Keshavarz Maryam, Jo Yong Hun, Edosa Tariku Tesfaye, Han Yeon Soo
Department of Applied Biology, College of Agriculture and Life Sciences, Institute of Environmentally-Friendly Agriculture (IEFA), Chonnam National University, Gwangju, South Korea.
Front Physiol. 2020 Apr 15;11:320. doi: 10.3389/fphys.2020.00320. eCollection 2020.
Invading pathogens are recognized by peptidoglycan recognition proteins (PGRPs) that induce translocation of NF-κB transcription proteins and expression of robust antimicrobial peptides (AMPs). PGRP-LE (PGRP-LE) has been previously identified as a key sensor of infection. Here, we present that is highly expressed in the gut of larvae and 5-day-old adults in the absence of microbial infection. In response to and infections, mRNA levels are significantly upregulated in both the fat body and gut. Silencing of by RNAi rendered significantly more susceptible to challenge by infection and, to a lesser extent, and infections. Reduction of levels in the larval gut resulted in downregulation of eight AMP genes following exposure to , , and . However, the transcriptional levels of AMPs more rapidly reached a higher level in the ds-treated larval gut after challenge with , which may suggest that AMPs induction were more sensitive to than and In addition, RNAi following and challenges had notable effects on , isoform (), and expression level in the fat body and gut. Taken together, acts as an important gut microbial sensor that induces AMPs via Imd activation in response to , whereas involvement of in AMPs synthesize is barely perceptible in the hemocytes and fat body.
入侵病原体被肽聚糖识别蛋白（PGRPs）识别，这些蛋白可诱导NF-κB转录蛋白的转位并表达强大的抗菌肽（AMPs）。PGRP-LE（PGRP-LE）先前已被确定为感染的关键传感器。在此，我们发现其在未受微生物感染的幼虫肠道和5日龄成虫中高度表达。响应于和感染，脂肪体和肠道中的mRNA水平均显著上调。通过RNAi沉默使对感染的挑战更敏感，在较小程度上对和感染也更敏感。幼虫肠道中水平的降低导致在暴露于、和后八个AMP基因的下调。然而，在用攻击后，ds处理的幼虫肠道中AMPs的转录水平更快地达到更高水平，这可能表明AMPs的诱导对比和更敏感。此外，在和攻击后进行RNAi对脂肪体和肠道中的、异构体（）和表达水平有显著影响。综上所述，作为一种重要的肠道微生物传感器，通过响应于激活Imd来诱导AMPs，而在血细胞和脂肪体中，在AMPs合成中的参与几乎难以察觉。
