Evolutionary trend of bovine β-defensin proteins toward functionality prediction: A domain-based bioinformatics study

Natural Human Antimicrobial Peptides and Female Reproductive Tract Infections

Female reproductive tract infections (RTIs) are a major health challenge worldwide and are the leading cause of infertility and adverse pregnancy outcomes. The rising incidence of RTIs highlights their status as a major public health issue. Microbial dysbiosis, particularly bacterial, fungal, and viral infections, constitutes the primary etiological factor disrupting female reproductive health. Antimicrobial peptides (AMPs) are evolutionarily conserved host defense molecules that exhibit broad-spectrum antimicrobial activity against pathogens, as well as anti-inflammatory and immunomodulatory properties. This review systematically summarizes the structural diversity, biological sources, and mechanistic pathways of human-derived AMPs in combating RTIs, with a particular emphasis on their therapeutic potential in fertility preservation. Emerging evidence suggests AMPs as promising alternatives to conventional antibiotics in the post-antibiotic era.

Paving the way for new antimicrobial peptides through molecular de-extinction

Molecular de-extinction has emerged as a novel strategy for studying biological molecules throughout evolutionary history. Among the myriad possibilities offered by ancient genomes and proteomes, antimicrobial peptides (AMPs) stand out as particularly promising alternatives to traditional antibiotics. Various strategies, including software tools and advanced deep learning models, have been used to mine these host defense peptides. For example, computational analysis of disulfide bond patterns has led to the identification of six previously uncharacterized β-defensins in extinct and critically endangered species. Additionally, artificial intelligence and machine learning have been utilized to uncover ancient antibiotics, revealing numerous candidates, including mammuthusin, and elephasin, which display inhibitory effects toward pathogens in vitro and in vivo. These innovations promise to discover novel antibiotics and deepen our insight into evolutionary processes.

Antimicrobial Peptides Against Arboviruses: Mechanisms, Challenges, and Future Directions

This review delves into the potential of antimicrobial peptides (AMPs) as promising candidates for combating arboviruses, focusing on their mechanisms of antiviral activity, challenges, and future directions. AMPs have shown promise in preventing arbovirus attachment to host cells, inducing interferon production, and targeting multiple viral stages, illustrating their multifaceted impact on arbovirus infections. Structural elucidation of AMP-viral complexes is explored to deepen the understanding of molecular determinants governing viral neutralization, paving the way for structure-guided design. Furthermore, this review highlights the potential of AMP-based combination therapies to create synergistic effects that enhance overall treatment outcomes while minimizing the likelihood of resistance development. Challenges such as susceptibility to proteases, toxicity, and scalable production are discussed alongside strategies to address these limitations. Additionally, the expanding applications of AMPs as vaccine adjuvants and antiviral delivery systems are emphasized, underscoring their versatility beyond direct antiviral functions.

Insights into trait-association of selection signatures and adaptive eQTL in indigenous African cattle

BACKGROUND

African cattle represent a unique resource of genetic diversity in response to adaptation to numerous environmental challenges. Characterising the genetic landscape of indigenous African cattle and identifying genomic regions and genes of functional importance can contribute to targeted breeding and tackle the loss of genetic diversity. However, pinpointing the adaptive variant and determining underlying functional mechanisms of adaptation remains challenging.

RESULTS

In this study, we use selection signatures from whole-genome sequence data of eight indigenous African cattle breeds in combination with gene expression and quantitative trait loci (QTL) databases to characterise genomic targets of artificial selection and environmental adaptation and to identify the underlying functional candidate genes. In general, the trait-association analyses of selection signatures suggest the innate and adaptive immune system and production traits as important selection targets. For example, a large genomic region, with selection signatures identified for all breeds except N'Dama, was located on BTA27, including multiple defensin DEFB coding-genes. Out of 22 analysed tissues, genes under putative selection were significantly enriched for those overexpressed in adipose tissue, blood, lung, testis and uterus. Our results further suggest that cis-eQTL are themselves selection targets; for most tissues, we found a positive correlation between allele frequency differences and cis-eQTL effect size, suggesting that positive selection acts directly on regulatory variants.

CONCLUSIONS

By combining selection signatures with information on gene expression and QTL, we were able to reveal compelling candidate selection targets that did not stand out from selection signature results alone (e.g. GIMAP8 for tick resistance and NDUFS3 for heat adaptation). Insights from this study will help to inform breeding and maintain diversity of locally adapted, and hence important, breeds.

Defensins: A novel weapon against Mycobacterium tuberculosis?

Tuberculosis (TB) is a serious airborne communicable disease caused by organisms of the Mycobacterium tuberculosis (Mtb) complex. Although the standard treatment antimicrobials, including isoniazid, rifampicin, pyrazinamide, and ethambutol, have made great progress in the treatment of TB, problems including the rising incidence of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB), the severe toxicity and side effects of antimicrobials, and the low immunity of TB patients have become the bottlenecks of the current TB treatments. Therefore, both safe and effective new strategies to prevent and treat TB have become a top priority. As a subfamily of cationic antimicrobial peptides, defensins are rich in cysteine and play a vital role in resisting the invasion of microorganisms and regulating the immune response. Inspired by studies on the roles of defensins in host defence, we describe their research history and then review their structural features and antimicrobial mechanisms, specifically for fighting Mtb in detail. Finally, we discuss the clinical relevance, therapeutic potential, and potential challenges of defensins in anti-TB therapy. We further debate the possible solutions of the current application of defensins to provide new insights for eliminating Mtb.