UMBC Biological Sciences Department

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With more than 30 tenured and tenure-track faculty members and lecturers, UMBC’s Department of Biological Sciences is one of the university’s largest academic departments encompassing a wide breadth of research and teaching. Research faculty in the Biological Sciences focus on:
  • Cell Biology
  • Computational Biology
  • Developmental Biology & Immunology
  • Evolutionary Biology
  • Molecular Biology & Genetics
  • Neuroscience
  • Plant Biology
The department offers a full complement of baccalaureate and graduate programs leading to B.A., B.S., M.S., and Ph.D. degrees, which are recognized for their emphasis on research, scientific approach, faculty contact, and extensive laboratory offerings. These programs serve to train a broad spectrum of future biologists and researchers, and to prepare students for graduate and professional schools.

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Recent Submissions

Now showing 1 - 20 of 682
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    Steroid hormone signaling synchronizes cell migration machinery, adhesion, and polarity to direct collective movement
    (The Company of Biologists, 2024-02-07) Bhattacharya, Mallika; Starz-Gaiano, Michelle
    Migratory cells – either individually or in cohesive groups – are critical for spatiotemporally-regulated processes such as embryonic development and wound healing. Their dysregulation is the underlying cause of formidable health problems such as birth defects and metastatic cancers. Border cell behavior during Drosophila oogenesis provides an effective model to study temporally-regulated, collective cell migration in vivo. Developmental timing in flies is primarily controlled by the steroid hormone ecdysone, which acts through a well-conserved, nuclear hormone receptor complex. Ecdysone signaling determines the timing of border cell migration but the molecular mechanisms governing this remain obscure. We found that border cell clusters expressing a dominant negative form of ecdysone receptor extend ineffective protrusions. Additionally, these clusters have aberrant spatial distributions of E-cadherin, apical domain markers and activated myosin that do not overlap. Remediating their expression or activity individually in ecdysone signaling-mutant clusters did not restore proper migration. We propose that ecdysone signaling synchronizes the functional distribution of E-cadherin, atypical protein kinase C, Discs large, and activated myosin post-transcriptionally to coordinate adhesion, polarity, and contractility and temporally control collective cell migration.
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    An evolutionarily conserved phosphoserine-arginine salt bridge in the interface between ribosomal proteins uS4 and uS5 regulates translational accuracy in Saccharomyces cerevisiae
    (Oxford University Press, 2024-02-10) Joshi, Kartikeya; Luisi, Brooke; Wunderlin, Grant; Saleh, Sima; Lilly, Anna; Okusolubo, Temiloluwa; Farabaugh, Philip
    Protein-protein and protein–rRNA interactions at the interface between ribosomal proteins uS4 and uS5 are thought to maintain the accuracy of protein synthesis by increasing selection of cognate aminoacyl-tRNAs. Selection involves a major conformational change—domain closure—that stabilizes aminoacyl-tRNA in the ribosomal acceptor (A) site. This has been thought a constitutive function of the ribosome ensuring consistent accuracy. Recently, the Saccharomyces cerevisiae Ctk1 cyclin-dependent kinase was demonstrated to ensure translational accuracy and Ser238 of uS5 proposed as its target. Surprisingly, Ser238 is outside the uS4-uS5 interface and no obvious mechanism has been proposed to explain its role. We show that the true target of Ctk1 regulation is another uS5 residue, Ser176, which lies in the interface opposite to Arg57 of uS4. Based on site specific mutagenesis, we propose that phospho-Ser176 forms a salt bridge with Arg57, which should increase selectivity by strengthening the interface. Genetic data show that Ctk1 regulates accuracy indirectly; the data suggest that the kinase Ypk2 directly phosphorylates Ser176. A second kinase pathway involving TORC1 and Pkc1 can inhibit this effect. The level of accuracy appears to depend on competitive action of these two pathways to regulate the level of Ser176 phosphorylation.
