MicroRNA-Mediated Host-Pathogen Interactions Between Bombyx mori and Viruses

Abstract

MicroRNAs (miRNAs), small non-coding RNAs of about 22 nucleotides, have been reported to regulate gene expression at the posttranscriptional level and are involved in several biological processes such as immunity, development, metabolism, and host-pathogen interactions. Apart from miRNAs encoded by the host, miRNAs produced by pathogens also regulate host genes to facilitate virus replication and evasion of the host defense responses. In recent years, accumulated studies suggest that viral infections alter the host miRNAs expression profile, and both cellular and viral miRNAs may play vital roles in host-pathogen interactions. Bombyx mori, one of the critical lepidopteran model species, is an economically important insect for silk production. The mechanism of interaction between B. mori and its pathogens and their regulation by miRNAs has been extensively studied. Therefore, in this review, we aim to highlight the recent information and understanding of the virus-encoding miRNAs and their functions in modulating viral and host (B. mori) genes. Additionally, the response of B. mori derived miRNAs to viral infection is also discussed. A detailed critical view about miRNAs’ regulatory roles in B. mori-virus interactions will help us understand molecular networks and develop a sustainable antiviral strategy.

Circadian clock regulates developmental time through ecdysone and juvenile hormones in Bombyx mori

“…Bombyx mori , one of the important lepidopteran model species, is also one of the earliest insects for circadian rhythm research (Awais et al, 2021; Brady et al, 2021; Sakamoto & Shimizu, 1994; Sillans et al, 1964). In this study, knockout Cry1 silkworm exhibited an arrhythmic hatching behaviour with a dysfunctional molecular clock.…”

Nosema bombycis microRNA-like RNA 8 (Nb-milR8) Increases Fungal Pathogenicity by Modulating BmPEX16 Gene Expression in Its Host, Bombyx mori

“…4 ). Pathogenic milRNAs are generally considered necessary components for host-pathogen interactions, with milRNAs generally thought to be helpful for promoting pathogen proliferation and replication ( 8 , 17 ). For example, Vm-milRNAs adaptively regulate the virulence genes encoding sucrose nonfermenting 1 (VmSNF1), 4,5-DOPA dioxygenase extradiol (VmDODA), and a hypothetical protein (VmHy1) that enhances the virulence of V. mali in apple trees.…”

“…Increasing attention has been paid in recent years to understanding microRNAs (miRNAs) that are transcribed, but do not encode proteins, and can perform biological functions at the RNA level within pathogen-host interactions ( 8 – 10 ). miRNAs are short RNA sequences with lengths typically of 18 to 25 nucleotides (nt) and are endogenous noncoding RNAs with regulatory functions that primarily exist in eukaryotes ( 11 ).…”

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

“…The JAK/STAT pathway was originally identified as a cytokine signaling pathway in mammals ( 59 – 62 ). This pathway provides an antiviral protection ( 27 , 28 , 63 ). Unlike the Toll and Imd pathways, little is known about the transcriptional cascade induced by the JAK/STAT pathway ( 14 , 64 ).…”

“…Moreover and interestingly, the review written by Awais et al. ( 27 ) summarizes the diversity and multitude of differentially regulated miRNAs in Bombyx mori ( B. mori ) upon several viral attacks, such as B. mori cypovirus (BmCPV), B. mori nucleopolyhedrovirus (BmNPV), and B. mori Autographa californica multiple nucleopolyhedrovirus (AcMNPV). In parallel, the Drosophila melanogaster ( D. melanogaster ) lncRNA CR44404 (renamed lincRNA-IBIN) was highly induced (1300-fold) by Gram-positive or Gram-negative bacteria in Drosophila adults or a parasitoid wasp Leptopilina boulardi in Drosophila larvae ( 28 ).…”