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Biology subjects

Rogers, C. S.

Publications and source records attributed to Rogers, C. S..

8 recordsLinked to original sources

A non-enzymatic role for METTL3 as an Androgen Receptor co-regulator that promotes prostate cancer proliferation.

Metastatic prostate cancer (PCa) continues to be a major cause of death in males, despite advances in treatment. Most treatment focuses on targeting the Androgen Receptor (AR), the main oncogene responsible for driving most prostate tumors. Despite these therapies targeting AR, the majority of patients still succumb to AR-driven disease. Therefore, there is a critical need for understanding how AR functions to promote prostate cancer growth and identify alternative therapeutic targets in AR-driven PCa. One avenue garnering attention is targeting epigenetic regulators that promote AR-activity; however, the importance of epitranscriptomic regulators, like those that modify mRNAs, is not well understood. Here, we identify a new role for the key catalytic subunit of the RNA N6-methyladenosine (m6A) transferase complex, METTL3, as an AR-coregulator. METTL3 is overexpressed in prostate tumors compared to normal tissue, and METTL3 protein is elevated in AR-expressing cell lines. Depletion of METTL3 significantly reduces proliferation of cancer cells and has no effect on the growth of non-transformed prostate epithelial cells, despite decreasing global m6A levels on mRNA. The catalytic activity of METTL3 is dispensable for the growth of both non-transformed and PCa cell lines, as pharmacologic inhibition of METTL3 does not inhibit proliferation, despite the reduction of global m6A on mRNA. Overexpression of both wild-type and catalytically inactive METTL3 mutants enhances cell viability and rescues cells in which METTL3 is knocked down. Finally, we report on direct interaction between AR and METTL3, their co-localization on chromatin, and reduced AR-cistromic occupancy within cells with METTL3 knockdown. Together, these findings identify a non-enzymatic role for METTL3 in supporting AR-driven transcriptional programs and PCa proliferation.

cancer biology↗

SOX2 utilizes FOXA1 as a heteromeric transcriptional partner to drive proliferation in therapy-resistant prostate cancer

Treatment options and diagnostic outlook for men with advanced, therapy resistant prostate cancer (PCa) are extremely poor; this is primarily due to the common lack of durable response to androgen receptor (AR) targeted therapies and phenotypic transdifferentiation into a particularly lethal subtype known as neuroendocrine prostate cancer (NEPC). In this study, we mechanistically determine that SOX2 (a transcription factor originally repressed by AR) physically binds and acts in a concerted manner with FOXA1 (a key AR pioneering cofactor) to regulate a subset of genes which promote cell cycle progression, and lineage plasticity in AR-refractory prostate cancers. Our findings assert the SOX2/FOXA1 interaction as an important mediator of resistance to AR-targeted therapy and a driver of NEPC and lineage plasticity; their coordinated action and downstream signaling offers a potential novel therapeutic opportunity in late-stage PCa.

cancer biology↗

Real-time feedback reduces participant motion during task-based fMRI

The potential negative impact of head movement during fMRI has long been appreciated. Although a variety of prospective and retrospective approaches have been developed to help mitigate these effects, reducing head movement in the first place remains the most appealing strategy for optimizing data quality. Real-time interventions, in which participants are provided feedback regarding their scan-to-scan motion, have recently shown promise in reducing motion during resting state fMRI. However, whether feedback might similarly reduce motion during task-based fMRI is an open question. In particular, it is unclear whether participants can effectively monitor motion feedback while attending to task-related demands. Here we assessed whether a combination of real-time and between-run feedback could reduce head motion during task-based fMRI. During an auditory word repetition task, 78 adult participants (aged 19-81) were pseudorandomly assigned to receive feedback or not. Feedback was provided FIRMM software that used real-time calculation of realignment parameters to estimate participant motion. We quantified movement using framewise displacement (FD). We found that motion feedback resulted in a statistically significant reduction in participant head motion, with a small-to-moderate effect size (reducing average FD from 0.347 to 0.282). Reductions were most apparent in high-motion events. We conclude that under some circumstances real-time feedback may reduce head motion during task-based fMRI, although its effectiveness may depend on the specific participant population and task demands of a given study.

neuroscience↗

A novel porcine model of CLN3 Batten disease recapitulates clinical phenotypes

Mouse models of CLN3 Batten disease, a rare lysosomal storage disorder with no cure, have improved our understanding of CLN3 biology and therapeutics through their ease of use and a consistent display of cellular pathology. However, the translatability of murine models is limited by disparities in anatomy, body size, life span, and inconsistent, subtle behavior deficits that can be difficult to detect in CLN3 mutant mouse models, limiting their utility in preclinical studies. Here we present a longitudinal characterization of a novel miniswine model of CLN3 disease that recapitulates the most common human pathogenic variant, an exon 7-8 deletion (CLN3{Delta}ex7/8). Progressive pathology and neuron loss is observed in various regions of the CLN3{Delta}ex7/8 miniswine brain and retina. Additionally, mutant miniswine present with vision impairment and motor abnormalities, similar to deficits seen in human patients. Taken together, the CLN3{Delta}ex7/8 miniswine model shows consistent and progressive Batten disease pathology and behavioral impairment mirroring clinical presentation, demonstrating its value in studying the role of CLN3 and safety/efficacy of novel disease modifying therapeutics.