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    Sex-specific mechanisms underlie long-term potentiation at hippocampus-nucleus 2 accumbens synapses
    (2024-01-24) Copenhaver, Ashley E.; LeGates, Tara
    Sex differences have complicated our understanding of the neurobiological basis of many behaviors that are key for survival. As such, continued elucidation of the similarities and differences between sexes is necessary in order to gain insight into brain function and vulnerability. The connection between the hippocampus (Hipp) and nucleus accumbens (NAc) is a crucial site where modulation of neuronal activity mediates reward-related behavior. Our previous work demonstrated that long-term potentiation (LTP) of Hipp-NAc synapses is rewarding, and that mice can make learned associations between LTP of these synapses and the contextual environment in which LTP occurred. Here, we investigate sex differences in the mechanisms underlying Hipp-NAc LTP using whole-cell electrophysiology and pharmacology. We found that males and females display similar magnitudes of Hipp-NAc LTP which occurs postsynaptically. However, LTP in females requires L-type voltage-gated Ca²⁺ channels (VGCC) for postsynaptic Ca²⁺ influx, while males rely on NMDA receptors (NMDAR). Additionally, females require estrogen receptor α (ERα) activity for LTP while males do not. These differential mechanisms converge as LTP in both sexes depends on CAMKII activity and occurs independently of dopamine-1 receptor (D1R) activation. Our results have elucidated sex-specific molecular mechanisms for LTP in an integral excitatory pathway that mediates reward-related behaviors, emphasizing the importance of considering sex as a variable in mechanistic studies. Continued characterization of sex-specific mechanisms underlying plasticity will offer novel insight into the neurophysiological basis of behavior, with significant implications for understanding how diverse processes mediate behavior and contribute to vulnerability to developing psychiatric disorders.
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    Guidelines for minimal reporting requirements, design and interpretation of experiments involving the use of eukaryotic dual gene expression reporters (MINDR)
    (2024-01-15) Loughran, Gary; Andreev, Dmitry E.; Terenin, Ilya M.; Namy, Olivier; Farabaugh, Philip; et al
    Dual reporters, which encode two distinct proteins within the same mRNA, have played a crucial role in identifying and characterizing new instances of unconventional eukaryotic translation mechanisms. These mechanisms include initiation by internal ribosomal entry sites (IRESs), ribosomal frameshifting, stop codon readthrough, and reinitiation. This design allows one reporter's expression to be influenced by the specific mechanism under investigation, while the other reporter serves as an internal control. However, challenges arise when intervening sequences are placed between these two reporters. Such sequences can inadvertently impact the expression or function of either reporter, independently of translation-related changes. These effects may occur because of cryptic elements inducing or affecting transcription initiation, splicing, polyadenylation, and antisense transcription, as well as unexpected effects of the translated test sequences on the stability and activity of the reporters. Unfortunately, these unintended effects may lead to incorrect conclusions being published in the scientific literature. To address this issue and assist the scientific community in accurately interpreting dual reporter experiments, we have developed comprehensive guidelines. These guidelines cover experiment design, interpretation, and the minimal requirements for reporting results. They are designed to aid researchers conducting these experiments, as well as reviewers, editors, and other investigators who seek to evaluate published data.
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    Draft genome from facultatively parthenogenetic Opiliones indicates frequent mitonuclear sequence transfer and novel full-length insertions
    (2024-01-11) Stellwagen, Sarah; Burns, Mercedes
    Background: Facultative parthenogenesis and intra-population mixed ploidy are rare in animals. These unique characteristics allow opportunities to investigate the relationship between sexual modality and ploidy. We have completed a draft genome of the Japanese harvester ("daddy-longlegs") Leiobunum manubriatum, a species which reproduces sexually and asexually, and with mixed diploid and tetraploid populations in some areas. Results: We combined Oxford Nanopore’s MinION long-read sequencing platform with Dovetail Hi-C scaffolding to assemble the haploid genome for the diploid race, which is approximately 336 MBp after collapsing heterozygous sequence. The assembly’s completeness was measured using BUSCOs from Eukaryota (complete: 92.6%), Arthropoda (complete: 96.9%), and Arachnida (complete: 95.3%). We searched raw sequence reads and the draft genome for nuclear mitochondrial DNA (numt) sequences. While only one complete mitochondrial genomic transfer was found in the draft genome, there are at least 12 complete numts across 9 reads within the raw sequencing data that were lost during the assembly process. Conclusions: The genome of the L. manubriatum diploid race is an invaluable resource not only for opilionid research, but also for facilitating studies investigating the evolution of their unique reproductive mode and mixed ploidy. To our knowledge, this is the first published genome of a wild-derived facultative parthenogen. Future work will leverage this resource in comparative genomics and transcriptomics of L. manubriatum to understand the connection between ploidy and sexual strategy.
