National Navel Orange Engineering Research Center, College of Life Sciences, Gannan Normal University, Ganzhou, China.
Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, China.
Pest Manag Sci. 2024 Feb;80(2):602-612. doi: 10.1002/ps.7787. Epub 2023 Oct 6.
Asian citrus psyllid, Diaphorina citri, is a notorious pest in the citrus industry because it transmits Candidatus Liberibacter asiaticus, which causes an uncurable, devastating disease in citrus worldwide. Serratia marcescens is widely distributed in various environments that exhibits toxic effects to many insects. To develop strategies for enhancing the efficiency of pathogen-induced host mortality, a better understanding of the toxicity mechanism of Serratia marcescens on Diaphorina citri is critical.
Serratia marcescens KH-001 successfully colonized Diaphorina citri gut by feeding artificial diets, resulting in the damage of cells including nucleus, mitochondria, vesicles, and microvilli. Oral ingestion of Serratia marcescens KH-001 strongly induced apoptosis in gut cells by enhancing levels of Cyt c, p53 and caspase-1 and decreasing levels of inhibitors of apoptosis (IAP) and Bax inhibitor-1 (BI-1). The expression of dual oxidase (Duox) and nitric oxide synthase (Nos) was up-regulated by Serratia marcescens KH-001, which increased hydrogen peroxide (H O ) levels in the gut. Injection of abdomen of Diaphorina citri with H O accelerated the death of the adults and induced apoptosis in the gut cells by activating Cyt c, p53 and caspase-1 and suppressing IAP and BI-1. Pretreatment of infected Diaphorina citri with vitamin c (Vc) increased the adult survival and diminished the apoptosis-inducing effect.
The colonization of Serratia marcescens KH-001 in the guts of Diaphorina citri increased H O accumulation, leading to severe changes and apoptosis in intestinal cells, which enhanced a higher mortality level of D. citr. This study identifies the underlying virulence mechanism of Serratia marcescens KH-001 on Diaphorina citri that contributes to a widespread application in the integrated management of citrus psyllid. © 2023 Society of Chemical Industry.
亚洲柑橘木虱，Diaphorina citri，是柑橘产业中的一种臭名昭著的害虫，因为它传播 Candidatus Liberibacter asiaticus，这种病原体在全球范围内导致柑橘无法治愈的毁灭性疾病。粘质沙雷氏菌广泛分布于各种环境中，对许多昆虫具有毒性作用。为了提高病原体诱导宿主死亡率的效率，深入了解粘质沙雷氏菌对亚洲柑橘木虱的毒性机制至关重要。
粘质沙雷氏菌 KH-001 通过喂食人工饲料成功定植于亚洲柑橘木虱肠道，导致细胞核、线粒体、小泡和微绒毛等细胞受损。口服粘质沙雷氏菌 KH-001 强烈诱导肠道细胞凋亡，通过增加 Cyt c、p53 和 caspase-1 的水平，降低凋亡抑制因子（IAP）和 Bax 抑制剂-1（BI-1）的水平。双氧化酶（Duox）和一氧化氮合酶（Nos）的表达被粘质沙雷氏菌 KH-001 上调，导致肠道中过氧化氢（H2O2）水平升高。向亚洲柑橘木虱腹部注射 H2O2 通过激活 Cyt c、p53 和 caspase-1 以及抑制 IAP 和 BI-1 加速成虫死亡并诱导肠道细胞凋亡。用维生素 C（Vc）预处理感染的亚洲柑橘木虱增加了成虫的存活率，并减弱了凋亡诱导作用。
粘质沙雷氏菌 KH-001 在亚洲柑橘木虱肠道中的定植增加了 H2O2 的积累，导致肠道细胞严重变化和凋亡，从而提高了柑橘木虱的死亡率。本研究确定了粘质沙雷氏菌 KH-001 对亚洲柑橘木虱的潜在致病机制，有助于广泛应用于柑橘木虱的综合管理。 © 2023 化学工业协会。
