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Abstract Qualifying exams and thesis committees are crucial components of a PhD candidate's journey. However, many candidates have trouble navigating these milestones and knowing what to expect. This article provides advice on meeting the requirements of the qualifying exam, understanding its format and components, choosing effective preparation strategies, retaking the qualifying exam, if necessary, and selecting a thesis committee, all while maintaining one's mental health. This comprehensive guide addresses components of the graduate school process that are often neglected. 

Abstract While some established undergraduate summer programs are effective across many institutions, these programs may only be available to some principal investigators or may not fully address the diverse needs of incoming undergraduates. This article outlines a 10‐week science, technology, engineering, mathematics, and medicine (STEMM) education program designed to prepare undergraduate students for graduate school through a unique model incorporating mentoring dyads and triads, cultural exchanges, and diverse activities while emphasizing critical thinking, research skills, and cultural sensitivity. Specifically, we offer a straightforward and adaptable guide that we have used for mentoring undergraduate students in a laboratory focused on mitochondria and microscopy, but which may be customized for other disciplines. Key components include self‐guided projects, journal clubs, various weekly activities such as mindfulness training and laboratory techniques, and a focus on individual and cultural expression. Beyond this unique format, this 10‐week program also seeks to offer an intensive research program that emulates graduate‐level experiences, offering an immersive environment for personal and professional development, which has led to numerous achievements for past students, including publications and award‐winning posters. 

ABSTRACT Age‐related skeletal muscle atrophy, known as sarcopenia, is characterized by loss of muscle mass, strength, endurance, and oxidative capacity. Although exercise has been shown to mitigate sarcopenia, the underlying governing mechanisms are poorly understood. Mitochondrial dysfunction is implicated in aging and sarcopenia; however, few studies explore how mitochondrial structure contributes to this dysfunction. In this study, we sought to understand how aging impacts mitochondrial three‐dimensional (3D) structure and its regulators in skeletal muscle. We hypothesized that aging leads to remodeling of mitochondrial 3D architecture permissive to dysfunction and is ameliorated by exercise. Using serial block‐face scanning electron microscopy (SBF‐SEM) and Amira software, mitochondrial 3D reconstructions from patient biopsies were generated and analyzed. Across five human cohorts, we correlate differences in magnetic resonance imaging, mitochondria 3D structure, exercise parameters, and plasma immune markers between young (under 50 years) and old (over 50 years) individuals. We found that mitochondria are less spherical and more complex, indicating age‐related declines in contact site capacity. Additionally, aged samples showed a larger volume phenotype in both female and male humans, indicating potential mitochondrial swelling. Concomitantly, muscle area, exercise capacity, and mitochondrial dynamic proteins showed age‐related losses. Exercise stimulation restored mitofusin 2 (MFN2), one such of these mitochondrial dynamic proteins, which we show is required for the integrity of mitochondrial structure. Furthermore, we show that this pathway is evolutionarily conserved, as Marf, the MFN2 ortholog inDrosophila, knockdown alters mitochondrial morphology and leads to the downregulation of genes regulating mitochondrial processes. Our results define age‐related structural changes in mitochondria and further suggest that exercise may mitigate age‐related structural decline through modulation of mitofusin 2. 

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 The kidney filters nutrient waste and bodily fluids from the bloodstream, in addition to secondary functions of metabolism and hormone secretion, requiring an astonishing amount of energy to maintain its functions. In kidney cells, mitochondria produce adenosine triphosphate (ATP) and help maintain kidney function. Due to aging, the efficiency of kidney functions begins to decrease. Dysfunction in mitochondria and cristae, the inner folds of mitochondria, is a hallmark of aging. Therefore, age-related kidney function decline could be due to changes in mitochondrial ultrastructure, increased reactive oxygen species (ROS), and subsequent alterations in metabolism and lipid composition. We sought to understand if there is altered mitochondrial ultrastructure, as marked by 3D morphological changes, across time in tubular kidney cells. Serial block facing-scanning electron microscope (SBF-SEM) and manual segmentation using the Amira software were used to visualize murine kidney samples during the aging process at 3 months (young) and 2 years (old). We found that 2-year mitochondria are more fragmented, compared to the 3-month, with many uniquely shaped mitochondria observed across aging, concomitant with shifts in ROS, metabolomics, and lipid homeostasis. Furthermore, we show that the mitochondrial contact site and cristae organizing system (MICOS) complex is impaired in the kidney due to aging. Disruption of the MICOS complex shows altered mitochondrial calcium uptake and calcium retention capacity, as well as generation of oxidative stress. We found significant, detrimental structural changes to aged kidney tubule mitochondria suggesting a potential mechanism underlying why kidney diseases occur more readily with age. We hypothesize that disruption in the MICOS complex further exacerbates mitochondrial dysfunction, creating a vicious cycle of mitochondrial degradation and oxidative stress, thus impacting kidney health. Translational StatementDue to aging, the efficiency of kidney functions begins to decrease and the risk of kidney diseases may increase, but specific regulators of mitochondrial age-related changes are poorly explained. This study demonstrates the MICOS complex may be a target for mitigating age-related changes in mitochondria. The MICOS complex can be associated with oxidative stress and calcium dysregulation, which also arise in many kidney pathologies. Graphical AbstractKidney aging causes a decline in the MICOS complex, concomitant with metabolic, lipidomic, and mitochondrial structural alterations. 

This article shows how mitochondria in murine cardiac changes, importantly elucidating age-related changes. It also is the first to show that the MICOS complex may play a role in outer membrane mitochondrial structure. 

Abstract During aging, muscle gradually undergoes sarcopenia, the loss of function associated with loss of mass, strength, endurance, and oxidative capacity. However, the 3D structural alterations of mitochondria associated with aging in skeletal muscle and cardiac tissues are not well described. Although mitochondrial aging is associated with decreased mitochondrial capacity, the genes responsible for the morphological changes in mitochondria during aging are poorly characterized. We measured changes in mitochondrial morphology in aged murine gastrocnemius, soleus, and cardiac tissues using serial block‐face scanning electron microscopy and 3D reconstructions. We also used reverse transcriptase‐quantitative PCR, transmission electron microscopy quantification, Seahorse analysis, and metabolomics and lipidomics to measure changes in mitochondrial morphology and function after loss of mitochondria contact site and cristae organizing system (MICOS) complex genes,Chchd3,Chchd6, andMitofilin. We identified significant changes in mitochondrial size in aged murine gastrocnemius, soleus, and cardiac tissues. We found that both age‐related loss of the MICOS complex and knockouts of MICOS genes in mice altered mitochondrial morphology. Given the critical role of mitochondria in maintaining cellular metabolism, we characterized the metabolomes and lipidomes of young and aged mouse tissues, which showed profound alterations consistent with changes in membrane integrity, supporting our observations of age‐related changes in muscle tissues. We found a relationship between changes in the MICOS complex and aging. Thus, it is important to understand the mechanisms that underlie the tissue‐dependent 3D mitochondrial phenotypic changes that occur in aging and the evolutionary conservation of these mechanisms betweenDrosophilaand mammals.