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Abstract Proximity ligation assays (PLAs) use specific antibodies to detect endogenous protein‐protein interactions. PLAs are a highly useful biochemical technique that allow two proteins within proximity to be visualized with fluorescent probes amplified by PCR. While this technique has gained prominence, the use of a PLA in mouse skeletal muscle (SkM) is novel. In this article, we discuss how the PLA method can be used in SkM to study the protein‐protein interactions within mitochondria‐endoplasmic reticulum contact sites (MERCs). © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Proximity ligation assay for skeletal muscle tissue and myoblast for MERC proteins 

Abstract OPA1 is a dynamin‐related GTPase that modulates mitochondrial dynamics and cristae integrity. Humans carry eight different isoforms of OPA1 and mice carry five, all of which are expressed as short‐ or long‐form isoforms. These isoforms contribute to OPA1's ability to control mitochondrial energetics and DNA maintenance. However, western blot isolation of all long and short isoforms of OPA1 can be difficult. To address this issue, we developed an optimized western blot protocol based on improving running time to isolate five different isoforms of OPA1 in mouse cells and tissues. This protocol can be applied to study changes in mitochondrial structure and function. © 2025 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Western Blot Protocol for Isolating OPA1 Isoforms in Mouse Primary Skeletal Muscle Cells 

Abstract A first‐generation college student is typically defined as a student whose biological parent(s) or guardian(s) never attended college or who started but did not finish college. However, “first‐generation” can represent diverse family education situations. The first‐generation student community is a multifaceted, and intersectional group of individuals who frequently lack educational/financial resources to succeed and, consequently, require supportive environments with rigorous mentorship. However, first‐generation students often do not make their identity as first‐generation students known to others due to several psychosocial and academic factors. Therefore, they are often “invisible minorities” in higher education. In this paper, we describe the diverse family situations of first‐generation students, further define “first‐generation,” and suggest five actions that first‐generation trainees at the undergraduate/graduate stages can engage in to succeed in an academic climate. We also provide suggestions for mentors to accommodate first‐generation students' unique experiences and equip them with tools to deliver intentional mentoring practices. We hope that this paper will help promote first‐generation student success throughout the academic pipeline. 

Abstract The physical characteristics of brown adipose tissue (BAT) are defined by the presence of multilocular lipid droplets (LDs) within the brown adipocytes and a high abundance of iron‐containing mitochondria, which give it its characteristic color. Normal mitochondrial function is, in part, regulated by organelle‐to‐organelle contacts. For example, the contact sites that mediate mitochondria–LD interactions are thought to have various physiological roles, such as the synthesis and metabolism of lipids. Aging is associated with mitochondrial dysfunction, and previous studies show that there are changes in mitochondrial structure and the proteins that modulate organelle contact sites. However, how mitochondria–LD interactions change with aging has yet to be fully clarified. Therefore, we sought to define age‐related changes in LD morphology and mitochondria–lipid interactions in BAT. We examined the three‐dimensional morphology of mitochondria and LDs in young (3‐month) and aged (2‐year) murine BAT using serial block face‐scanning electron microscopy and the Amira program for segmentation, analysis, and quantification. Our analyses showed reductions in LD volume, area, and perimeter in aged samples in comparison to young samples. Additionally, we observed changes in LD appearance and type in aged samples compared to young samples. Notably, we found differences in mitochondrial interactions with LDs, which could implicate that these contacts may be important for energetics in aging. Upon further investigation, we also found changes in mitochondrial and cristae structure for the mitochondria interacting with LDs. Overall, these data define the nature of LD morphology and organelle–organelle contacts during aging and provide insight into LD contact site changes that interconnect biogerontology with mitochondrial function, metabolism, and bioactivity in aged BAT. 

Abstract Machine learning has proven useful in analyzing complex biological data and has greatly influenced the course of research in structural biology and precision medicine. Deep neural network models oftentimes fail to predict the structure of complex proteins and are heavily dependent on experimentally determined structures for their training and validation. Single‐particle cryogenic electron microscopy (cryoEM) is also advancing the understanding of biology and will be needed to complement these models by continuously supplying high‐quality experimentally validated structures for improvements in prediction quality. In this perspective, the significance of structure prediction methods is highlighted, but the authors also ask, what if these programs cannot accurately predict a protein structure important for preventing disease? The role of cryoEM is discussed to help fill the gaps left by artificial intelligence predictive models in resolving targetable proteins and protein complexes that will pave the way for personalized therapeutics. 

Abstract Disability remains an underacknowledged and underdiscussed topic in science, technology, engineering, mathematics, and medicine (STEMM). Social stigma and fear of negative outcomes have resulted in a consistent lack of disclosure. Disabilities cause social and professional difficulties for those that have them. While some faculty can be allies, past literature shows that steps must be taken to make disabilities visible in STEMM at both student and faculty levels. Here, we offer suggestions to better support faculty and students in enhancing the outcomes of individuals who have invisible disabilities. Critically, techniques such as abolishing stigma, universal learning, and better mentoring may improve the challenges faced by those who self-identify as an individual with a disability. 

Abstract Alzheimer’s Disease (AD) is a global health issue, affecting over 6 million in the United States, with that number expected to increase as the aging population grows. As a neurodegenerative disorder that affects memory and cognitive functions, it is well established that AD is associated with cardiovascular risk factors beyond only cerebral decline. However, the study of cerebrovascular techniques for AD is still evolving. Here, we provide reproducible methods to measure impedance-based pulse wave velocity (PWV), a marker of arterial stiffness, in the systemic vascular (aortic PWV) and in the cerebral vascular (cerebral PWV) systems. Using aortic impedance and this relatively novel technique of cerebral impedance to comprehensively describe the systemic vascular and the cerebral vascular systems, we examined the sex-dependent differences in 5x transgenic mice (5XFAD) with AD under normal and high-fat diet, and in wild-type mice under a normal diet. Additionally, we validated our method for measuring cerebrovascular impedance in a model of induced stress in 5XFAD. Together, our results show that sex and diet differences in wildtype and 5XFAD mice account for very minimal differences in cerebral impedance. Interestingly, 5XFAD, and not wildtype, male mice on a chow diet show higher cerebral impedance, suggesting pathological differences. Opposingly, when we subjected 5XFAD mice to stress, we found that females showed elevated cerebral impedance. Using this validated method of measuring impedance-based aortic and cerebral PWV, future research may explore the effects of modifying factors including age, chronic diet, and acute stress, which may mediate cardiovascular risk in AD. New and NoteworthyHere, we presented a new technique which is an application of the concept of aortic impedance to determining cerebral impedance. While aortic PWV is typically utilized to study aortic stiffness, we also developed a technique of cerebral PWV to study cerebral vascular stiffness. This method may be useful in improving the rigor of studies that seek to have a dual focus on cardiovascular and cerebral function.