Editorial: MicroRNA: the swift development in infectious diseases 1 2 3

Sabreena Safuan ¹ Dr. Siddhartha Pati ² Hisham Atan Edinur ^1*

• ¹ Universiti Sains Malaysia Health Campus, Kota Bharu, Kelantan, Malaysia
• ² NatNov Bioscience Private Limited, Balasore, India

MicroRNAs (miRNAs) are short, non-protein-coding ribonucleic acid (RNA) molecules 14 which act as post-transcriptional regulators via binding to the 3' untranslated regions (3'-UTRs) 15 of target messenger RNAs (mRNAs) (Ratti et al., 2020). They have negative regulation of gene 16 expression, particularly by degrading target mRNA or inhibiting the translation of protein. 17 Thousands of them have been well characterised in cell growth signalling pathway, differentiation, 18 apoptosis, pathogen-host interactions, stress responses and immune function (Tribolet et al., 2020;19 Kimura et al., 2023). The discovery of miRNA as important players in gene regulation has opened 20 up a new dimension of research in molecular biology, particularly in the study of infectious 21 diseases. Therefore, this research topic aims to collect the latest advancements on the impact of 22 miRNAs on pathogen-host interactions and their potential as prognostic biomarkers and 23 therapeutic targets. 24 25 During infection, significant changes in miRNA expression can be detected as part of the 26 immune response modulation to protect the host. Pathogens could also exploit the host's miRNA 27 machinery to evade detection, suppresses immune responses and facilitate colonisation within the 28 host. In this research topic, Bostanghadiri et al. (2023) Fusobacterium nucleatum, a Gram-negative anaerobic bacterium and miRNA expression levels in 30 colorectal adenocarcinoma and matched adjacent normal tissues. They reported higher level of F. a meta-analysis with the aim to evaluate the value of miRNAs as both prognostic and diagnostic 47 biomarkers in sepsis patients. A total of 55 studies were included in the meta-analysis with miR-48 133a-3p as the highest diagnostic accuracy. Others including miR-146a, miR-21, miR-210, miR-49 223-3p, miR-155 can also be potentially used as biomarkers for predicting sepsis mortality. In 50 another review, Venkatesan et al. (2023) discussed the potential applications of exosome miRNAs 51 as diagnosis markers of vector-borne diseases. These include for malaria, schistosomiasis, 52 rickettsia, chagas and Japanese encephalitis. They also highlighted the lack of plasma exosome 53 research even though plasma-derived exosome miRNAs were shown to differentially expressed in 54 vector-borne infected hosts. 55In conclusion, the articles collected under this research topic provides important update on 56 the role of miRNA during pathogen colonisation and disease pathogenesis. Understanding miRNA 57 biogenesis and associated machinery in the context of infectious diseases is not only essential for 58 advancing our knowledge but also carries significant potential for the development of novel 59 prognostic biomarkers and therapeutic strategies. 60 61