Bursicon mediates antimicrobial peptide gene expression to enhance crowded larval prophylactic immunity in the oriental armyworm, Mythimna separata

Copyright © 2020 Elsevier Ltd. All rights reserved..

It has been reported that a high population density alters insect prophylactic immunity. Bursicon plays a key role in the prophylactic immunity of newly emerged adults. In this paper, full-length cDNAs encoding the alpha and beta subunits of bursicon in Mythimna separata larvae (Msburs α and Msburs β) were identified. The cDNAs of Msburs α and Msburs β contain open reading frames (ORFs) encoding 145- and 139-amino acid residue proteins, respectively. Multiple alignment sequences and phylogenetic analysis indicated that Msbursicons (Msburs α and Msburs β) are orthologous to bursicons in other lepidopterans. The Msbursicons were expressed throughout all developmental states with higher relative expression during the egg, pupae, and adult stages. Msbursicons (Msburs α and Msburs β) were highly expressed in the ventral nerve cord and brain relative to other tested tissues. Msbursicon expression of larvae subject to high-density treatment (10 larvae per jar) was significantly increased compared with that of the larvae subject to low-density treatment (1 larva per jar) in the whole fourth and fifth instar stages. The trend in the expression of the antimicrobial peptide (AMP) genes cecropin C and defensin in the test stage was accorded and delayed with increased expression of bursicons. Silencing Msburs α (or Msburs β) expression by dsRNA injection in larvae subject to high-density treatment significantly decreased the expression levels of the cecropin C and defensin genes. Recombinant Msbursicon homodimers significantly induced the expression of the cecropin C and defensin genes. There was a notable decrease in the survival rate of the Msburs α (or Msburs β or Mscecropin C or Msdefensin) knockdown larvae infected by Beauveria thuringiensis. Our findings provide the first insights into how larval density mediates AMP gene expression, which subsequently affects the prophylactic immunity of insects under high-density conditions.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:115

Enthalten in:

Developmental and comparative immunology - 115(2021) vom: 21. Feb., Seite 103896

Sprache:

Englisch

Beteiligte Personen:

Kong, Hailong [VerfasserIn]
Jing, Wanghui [VerfasserIn]
Yuan, Lin [VerfasserIn]
Dong, Chuanlei [VerfasserIn]
Zheng, Minyuan [VerfasserIn]
Tian, Zhen [VerfasserIn]
Hou, Qiuli [VerfasserIn]
Cheng, Yunxia [VerfasserIn]
Zhang, Lei [VerfasserIn]
Jiang, Xingfu [VerfasserIn]
Luo, Lizhi [VerfasserIn]

Links:

Volltext

Themen:

9041-06-9
Antimicrobial Peptides
Antimicrobial peptide genes
Bursicon
Crowded larvae
Insect Proteins
Invertebrate Hormones
Journal Article
Mythimna separata
Prophylactic immunity
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 10.01.2022

Date Revised 10.01.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.dci.2020.103896

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM316447080