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    Current models in bacterial hemicellulase-encoding gene regulation
    (Springer, 2024-01-04) Novak, Jessica K.; Gardner, Jeffrey
    The discovery and characterization of bacterial carbohydrate-active enzymes is a fundamental component of biotechnology innovation, particularly for renewable fuels and chemicals; however, these studies have increasingly transitioned to exploring the complex regulation required for recalcitrant polysaccharide utilization. This pivot is largely due to the current need to engineer and optimize enzymes for maximal degradation in industrial or biomedical applications. Given the structural simplicity of a single cellulose polymer, and the relatively few enzyme classes required for complete bioconversion, the regulation of cellulases in bacteria has been thoroughly discussed in the literature. However, the diversity of hemicelluloses found in plant biomass and the multitude of carbohydrate-active enzymes required for their deconstruction has resulted in a less comprehensive understanding of bacterial hemicellulase-encoding gene regulation. Here we review the mechanisms of this process and common themes found in the transcriptomic response during plant biomass utilization. By comparing regulatory systems from both Gram-negative and Gram-positive bacteria, as well as drawing parallels to cellulase regulation, our goals are to highlight the shared and distinct features of bacterial hemicellulase-encoding gene regulation and provide a set of guiding questions to improve our understanding of bacterial lignocellulose utilization.
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    Patient-reported barriers to prenatal diagnosis of congenital heart defects: A mixed-methods study
    (Wiley, 2023-12-18) Woo, Joyce L.; Burton, Shelvonne; Iyengar, Tara; Sivakumar, Adithya; Spiewak, Sarah; Wakulski, Renee; Grobman, William A.; Davis, Matthew M.; Yee, Lynn M.; Patel, Angira; Johnson, Joyce T.; Patel, Sheetal; Gandhi, Rupali
    Objective To ascertain patient-reported, modifiable barriers to prenatal diagnosis of congenital heart defects (CHDs). Methods This was a mixed-methods study among caretakers of infants who received congenital heart surgery from 2019 to 2020 in the Chicagoland area. Quantitative variables measuring sociodemographic characteristics and prenatal care utilization, and qualitative data pertaining to patient-reported barriers to prenatal diagnosis were collected from electronic health records and semi-structured phone surveys. Thematic analysis was performed using a convergent parallel approach. Results In total, 160 caretakers completed the survey, 438 were eligible for survey, and 49 (31%) received prenatal care during the COVID-19 pandemic. When comparing respondents and non-respondents, there was a lower prevalence of maternal Hispanic ethnicity and a higher prevalence of non-English/Spanish-speaking households. Of all respondents, 34% reported an undetected CHD on ultrasound or echocardiogram, while 79% reported at least one barrier to prenatal diagnosis related to social determinants of health. Among those social barriers, the most common were difficulty with appointment scheduling (n = 12, 9.5%), far distance to care/lack of access to transportation (n = 12, 9.5%) and difficulty getting time off work to attend appointments (n = 6, 4.8%). The latter two barriers were correlated. Conclusion While technical improvements in the detection of CHDs remain an important area of research, it is equally critical to produce evidence for interventions that mitigate barriers to prenatal diagnosis due to social determinants of health.
