的模型。更好地了解病毒对唾液腺的结构变化将有助于更好地了解病毒对成年苍蝇的病理影响。唾液腺是病毒进入新宿主的主要途径。因此，研究病毒对唾液腺的影响尤为重要，这可以为开发控制蚊媒疾病传播的策略提供思路，例如登革热、疟疾、寨卡病毒和基孔肯雅热病毒。研究人员使用扫描和透射电子显微镜技术研究了 MdSGHV 感染对唾液腺的影响；然而，尚不清楚确切的感染部位。出于这个原因，本研究对肥大病毒对唾液腺的影响进行了仔细检查，以确定感染的具体部位。在这里，我们报告说，肥大主要发生在分泌区，而其他区域似乎没有受到影响。此外，分泌细胞与内部管腔之间的角质、几丁质衬里被破坏，这种衬里的破坏使得病毒能够进入管腔。因此，我们报告说，几丁质衬里是唾液腺的出口屏障。
