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Joint Institutions are created from two different universities joining together to create a collaborative research and education effort. Compared to traditional universities, several unique challenges present themselves from this arrangement. We are especially interested in the student experience at UK-China Joint Institutes. We therefore organized a conference with the UK-China Joint Institute Alliance to aggregate knowledge on this issue. This paper summarizes the topics presented and discussed at the conference including: student learning and methods with which to measure and improve it, monitoring and incentivizing student engagement, the transition period from high school to university, teaching evaluations of staff, and lastly, learning and teaching during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

Glucocorticoids (GC) are prescribed for periods > 3 months to 1%–3% of the UK population; 10%–50% of these patients develop hypothalamus‐pituitary–adrenal (HPA) axis suppression, which may last over 6 months and is associated with morbidity and mortality. Recovery of the pituitary and hypothalamus is necessary for recovery of adrenal function. We developed a mouse model of dexamethasone (DEX)‐induced HPA axis dysfunction aiming to further explore recovery in the pituitary. Adult male wild‐type C57BL6/J or Pomc‐eGFP transgenic mice were randomly assigned to receive DEX (approximately 0.4 mg kg–1 bodyweight day–1) or vehicle via drinking water for 4 weeks following which treatment was withdrawn and tissues were harvested after another 0, 1, and 4 weeks. Corticotrophs were isolated from Pomc‐eGFP pituitaries using fluorescence‐activated cell sorting, and RNA extracted for RNA‐sequencing. DEX treatment suppressed corticosterone production, which remained partially suppressed at least 1 week following DEX withdrawal. In the adrenal, Hsd3b2, Cyp11a1, and Mc2r mRNA levels were significantly reduced at time 0, with Mc2r and Cyp11a1 remaining reduced 1 week following DEX withdrawal. The corticotroph transcriptome was modified by DEX treatment, with some differences between groups persisting 4 weeks following withdrawal. No genes supressed by DEX exhibited ongoing attenuation 1 and 4 weeks following withdrawal, whereas only two genes were upregulated and remained so following withdrawal. A pattern of rebound at 1 and 4 weeks was observed in 14 genes that increased following suppression, and in six genes that were reduced by DEX and then increased. Chronic GC treatment may induce persistent changes in the pituitary that may influence future response to GC treatment or stress. [ABSTRACT FROM AUTHOR]

Cellular responses to hypoxia are tissue-specific and dynamic. However, the mechanisms that underlie this differential sensitivity to hypoxia are unknown. Large conductance voltage- and Caactivated K (BK) channels are important mediators of hypoxia responses in many systems. Although BK channels are ubiquitously expressed, alternative pre-mRNA splicing of the single gene encoding their pore-forming [alpha]-subunits provides a powerful mechanism for generating functional diversity. Here, we demonstrate that the hypoxia sensitivity of BK channel [alpha]-subunits is splice-variant-specific. Sensitivity to hypoxia is conferred by a highly conserved motif within an alternatively spliced cysteine-rich insert, the stress-regulated exon (STREX), within the intracellular C terminus of the channel. Hypoxic inhibition of the STREX variant is Ca-sensitive and reversible, and it rapidly follows the change in oxygen tension by means of a mechanism that is independent of redox or CO regulation. Hypoxia sensitivity was abolished by mutation of the serine ($24) residue within the STREX insert. Because STREX splice-variant expression is tissue-specific and dynamically controlled, alternative splicing of BK channels provides a mechanism to control the plasticity of cellular responses to hypoxia. alternative splicing | KCNMA1 oxygen sensing

Large conductance voltage--and calcium-activated potassium ([BK.sub.ca]) channels are important signaling molecules that are regulated by multiple protein kinases and protein phosphatases at multiple sites. The pore-forming [alpha]-subunits, derived from a single gene that undergoes extensive alternative pre-mRNA splicing, assemble as tetramers. Although consensus phosphorylation sites have been identified within the C-terminal domain of [alpha]-subunits, it is not known whether phosphorylation of all or single [alpha]-subunits within the tetramer is required for functional regulation of the channel. Here, we have exploited a strategy to study single-ion channels in which both the [alpha]-subunit splice-variant composition is defined and the number of consensus phosphorylation sites available within each tetramer is known. We have used this approach to demonstrate that cAMP-dependent protein kinase (PKA) phosphorylation of the conserved C-terminal PKA consensus site ($899) in all four [alpha]-subunits is required for channel activation. In contrast, inhibition of [BK.sub.ca] channel activity requires phosphorylation of only a single [alpha]-subunit at a splice insert (STREX)-specific PKA consensus site ([S4.sub.STREX]). Thus, distinct modes of [BK.sub.ca] channel regulation by PKA phosphorylation exist: an 'all-or-nothing' rule for activation and a 'single-subunit' rule for inhibition. This essentially digital regulation has important implications for the combinatorial and conditional regulation of [BK.sub.ca] channels by reversible protein phosphorylation.

