Advances in the Immune Regulatory Role of Non-Coding RNAs (miRNAs and lncRNAs) in Insect-Pathogen Interactions

Abstract

Insects are by far the most abundant and diverse living organisms on earth and are frequently prone to microbial attacks. In other to counteract and overcome microbial invasions, insects have in an evolutionary way conserved and developed immune defense mechanisms such as Toll, immune deficiency (Imd), and JAK/STAT signaling pathways leading to the expression of antimicrobial peptides. These pathways have accessory immune effector mechanisms, such as phagocytosis, encapsulation, melanization, nodulation, RNA interference (RNAi), lysis, autophagy, and apoptosis. However, pathogens evolved strategies that circumvent host immune response following infections, which may have helped insects further sophisticate their immune response mechanisms. The involvement of ncRNAs in insect immunity is undeniable, and several excellent studies or reviews have investigated and described their roles in various insects. However, the functional analyses of ncRNAs in insects upon pathogen attacks are not exhaustive as novel ncRNAs are being increasingly discovered in those organisms. This article gives an overview of the main insect signaling pathways and effector mechanisms activated by pathogen invaders and summarizes the latest findings of the immune modulation role of both insect- and pathogen-encoded ncRNAs, especially miRNAs and lncRNAs during insect–pathogen crosstalk.

The Aedes aegypti siRNA pathway mediates broad-spectrum defense against human pathogenic viruses and modulates antibacterial and antifungal defenses

“…Flies absent of VINR showed a greater susceptibility to infections with virus and bacteria [ 63 ]. Several studies and reviews have addressed and highlighted immune modulatory of miRNAs and both insect- and pathogen-derived lncRNAs that are involved in pathogen-insect cross-talk [ 64 – 69 ].…”

Analysis of Long Non-Coding RNA-Mediated Regulatory Networks of Plutella xylostella in Response to Metarhizium anisopliae Infection

“…The objective of the current research was to identify the lncRNAs that target immune-related genes. Recent studies have shown that besides mRNAs, an abundance of miRNAs and lncRNAs affect immune responses during host–pathogen interactions [ 71 , 72 ]. Our analyses identified multiple differentially expressed cis -acting lncRNAs that target crucial immune genes, such as βGRP , Toll-like receptors 3 / 6 , trypsin , transferrin , serpins, and cytochrome P450 during M. anisopliae infection.…”

LincRNA_XR209691.3 could promote Bombyx mori nucleopolyhedrovirus replication by interacting with BmHSP70

“…LncRNAs are versatile regulators that regulate gene expression in physiological, pathological, and immunological processes (Satyavathi et al, 2017). Accumulated pieces of evidence have confirmed the importance of lncRNAs in the regulation of insectpathogen interactions (Moure et al, 2022;Valanne et al, 2019;Zhang et al, 2021;Zhang, Dong, et al, 2020;Zhang, Yin, et al, 2020). With the support of the RNA sequencing technique, in B. mori, 11,810 lncRNAs have been identified based on 21 RNA-seq databases covering the fat body, silk gland, gonad, brain and Malphghian tubule tissues so far (Wu et al, 2016).…”