Riboswitches are structured non-coding RNAs found in the 5′ UTR of important genes for bacterial metabolism, virulence and survival. Upon the binding of specific ligands that can vary from simple ions to complex molecules such as nucleotides and tRNAs, riboswitches change their local and global mRNA conformations to affect downstream transcription or translation. Due to their dynamic nature and central regulatory role in bacterial metabolism, riboswitches have been exploited as novel RNA-based targets for the development of new generation antibacterials that can overcome drug-resistance problems. During recent years, several important riboswitch structures from many bacterial representatives, including several prominent human pathogens, have shown that riboswitches are ideal RNA targets for new compounds that can interfere with their structure and function, exhibiting much reduced resistance over time. Most interestingly, mainstream antibiotics that target the ribosome have been shown to effectively modulate the regulatory behavior and capacity of several riboswitches, both in vivo and in vitro, emphasizing the need for more in-depth studies and biological evaluation of new antibiotics. Herein, we summarize the currently known compounds that target several main riboswitches and discuss the role of mainstream antibiotics as modulators of T-box riboswitches, in the dawn of an era of novel inhibitors that target important bacterial regulatory RNAs.

Atopic dermatitis (AD) or atopic eczema is an increasingly manifested inflammatory skin disorder of complex etiology which is modulated by both extrinsic and intrinsic factors. The exposome includes a person’s lifetime exposures and their effects. We recently reviewed the extrinsic exposome’s environmental risk factors that contribute to AD. The periods of pregnancy, infancy, and teenage years are recognized as crucial stages in the formation of AD, where the exposome leads to enduring impacts on the immune system. However, research is now focusing on the interactions between intrinsic pathways that are modulated by the extrinsic exposome, including genetic variation, epigenetic modifications, and signals, such as diet, stress, and microbiome interactions. As a result, immune dysregulation, barrier dysfunction, hormonal fluctuations, and skin microbiome dysbiosis are important factors contributing to AD development, and their in-depth understanding is crucial not only for AD treatment but also for similar inflammatory disorders.

Vault particles (VPs) are highly conserved large ribonucleoprotein complexes found exclusively in eukaryotes. They play critical roles in various cellular processes, but their involvement in cancer progression and multidrug resistance (MDR) is the most extensively studied. VPs are composed of the major vault protein (MVP), vault RNAs (vtRNAs), vault poly (ADP-ribose) polymerase, and telomerase-associated protein-1. These components are involved in the regulation of signaling pathways that affect tumor survival, proliferation, and metastasis. MVP has been associated with aggressive tumor phenotypes, while vtRNAs modulate cell proliferation, apoptosis, and autophagy. VPs also contribute to MDR by sequestering chemotherapeutic agents, altering their accumulation in the nucleus, and regulating lysosomal dynamics. Furthermore, small vault RNA-derived fragments participate in gene silencing and intercellular communication, reinforcing the role of precursors of vtRNAs in cancer development. Beyond their biological roles, VPs present a promising platform for drug delivery, due to their unique ability to encapsulate a wide range of biomolecules and therapeutic agents, followed by controlled release. This review compiles data from PubMed and Scopus, with a literature search conducted up until December 2024, highlighting current knowledge regarding VPs and their crucial involvement in cancer-related mechanisms and their applications in overcoming cancer drug resistance.

Background: Melanoma, one of the most aggressive forms of skin cancer, has seen significant therapeutic advances with immune checkpoint inhibitors (ICIs). However, many patients fail to respond or develop resistance, creating the need for adjunct strategies. Objective: The objective of this study is to critically evaluate how specific dietary patterns and nutrient-derived metabolites modulate melanoma metabolism and immunotherapy outcomes, emphasizing translational implications. Methods: We performed an integrative review of preclinical and clinical studies investigating dietary interventions in melanoma models and ICI-treated patients. Mechanistic insights were extracted from studies on nutrient transport, immunometabolism, and microbiome–immune interactions, including data from ongoing nutritional clinical trials. Results: Diets rich in fermentable fibers, plant polyphenols, and unsaturated lipids, such as Mediterranean and ketogenic diets, seem to contribute to the reprogramming of tumor metabolism and enhance CD8+ T-cell activity. Fasting-mimicking and methionine-restricted diets modulate T-cell fitness and tumor vulnerability via nutrient stress sensors (e.g., UPR, mTOR). High fiber intake correlates with favorable gut microbiota and improved ICI efficacy, while excess protein, methionine, or refined carbohydrates impair immune surveillance via lactate accumulation and immunosuppressive myeloid recruitment. Several dietary molecules act as network-level modulators of host and microbial proteins, with parallels to known drug scaffolds. Conclusions: Integrating dietary interventions into melanoma immunotherapy can significantly influence metabolic reprogramming by targeting metabolic vulnerabilities and reshaping the tumor–immune–microbiome axis. When combined with AI-driven nutrient–protein interaction mapping, this approach offers a precision nutrition paradigm that supports both physicians and patients, emerging as a novel layer to enhance and consolidate existing therapeutic strategies.

Ribonuclease Z enzymes remove 3′ trailers from precursor tRNAs. In human cells, ELAC2/RNase Z ^L matures nuclear and mitochondrial pre-tRNAs, whereas the cytosolic short paralog ELAC1/RNase Z ^S repairs ANKZF1-cleaved tRNAs, but its broader substrate repertoire remains unclear. We investigated ELAC1 function using transcriptome profiling, small RNA sequencing, CLIP-seq, and biochemical reconstitution. ELAC1 was dispensable for canonical tRNA processing but associated with structured RNA polymerase III transcripts, prominently Y RNAs and vault RNAs (vtRNAs). Purified ELAC1 cleaved all four human vtRNAs near their 3′ ends, with high-resolution mapping identifying a conserved cleavage position within the 3′ extension. Efficient cleavage required structural features of the vtRNA terminal region. In contrast, ELAC2 showed little or no vtRNA cleavage under the conditions tested and displayed stricter substrate and cleavage-site selection on pre-tRNA. Loss and re-expression of ELAC1 altered structured ncRNA abundance and small-RNA end profiles. These findings identify vtRNAs as direct ELAC1 substrates and support functional specialization of human ELAC paralogs, with ELAC2 favoring precise pre-tRNA maturation and ELAC1 exhibiting broader RNA substrate specificity.