Author(s): Rory R. Duncan [1]; Jennifer Greaves [1]; Ulrich K. Wiegand [1]; Ioulia Matskevich [1]; Georg Bodammer [1, 2]; David K. Apps [1]; Michael J. Shipston (corresponding author) [1]; Robert [...]

Coordination of an appropriate stress response is dependent upon anterior pituitary corticotroph excitability in response to hypothalamic secretagogues and glucocorticoid negative feedback. A key determinant of corticotroph excitability is large conductance calcium- and voltage-activated (BK) potassium channels that are critical for promoting corticotrophin-releasing hormone (CRH)-induced bursting that enhances adrenocorticotrophic hormone secretion. Previous studies revealed hypothalamic-pituitary-adrenal axis hyperexcitability following chronic stress (CS) is partly a function of increased corticotroph output. Thus, we hypothesise that chronic stress promotes corticotroph excitability through a BK-dependent mechanism. Corticotrophs from CS mice displayed significant increase in spontaneous bursting, which was suppressed by the BK blocker paxilline. Mathematical modelling reveals that the time constant of BK channel activation, plus properties and proportion of BK channels functionally coupled to L-type Ca2+ channels determines bursting activity. Surprisingly, CS corticotrophs (but not unstressed) display CRH-induced bursting even when the majority of BK channels are inhibited by paxilline, which modelling suggests is a consequence of the stochastic behaviour of a small number of BK channels coupled to L-type Ca2+ channels. Our data reveal that changes in the stochastic behaviour of a small number of BK channels can finely tune corticotroph excitability through stress-induced changes in BK channel properties. Importantly, regulation of BK channel function is highly context dependent allowing dynamic control of corticotroph excitability over a large range of time domains and physiological challenges in health and disease. This is likely to occur in other BK-expressing endocrine cells, with important implications for the physiological processes they regulate and the potential for therapy. [ABSTRACT FROM AUTHOR]

Abstract Background Mice carrying the spontaneous genetic mutation known as Wallerian degeneration slow (Wlds) have a unique neuroprotective phenotype, where axonal and synaptic compartments of neurons are protected from degeneration following a wide variety of physical, toxic and inherited disease-inducing stimuli. This remarkable phenotype has been shown to delay onset and progression in several mouse models of neurodegenerative disease, suggesting that Wlds-mediated neuroprotection may assist in the identification of novel therapeutic targets. As a result, cross-breeding of Wlds mice with mouse models of neurodegenerative diseases is used increasingly to understand the roles of axon and synapse degeneration in disease. However, the phenotype shows strong gene-dose dependence so it is important to distinguish offspring that are homozygous or heterozygous for the mutation. Since the Wlds mutation comprises a triplication of a region already present in the mouse genome, the most stringent way to quantify the number of mutant Wlds alleles is using copy number. Current approaches to genotype Wlds mice are based on either Southern blots or pulsed field gel electrophoresis, neither of which are as rapid or efficient as quantitative PCR (QPCR). Results We have developed a rapid, robust and efficient genotyping method for Wlds using QPCR. This approach differentiates, based on copy number, homozygous and heterozygous Wlds mice from wild-type mice and each other. We show that this approach can be used to genotype mice carrying the spontaneous Wlds mutation as well as animals expressing the Wlds transgene. Conclusion We have developed a QPCR genotyping method that permits rapid and effective genotyping of Wlds copy number. This technique will be of particular benefit in studies where Wlds mice are cross-bred with other mouse models of neurodegenerative disease in order to understand the neuroprotective processes conferred by the Wlds mutation.