FEBS Letters

doi: 10.1002/1873-3468.14926pmid: N/A

Sprenger, Hans‐Georg; Hansen, Julia

doi: 10.1002/1873-3468.70137pmid: 40768644

What are the most challenging and rewarding aspects of starting a new laboratory? In this article, we interview Hans‐Georg‐Sprenger, who recently started his own research group “Molecular Metabolism & Energy Homeostasis” at the Max Planck Institute for Biology of Ageing in Cologne. From the first PhD student to the first experiments, and from early discoveries and troubleshooting to the first bachelor's thesis defense, the people in the laboratory are central. For Hans‐Georg Sprenger, helping others build their skills and independence is what makes mentoring so fulfilling.

Assoumou, Kevin; Papadogkonaki, Sofia; Muneta‐Arrate, Itziar; Stoeber, Miriam

doi: 10.1002/1873-3468.70081pmid: 40426025

G protein‐coupled receptors (GPCRs) constitute the largest family of human membrane proteins. GPCRs recognize diverse extracellular stimuli and activate intracellular signaling cascades that regulate key physiological processes such as neurotransmission and cardiovascular function. The controlled transport of nascent GPCRs from the endoplasmic reticulum (ER) via the Golgi apparatus to the cell surface critically determines the cellular responsiveness to incoming ligands. Here, we present a comprehensive overview of the cellular mechanisms and motif‐driven interactions with regulatory proteins that orchestrate GPCR folding, post‐translational modifications, and vesicular transport along the secretory pathway. We highlight signaling cues that can modulate the anterograde transport and specialized mechanisms that deliver biosynthetic GPCRs to dendrites and axons in neurons. Furthermore, we discuss that many disease‐causing GPCR mutants exhibit aberrant intracellular retention, which can be rescued by pharmacological strategies that stabilize misfolded GPCRs. Finally, we highlight insights into the agonist‐driven signaling of biosynthetic GPCRs in secretory organelles. This review covers the complex roles of anterograde transport in controlling GPCR function and emerging possibilities to target the underlying mechanisms in disease.

Sabatke, Bruna; Rossi, Izadora Volpato; Ramirez, Marcel I.

doi: 10.1002/1873-3468.70055pmid: 40313034

Extracellular vesicles (EVs) are critical in cell communication, transfer of biomolecules, and host‐pathogen interaction. A newly identified subset, “interaction vesicles” (iEVs), forms through host‐pathogen contact, merging membrane elements from both. These iEVs may arise through multiple mechanisms, including direct cell–cell contact, membrane contact sites, uptake and repackaging of foreign EVs, and post‐release fusion of EVs. These hybrid vesicles enable pathogens to modify host environments, aiding immune evasion and infection persistence. However, iEVs may also act in favor of the host, contributing to pathogen recognition and elimination. Advanced techniques, including proteomics and high‐resolution microscopy, are beginning to clarify their composition and fusion. Yet, isolating these hybrid EVs remains challenging. Overcoming these barriers could enhance understanding of infection mechanisms and support diagnostic and therapeutic innovation.

Marquardt, Anja; Münchhoff, Marcus S.; Krohn, Jacqueline; Palarz, Philip M.; Taft, Manuel H.; Greve, Johannes N.; Di Donato, Nataliya; Buettner, Falk F. R.; Manstein, Dietmar J.

doi: 10.1002/1873-3468.70088pmid: 40490999

Yu, Pengpeng; Wang, Ziyang; Wen, Maorong; Chen, Wei; Liang, Xin; Wang, Chunguang

doi: 10.1002/1873-3468.70105pmid: 40572011

Spastin is a microtubule‐severing enzyme and takes part in various microtubule‐based events, but its microtubule‐severing mechanism remains largely elusive. Spastin has an intrinsically unstructured microtubule‐binding domain (MTBD) N‐terminal to the AAA domain that is indispensable for the microtubule‐severing activity. By performing a series of mutagenesis studies, we find that spastin can tolerate the mutation of a small number of basic residues in the MTBD, but mutating half of the basic residues abolishes the basal and microtubule‐stimulated ATPase activities of spastin. The isolated MTBD pellets an equal molar amount of tubulin into curl and ring assemblies. Moreover, spastin with a sequence‐reversed MTBD is active in ATP hydrolysis and microtubule severing. These results suggest that the MTBD of spastin participates in microtubule severing by making electrostatic interactions with microtubule protofilaments.

Miura, Shunsuke; Misaka, Tomofumi; Sekine, Toranosuke; Ogawara, Ryo; Ichimura, Shohei; Tomita, Yusuke; Yokokawa, Tetsuro; Oikawa, Masayoshi; Ishida, Takafumi; Takeishi, Yasuchika

doi: 10.1002/1873-3468.70119pmid: 40878827

Mehta, Deepak; Joshi, Pooja; Pullarkat, Pramod

doi: 10.1002/1873-3468.70074pmid: 40490995

Oxidative stress caused by excessive reactive oxygen species adversely affects cellular function. Here, we investigate axonal beading induced by the photo‐oxidation of a membrane‐based fluorescent dye. Our experiments show that, apart from using oxygen scavengers, chelation of free calcium, or stabilization of microtubules or actin filaments by pharmacological agents can mitigate oxidative‐stress‐induced beading. Furthermore, we take advantage of this light‐induced oxidative stress to explore axonal responses to spatially confined perturbations. We demonstrate that low excitation causes localized, long‐lasting axon beading, whereas high excitation leads to widespread degeneration and beading. Besides the results presented here, this light‐based technique is a convenient tool for investigating local oxidative stress in tissues, such as brain slices or organoids.

Nakagawa, Takumi; Hata, Kosuke; Izumi, Yoshihiro; Nakashima, Hideyuki; Katada, Sayako; Matsuda, Taito; Bamba, Takeshi; Nakashima, Kinichi

doi: 10.1002/1873-3468.70067pmid: 40377017

Som, Saubhik; Vishalakshi, Gopalapura J.; Manjunath, Lekha E.; Manna, Debraj; Vasu, Kirtana; Singh, Anumeha; Siddiqua, Humaira; Eswarappa, Sandeep M.

doi: 10.1002/1873-3468.70096pmid: 40527612

Traditional in vivo studies of gene regulation often require labor‐intensive protocols and animal sacrifice. Here, we present a minimally invasive method—In Vivo Imaging of Subcutaneous Luminescence (IVISc‐L)—for analyzing gene regulation in live mice. The assay involves subcutaneous injection of plasmid DNA encoding firefly luciferase, the expression of which is controlled by the regulatory mechanism under investigation. Luminescence from the injection site is detected and quantified noninvasively using an in vivo imaging system within 24 h. We demonstrate the utility of this approach to study promoter activity, microRNA‐mediated regulation, stop codon readthrough, and rare codon effects. IVISc‐L eliminates the need for tissue extraction, offering a rapid and scalable platform for investigating gene expression dynamics and screening gene regulatory modulators in vivo.