neuroscience↗

Engineering, Generation and Preliminary Characterization of a Humanized Porcine Sickle Cell Disease Animal Model

Mouse models of sickle cell disease (SCD) that faithfully switch from fetal to adult hemoglobin (Hb) have been important research tools that accelerated advancement towards treatments and cures for SCD. Red blood cells (RBCs) in these animals sickled in vivo, occluded small vessels in many organs and resulted in severe anemia like in human patients. SCD mouse models have been valuable in advancing clinical translation of some therapeutics and providing a better understanding of the pathophysiology of SCD. However, mouse models vary greatly from humans in their anatomy and physiology and therefore have limited application for certain translational efforts to transition from the bench to bedside. These differences create the need for a higher order animal model to continue the advancement of efforts in not only understanding relevant underlying pathophysiology, but also the translational aspects necessary for the development of better therapeutics to treat or cure SCD. Here we describe the development of a humanized porcine sickle cell model that like the SCD mice, expresses human [a]-, {beta}- and {gamma}-globin genes under the control of the respective endogenous porcine locus control regions (LCR). We also describe our initial characterization of the SCD pigs and plans to make this model available to the broader research community.

physiology↗

Age-related differences in auditory cortex activity during spoken word recognition

Understanding spoken words requires the rapid matching of a complex acoustic stimulus with stored lexical representations. The degree to which the brain networks supporting spoken word recognition are affected by adult aging remains poorly understood. In the current study we used fMRI to measure the brain responses to spoken words in two conditions: an attentive listening condition, in which no response was required, and a repetition task. Listeners were 29 young adults (aged 19-30 years) and 32 older adults (aged 65-81 years) without self-reported hearing difficulty. We found largely similar patterns of activity during word perception for both young and older adults, centered on bilateral superior temporal gyrus. As expected, the repetition condition resulted in significantly more activity in areas related to motor planning and execution (including premotor cortex and supplemental motor area) compared to the attentive listening condition. Importantly, however, older adults showed significantly less activity in probabilistically-defined auditory cortex than young adults when listening to individual words in both the attentive listening and repetition tasks. Age differences in auditory cortex activity were seen selectively for words (no age differences were present for 1-channel vocoded speech, used as a control condition), and could not be easily explained by accuracy on the task, movement in the scanner, or hearing sensitivity (available on a subset of participants). These findings indicate largely similar patterns of brain activity for young and older adults when listening to words in quiet, but suggest less recruitment of auditory cortex by the older adults.

neuroscience↗

Sex-dependent differences in pain and sleep in a porcine model of Neurofibromatosis type 1

Neurofibromatosis Type 1 (NF1) is an autosomal dominant genetic disorder resulting from germline mutations in the NF1 gene, which encodes neurofibromin. Patients experience a variety of symptoms, but pain in the context of NF1 remains largely underrecognized. Here, we characterize nociceptive signaling and pain behaviors in a miniswine harboring a disruptive NF1 mutation (exon 42 deletion). We explore these phenotypes in relationship to collapsin response mediator protein 2 (CRMP2), a known interactor of neurofibromin. Mechanistically, we found two previously unknown phosphorylated residues of CRMP2 in NF1+/ex42del pig dorsal root ganglia (DRGs) and replicated increased voltage-gated calcium channel currents in NF1+/ex42del pig DRGs previously described in rodent models of NF1. We present the first characterization of pain-related behaviors in a pig model of NF1, identifying unchanged agitation scores, lower tactile thresholds (allodynia), and decreased response latencies to thermal laser stimulation (hyperalgesia) in the NF1 mutant animals; NF1+/ex42del pigs demonstrated sexually dimorphic behaviors. NF1+/ex42del pigs showed reduced sleep quality and increased resting, two health-related quality of life symptoms found to be comorbid in people with NF1 pain. Finally, we show decreased depolarization-evoked calcium influx in both wildtype and NF1+/ex42del pig DRGs treated with CRMP2 phosphorylation inhibitor (5)-lacosamide. Our data supports use of NF1+/ex42del pigs as an ideal model for studying NF1-associated pain and are a better model for understanding the pathophysiology of NF1 compared to rodents. Moreover, our findings demonstrate that interfering with CRMP2 phosphorylation might be a promising therapeutic strategy for NF1-related pain management.

neuroscience↗

Mavacamten stabilizes a folded-back sequestered super-relaxed state of β-cardiac myosin

SummaryMutations in {beta}-cardiac myosin, the predominant motor protein for human heart contraction, can alter power output and cause cardiomyopathy. However, measurements of the intrinsic force, velocity and ATPase activityof myosin have not provided a consistent mechanism to link mutations to muscle pathology. An alternative modelpositsthat mutations in myosin affect the stability ofa sequestered, super-relaxed state (SRX) of the proteinwith very slow ATP hydrolysis and thereby change the number of myosin heads accessible to actin. Here, using a combination of biochemical and structural approaches, we show that purified myosin enters aSRX thatcorresponds to a folded-back conformation, which in muscle fibersresults insequestration of heads around the thick filament backbone. Mutations that cause HCM destabilize this state, while the small molecule mavacamtenpromotes it. These findings provide a biochemical and structural link between the genetics and physiology ofcardiomyopathywith implications for therapeutic strategies.

biochemistry↗