A bacteria-regulated gut peptide determines host dependence on specific bacteria to support host juvenile development and survival

Abstract

Background Commensal microorganisms have a significant impact on the physiology of host animals, including Drosophila. Lactobacillus and Acetobacter, the two most common commensal bacteria in Drosophila, stimulate fly development and growth, but the mechanisms underlying their functional interactions remain elusive. Results We found that imaginal morphogenesis protein-Late 2 (Imp-L2), a Drosophila homolog of insulin-like growth factor binding protein 7, is expressed in gut enterocytes in a bacteria-dependent manner, determining host dependence on specific bacteria for host development. Imp-L2 mutation abolished the stimulatory effects of Lactobacillus, but not of Acetobacter, on fly larval development. The lethality of the Imp-L2 mutant markedly increased under axenic conditions, which was reversed by Acetobacter, but not Lactobacillus, re-association. The host dependence on specific bacteria was determined by Imp-L2 expressed in enterocytes, which was repressed by Acetobacter, but not Lactobacillus. Mechanistically, Lactobacillus and Acetobacter differentially affected steroid hormone-mediated Imp-L2 expression and Imp-L2-specific FOXO regulation. Conclusions Our finding may provide a way how host switches dependence between different bacterial species when benefiting from varying microbiota.

Role of gut symbionts of insect pests: A novel target for insect-pest control

“…Similarly, development of this fruit fly is also symbiont dependent. The expression of imaginal morphogenesis protein-Late 2 (Imp-L2), depends on bacteriocyte harboring Acetobacter and Lactobacilli ( Lee et al, 2022 ). Studies have shown that the symbionts harboring the gut can activate gut nerves to send signals to brain nerves ( Forsythe and Kunze, 2013 ).…”

Screening of Lactiplantibacillus plantarum 67 with Strong Adhesion to Caco-2 Cells and the Effects of Protective Agents on Its Adhesion Ability during Vacuum Freeze Drying

“…It was found that the expression of LMW PBP (Accession: F9UN64) in L. plantarum 67 was significantly downregulated in the N/C group (p < 0.05; Table 2) while being significantly upregulated in the P/N group (p < 0.05; Table 2). Therefore, upregulating the expression of related proteins in the peptidoglycan pathway by the PAs can improve the adhesion of L. plantarum 67 [50].…”

Drosophila Gut Immune Pathway Suppresses Host Development-Promoting Effects of Acetic Acid Bacteria

“…It is known that certain bacterial species from the Lactobacillus and Acetobacter genera promote fly larval development and growth especially upon undernutrition. In a GF condition, an undernourished fly larva shows stunted body growth and delayed development, which could be rescued by mono-association with specific commensal bacterial species, such as Lactobacillus plantarum (Lp) and Acetobacter pomorum (Ap) ( Erkosar et al, 2015 ; Lee et al, 2022 ; Matos et al, 2017 ; Shin et al, 2011 ; Storelli et al, 2011 ). L. plantarum exerts its beneficial effect on larval development through the host nutrient-sensing system, which depends on TORC1 activity in the adipose organ of the Drosophila and, subsequently, modulates the hormones regulating growth and maturation ( Storelli et al, 2011 ).…”