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    Functional Analysis of BrutonÕs Tyrosine Kinase: A Bottom-up Proteomics Approach
    (2021-01-01) Liu, Shuaishuai; Bieberich, Charles J; Biological Sciences; Biological Sciences
    BrutonÕs tyrosine kinase (BTK) is a non-receptor tyrosine protein kinase indispensable in B lymphocyte development. After being activated by the B cell receptor (BCR), BTK subsequently signals downstream to promote B cell survival and development. In humans, loss of BTK function results in X-linked agammaglobulinemia (XLA), an immunodeficiency characterized by a defect in B cell development that leads to a dearth of circulating B cells. In line with its role in normal B cells, BTK is also essential for malignant B cell survival . Hence, BTK has become an attractive target for treatment of B cell malignancies. Targeting BTK with small molecular inhibitors has achieved impressive clinical outcomes in chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) cases. However, primary and acquired resistance to BTK inhibitors is common and often leads to clinical failure. To address these challenges, a comprehensive understanding of BTK function would be highly informative. In this project, we developed a novel bottom-up proteomic approach, termed the Native In-gel Kinase-Substrate Assay (NIKSA), to analyze BTK function by globally identifying its physiological substrates. A BTK NIKSA performed on a K562 cell extract found 926 proteins as potential direct BTK substrates that could be ordered into distinct cellular pathways by pathway analysis. The top pathway found as a target of BTK control was the ubiquitin-proteasome pathway. In subsequent analyses, we found multiple proteasome subunits that are robust in vitro BTK substrates and can physically interact with BTK in vivo. Furthermore, we demonstrated that modulating BTK activity in vivo led to concomitant changes in proteasome activity. To exploit this finding in a therapeutically meaningful manner, we demonstrated that combining BTK activation with proteasome inhibition effectively killed malignant B cells in cell culture and diminished B cell tumor growth in a xenograft setting in mice. In addition, we demonstrated that BTK phosphorylates the oncogenic kinase ABL and increases its catalytic activity, providing a rationale for combining BTK and ABL inhibitors to treat chronic lymphocytic leukemia (CLL). Taken together, these data demonstrate that proteomic profiling of kinase substrates is an effective strategy to illuminate pathways under kinase control. Furthermore, we demonstrate how this new knowledge can be exploited to develop new rational combinatorial therapies to treat hematological malignancies to reduce the morbidity and mortality of these devastating diseases. Application of this general methodology to other oncogenic kinases holds great promise to inform therapeutic approaches to treat other malignancies.
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    The Mechanistic Regulation of Pattern and Shape: A Systems Biology Approach
    (2023-01-01) Ko, Jason Michael; Lobo, Daniel; Biological Sciences; Biological Sciences
    During the development of a multicellular organism, cells must adopt both the proper fates and the correct spatial locations to form the various tissues and organs required for embryogenesis. However, understanding the dynamic mechanochemical feedback between patterning signals and morphological shape remains an open challenge. This dissertation developed mathematical models and machine learning techniques to investigate the interplay between pattern and shape in a variety of multicellular organisms. First, we developed and studied a continuous mathematical model of regulated differential cell-cell adhesion that can explain how changes in adhesion at the cellular level produce broad changes at the tissue level. This model can demonstrate the mechanisms responsible for classical cell sorting behaviors, cell intercalation in proliferating populations, and the involution of germ layer cells induced by a diffusing morphogen during gastrulation. We then employed this modeling approach to explain the regulation of whole-body shape in the planarian flatworms via the feedback interaction between morphogen signals and tissue shapes during growth and degrowth. For this, we developed a machine learning pipeline to train this model of pattern and shape using standardized experimental data of planarian shape over time. We demonstrated that the trained model can recapitulate the precise dynamics of planarian whole-body proportions during growth. Furthermore, by varying only two constants controlling the signaling at the poles and the overall rate of cell apoptosis, the model dynamics can transition from growth to degrowth. Finally, we applied this model of regulated pattern and shape to understanding planarian regeneration. Using the same parameter scan technique that produced the correct parameters for degrowth simulation, we were able to find a parameter set that exhibits the general shape dynamics seen during the reshaping phase of planarian regeneration. Overall, we were able to produce the first dynamic mathematical model that includes the mechanochemical feedback between pattern and shape in planarians. This mathematical and computational approach can enable further advancements in understanding complex phenomena in biology where pattern and shape are intertwined, spanning the fields of regenerative, developmental, and cancer biology.
