7 research outputs found

    Quality Control Autophagy Degrades Soluble ERAD-Resistant Conformers of the Misfolded Membrane Protein GnRHR

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    Molecular chaperones triage misfolded proteins via action as substrate selectors for quality control (QC) machines that fold or degrade clients. Herein, the endoplasmic reticulum (ER) associated Hsp40 JB12 is reported to participate in partitioning mutant conformers of GnRHR, a G-protein coupled receptor, between ER-associated degradation (ERAD) and a novel ERQC-autophagy pathway for membrane proteins. ERQC-autophagy degrades E90K-GnRHR because pools of its partially folded and detergent soluble degradation intermediates are resistant to ERAD. S168R-GnRHR is globally misfolded and disposed of via ERAD, but inhibition of p97, the protein retrotranslocation motor, shunts S168R-GnRHR from ERAD to ERQC autophagy. Partially folded and grossly misfolded forms of GnRHR associate with JB12 and Hsp70. Elevation of JB12 promotes ERAD of S168R-GnRHR, with E90K-GnRHR being resistant. E90K-GnRHR elicits association of the Vps34 autophagy initiation complex with JB12. Interaction between ERassociated Hsp40s and the Vps34 complex permits the selective degradation of ERAD-resistant membrane proteins via ERQC-autophagy

    Models of classroom assessment for course-based research experiences

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    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

    Comparative analysis of antibodies to SARS-CoV-2 between asymptomatic and convalescent patients

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    Summary: The SARS-CoV-2 viral pandemic has induced a global health crisis, which requires more in-depth investigation into immunological responses to develop effective treatments and vaccines. To understand protective immunity against COVID-19, we screened over 60,000 asymptomatic individuals in the Southeastern United States for IgG antibody positivity against the viral Spike protein, and approximately 3% were positive. Of these 3%, individuals with the highest anti-S or anti-RBD IgG level showed a strong correlation with inhibition of ACE2 binding and cross-reactivity against non-SARS-CoV-2 coronavirus S-proteins. We also analyzed samples from 94 SARS-CoV-2 patients and compared them with those of asymptomatic individuals. SARS-CoV-2 symptomatic patients had decreased antibody responses, ACE2 binding inhibition, and antibody cross-reactivity. Our study shows that healthy individuals can mount robust immune responses against SARS-CoV-2 without symptoms. Furthermore, IgG antibody responses against S and RBD may correlate with high inhibition of ACE2 binding in individuals tested for SARS-CoV-2 infection or post vaccination

    Fc-mediated pan-sarbecovirus protection after alphavirus vector vaccination

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    Summary: Group 2B β-coronaviruses (sarbecoviruses) have caused regional and global epidemics in modern history. Here, we evaluate the mechanisms of cross-sarbecovirus protective immunity, currently less clear yet important for pan-sarbecovirus vaccine development, using a panel of alphavirus-vectored vaccines covering bat to human strains. While vaccination does not prevent virus replication, it protects against lethal heterologous disease outcomes in both severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and clade 2 bat sarbecovirus challenge models. The spike vaccines tested primarily elicit a highly S1-specific homologous neutralizing antibody response with no detectable cross-virus neutralization. Rather, non-neutralizing antibody functions, mechanistically linked to FcgR4 and spike S2, mediate cross-protection in wild-type mice. Protection is lost in FcR knockout mice, further supporting a model for non-neutralizing, protective antibodies. These data highlight the importance of FcR-mediated cross-protective immune responses in universal pan-sarbecovirus vaccine designs

    Frontoparietal tDCS Benefits Visual Working Memory in Older Adults With Low Working Memory Capacity

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    Working memory (WM) permits maintenance of information over brief delays and is an essential executive function. Unfortunately, WM is subject to age-related decline. Some evidence supports the use of transcranial direct current stimulation (tDCS) to improve visual WM. A gap in knowledge is an understanding of the mechanism characterizing these tDCS linked effects. To address this gap, we compared the effects of two tDCS montages designed on visual working memory (VWM) performance. The bifrontal montage was designed to stimulate the heightened bilateral frontal activity observed in aging adults. The unilateral frontoparietal montage was designed to stimulate activation patterns observed in young adults. Participants completed three sessions (bilateral frontal, right frontoparietal, sham) of anodal tDCS (20 min, 2 mA). During stimulation, participants performed a visual long-term memory (LTM) control task and a visual WM task. There was no effect of tDCS on the LTM task. Participants receiving right unilateral tDCS showed a WM benefit. This pattern was most robust in older adults with low WM capacity. To address the concern that the key difference between the two tDCS montages could be tDCS over the posterior parietal cortex (PPC), we included new analyses from a previous study applying tDCS targeting the PPC paired with a recognition VWM task. No significant main effects were found. A subsequent experiment in young adults found no significant effect of either tDCS montage on either task. These data indicate that tDCS montage, age and WM capacity should be considered when designing tDCS protocols. We interpret these findings as suggestive that protocols designed to restore more youthful patterns of brain activity are superior to those that compensate for age-related changes
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