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    MOLECULAR ADAPTATIONS TO FLUCTUATIONS IN OXYGEN LEVELS
    (2023-01-01) Hufford, Timothy Michael; Brewster, Rachel M; Biological Sciences; Biological Sciences
    Oxygen is essential for cell metabolism, hence oxygen deprivation can be severely detrimental. A diverse array of organisms can adapt to changes in oxygen levels, and conserved adaptive responses represent therapeutic targets. The organisms that tolerate the widest range of oxygen levels adapt to these changes by suppressing energy-demanding activities until oxygen is restored, a response known as metabolic suppression. One such organism is the zebrafish, which adapts to low oxygen conditions (hypoxia) or no oxygen (anoxia). Many organisms capable of surviving the oxygen deprivation do so by suppressing energy-demanding cellular activities and only using those that promote survival. Here, we have asked to what degree transcriptional changes mediate adaptation to anoxia. Previous studies from the Brewster laboratory identified Ndrg1a as a protein that mediates metabolic suppression under anoxia. We observe that ndrg1a transcript is increased following exposure to anoxia, with expression observed in tissues sensitive to hypoxic damage such as the kidney and inner ear. We next more broadly asked what other genes are transcribed under anoxia by performing a transcriptome-wide analysis. To our surprise, we found that anoxia elicits differential expression of over 2800 genes, nearly 1200 of which are upregulated. While some of these genes may mediate metabolic suppression, the majority appear to be required for adaptation following the return to normal oxygen conditions. These findings suggest that anoxia triggers an active transcriptional response, that may represent an energetic investment for surviving reoxygenation that can be more damaging to cells than hypoxia itself. One of the most significantly increased genes, gadd45ba, was chosen for further study. Analysis of Gadd45b expression revealed that it is expressed in erythrocyte (red blood cell) precursors in the hematopoietic stem cell niche. In response to anoxia, its expression levels increased and Gadd45b-positive cells were now mobilized into circulation. To address the functional relevance of these observations, gadd45ba was depleted using a morpholino that disrupts splicing. Embryos injected with the morpholino were defective in red blood cell differentiation, with fewer and larger cells that failed to enter circulation following exposure to anoxia. Erythropoiesis, or red blood cell production, is an essential process for supplying our tissues with sufficient oxygen under normal conditions, and this process must be further increased to cope with hypoxic conditions. Our work identifies gadd45ba as a novel gene implicated in hypoxia-induced erythropoiesis.
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    EXPLORING MELANOPSIN FUNCTION IN MAMMALS WITH DIVERSE PHOTORECEPTOR ARCHITECTURE
    (2023-01-01) Algrain, Haya; Robinson, Phyllis R; Biological Sciences; Biological Sciences
    The properties of visual pigments and retinal architecture in mammals are adapted to suit diverse light environments. Intrinsically photosensitive retinal ganglion cells (ipRGCs), which express the visual pigment melanopsin, integrate both their intrinsic photoresponse and input from rods and cones to mediate both image and non-image forming visual functions. Molecular modeling and genetic analyses suggest that the absorption spectra of all mammalian melanopsins are nearly identical. However, melanopsin expression varies significantly among mammals with different photoreceptor architectures, suggesting potential variability in melanopsin signaling kinetics and melanopsin-mediated behavior. This study investigates the impact of the evolutionary gain or loss of cone photoreceptor types on melanopsin signaling kinetics. This study also investigates the expression of melanopsin the nine-banded armadillo, a terrestrial monochromat. Detailed analysis of phosphorylation at the C-terminus of mouse melanopsin has identified key residues that are important for the kinetics of ipRGC-regulated behavior. Using an in vitro fluorescent calcium signaling assay, our results demonstrate a correlation between delayed melanopsin activation and deactivation kinetics in rod monochromats. Furthermore, mammals with activity patterns during the day (trichromats and dichromats) have similar or faster melanopsin signaling kinetics than wildtype mouse melanopsin. In addition, we confirmed the expression of melanopsin in the nine-banded armadillo. These findings suggest that the presence or absence of photopic vision (i.e., the possession of cone opsins) is a key evolutionary factor driving rapid melanopsin signaling in ipRGCs.?
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    Sparsity in an artificial neural network predicts beauty: Towards a model of processing-based aesthetics
    (PLOS, 2023-12-04) Dibot, Nicolas M.; Tieo, Sonia; Mendelson, Tamra; Puech, William; Renoult , Julien P.
    Generations of scientists have pursued the goal of defining beauty. While early scientists initially focused on objective criteria of beauty (‘feature-based aesthetics’), philosophers and artists alike have since proposed that beauty arises from the interaction between the object and the individual who perceives it. The aesthetic theory of fluency formalizes this idea of interaction by proposing that beauty is determined by the efficiency of information processing in the perceiver’s brain (‘processing-based aesthetics’), and that efficient processing induces a positive aesthetic experience. The theory is supported by numerous psychological results, however, to date there is no quantitative predictive model to test it on a large scale. In this work, we propose to leverage the capacity of deep convolutional neural networks (DCNN) to model the processing of information in the brain by studying the link between beauty and neuronal sparsity, a measure of information processing efficiency. Whether analyzing pictures of faces, figurative or abstract art paintings, neuronal sparsity explains up to 28% of variance in beauty scores, and up to 47% when combined with a feature-based metric. However, we also found that sparsity is either positively or negatively correlated with beauty across the multiple layers of the DCNN. Our quantitative model stresses the importance of considering how information is processed, in addition to the content of that information, when predicting beauty, but also suggests an unexpectedly complex relationship between fluency and beauty.
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    Models of classroom assessment for course-based research experiences
    (Frontiers, 2023-11-28) David I. Hanauer; Tong Zhang; Mark J. Graham; Sandra D. Adams; Steven Caruso; et al
    Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment—(1) Assessing Laboratory Work and Scientific Thinking; (2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; (3) Appraising Forms of Scientific Communication; and (4) Metacognition of Learning—along with a set of practices for each aim. These aims and practices of assessment were then integrated with previously developed models of course-based research instruction to reveal an assessment program in which instructors provide extensive feedback to support productive student engagement in research while grading those aspects of research that are necessary for the student to succeed. Assessment conducted in this way delicately balances the need to facilitate students’ ongoing research with the requirement of a final grade without undercutting the important aims of a CRE education.
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    Candidate Autism Gene NRX1 Leads to Ectopic Synapses in Nociceptive Neurons in Drosophila Larvae
    (IBRO Neuroscience Report, 2023-10) Gualtieri, Claudia; Vonhoff, Fernando J.
    Synaptic pruning is a neuroplastic process leading to the withdrawal of ectopic synapses formed during the initial phases of neuronal development. Extensive research has shown evidence of synaptic pruning occurring in both the central nervous system (CNS) and peripheral nervous system (PNS). However, the molecular mechanisms underlying synaptic pruning remain incompletely understood. The process of synapse pruning is crucial during development in multiple organisms as it has also been linked to the onset of neurodevelopmental disorders like autism. We determined the anatomical effects of candidate autism genes in vivo using the Drosophila model. Starting from the hypothesis that candidate autism genes would lead to the presence of ectopic synapses that branch off stereotypic connectivity patterns, we assessed the stereotypic synaptic innervations of cIV nociceptive sensory neurons development. The candidate autism genes of the transsynaptic adhesion proteins neurexin-1 and neuroligin-3 were downregulated using RNAi constructs. Anatomical defects were assessed by counting the number of ectopic neurites. Data shows increased number of ectopic neurites in the stereotypic ladder structure formed in the CNS by the axonal projection of nociceptive neurons when the candidate autism gene neurexin-1 is downregulated. Additionally, we are in the process of assessing the synaptic connectivity between cIV sensory neurons and the postsynaptic basin interneurons during embryonic and larval development using the GFP Reconstitution Across Synaptic Partners (GRASP) technique. This data will reveal the synaptic partnership between nociceptors and basin interneurons -1 and -4 at different stages of Drosophila development. Also, it will provide the groundwork for determining the potential role of synaptic pruning on the synaptic connectivity of nociceptors to basins, offering the setting for future pruning disruption investigations. Our findings will offer the basis for investigating the processes leading to the failure in the elimination of ectopic synapses providing insights into the molecular mechanisms regulating synaptic refinement.
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    The SMYD3-MAP3K2 signaling axis promotes tumor aggressiveness and metastasis in prostate cancer
    (AAAS, 2023-11-17) Ikram, Sabeen; Rege, Apurv; Negesse, Maraki; Casanova, Alexandre G.; Reynoird, Nicolas; Green, Erin
    Aberrant activation of Ras/Raf/mitogen-activated protein kinase (MAPK) signaling is frequently linked to metastatic prostate cancer (PCa); therefore, the characterization of modulators of this pathway is critical for defining therapeutic vulnerabilities for metastatic PCa. The lysine methyltransferase SET and MYND domain 3 (SMYD3) methylates MAPK kinase kinase 2 (MAP3K2) in some cancers, causing enhanced activation of MAPK signaling. In PCa, SMYD3 is frequently overexpressed and associated with disease severity; however, its molecular function in promoting tumorigenesis has not been defined. We demonstrate that SMYD3 critically regulates tumor-associated phenotypes via its methyltransferase activity in PCa cells and mouse xenograft models. SMYD3-dependent methylation of MAP3K2 promotes epithelial-mesenchymal transition associated behaviors by altering the abundance of the intermediate filament vimentin. Furthermore, activation of the SMYD3-MAP3K2 signaling axis supports a positive feedback loop continually promoting high levels of SMYD3. Our data provide insight into signaling pathways involved in metastatic PCa and enhance understanding of mechanistic functions for SMYD3 to reveal potential therapeutic opportunities for PCa.
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    From natural to sexual selection: Revealing a hidden preference for camouflage patterns
    (2023-09-29) Héjja-Brichard, Yseult; Raymond, Michel; Cuthill, Innes C.; Mendelson, Tamra; Renoult, Julien P.
    Natural and sexual selection can be in conflict in driving the evolution of sexual ornamentation. Sexual selection favours detectability to potential mates, whereas natural selection penalises detectability to avoid predators. Focusing on signal efficiency rather than detectability, however, suggests that natural and sexual selection need not be antagonistic. Considerable evidence demonstrates that people prefer images that match the statistics of natural scenes, likely because they are efficiently processed by the brain. This “processing bias” suggests that background-matching camouflage can be favoured by natural and sexual selection. We conducted an online experiment and showed for the first time human preference for camouflaged stimuli. Because the underlying visual mechanisms are shared across vertebrates, our results suggest that camouflage patterns could serve as evolutionary precursors of sexual signals.
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    The Stomata Lab. What the past can tell us about our future - using fossil and modern plants to model atmospheric carbon dioxide
    (QUBES, 2023-11-02) Wesley, Gina; Livernoche, Kelly; McNamara, Sean; Gretes, William; Bell, Allison; Newtoff, Kiersten; Leips, Jeff; Barclay, Richard; Killen, Heather
    Students will develop a mathematical model of the relationship between atmospheric CO2 and the number of stomata on a leaf (Stomata Index). They will evaluate the model graphically, statistically, and biologically, and then use it to estimate CO2 levels in the distant past.