The Effects of Autonomy on Emotions and Learning in Game-Based Learning Environments

The current study examined the impact of agency on college students’ emotions and learning during gameplay with CRYSTAL ISLAND, a game-based learning environment designed to foster microbiology learning. 96 undergraduate students (59% female) from a large North American university participated in the study. Participants were randomly assigned to one of three experimental conditions (i.e., full agency, partial agency, no agency), based on the level of control granted during gameplay, and were asked to uncover the source, identity, and best treatment for a mysterious illness. Results revealed participants in the partial agency condition achieved the highest (pre- to post-test) proportional learning gain (PLG), even when controlling for session duration. Additionally, there was a positive correlation between evidence scores of four emotions (anger, fear, confusion, and frustration) and PLG within the partial agency condition—meaning the higher the evidence of the above emotions, the higher the PLG. Further, a stepwise multiple regression showed anger as the sole predictor of PLG. Results from this study have important implications for understanding the role of autonomy and emotions during learning and problem solving with GBLEs designed to foster scientific thinking in STEM. The current study suggests that although GBLEs offer significant learning benefits, they also induce several emotions that can facilitate or inhibit learning gains, requiring further examination

PKC and PKA Phosphorylation Affect the Subcellular Localization of Claudin-1 in Melanoma Cells

<p>Cytoplasmic expression of claudin-1 in metastatic melanoma cells correlates to increased migration, and increased secretion of MMP-2 in a PKC dependent manner, whereas claudin-1 nuclear expression is found in benign nevi. Melanoma cells were transfected with a vector expressing CLDN-1 fused to a nuclear localization signal (NLS). Despite significant nuclear localization of claudin-1, there was still transport of claudin-1 to the cytoplasm. Phorbol ester treatment of cells transfected with NLS-claudin-1 resulted in an exclusion of claudin-1 from the nucleus, despite the NLS. To ascertain whether PKC or PKA were involved in this translocation, we mutated the putative phosphorylation sites within the protein. We found that mutating the PKC phosphorylation sites to mimic a non-phosphorylated state did not cause a shift of claudin-1 to the nucleus of the cells, but mutating the PKA sites did. Mutations of either site to mimic constitutive phosphorylation resulted in cytoplasmic claudin-1 expression. Stable claudin-1 transfectants containing non-phosphorylatable PKA sites exhibited decreased motility. These data imply that subcellular localization of claudin-1 can be controlled by phosphorylation, dicating effects on metastatic capacity.</p

Wnt5A activates the calpain-mediated cleavage of filamin A

We have previously shown that Wnt5A and ROR2, an orphan tyrosine kinase receptor, interact to mediate melanoma cell motility. In other cell types, this can occur through the interaction of ROR2 with the cytoskeletal protein filamin A. Here, we found that filamin A protein levels correlated with Wnt5A levels in melanoma cells. Small interfering RNA (siRNA) knockdown of WNT5A decreased filamin A expression. Knockdown of filamin A also corresponded to a decrease in melanoma cell motility. In metastatic cells, filamin A expression was predominant in the cytoplasm, which western analysis indicated was due to the cleavage of filamin A in these cells. Treatment of nonmetastatic melanoma cells with recombinant Wnt5A increased filamin A cleavage, and this could be prevented by the knockdown of ROR2 expression. Further, BAPTA-AM chelation of intracellular calcium also inhibited filamin A cleavage, leading to the hypothesis that Wnt5A/ROR2 signaling could cleave filamin A through activation of calcium-activated proteases, such as calpains. Indeed, WNT5A knockdown decreased calpain 1 expression, and by inhibiting calpain 1 either pharmacologically or using siRNA, it decreased cell motility. Our results indicate that Wnt5A activates calpain-1, leading to the cleavage of filamin A, which results in a remodeling of the cytoskeleton and an increase in melanoma cell motility

Activation of Wnt5A signaling is required for CXC chemokine ligand 12–mediated T-cell migration

Chemokines mediate the signaling and migration of T cells, but little is known about the transcriptional events involved therein. Microarray analysis of CXC chemokine ligand (CXCL) 12−treated T cells revealed that Wnt ligands are significantly up-regulated during CXCL12 treatment. Real-time polymerase chain reaction and Western blot analysis confirmed that the expression of noncanonical Wnt pathway members (eg, Wnt5A) was specifically up-regulated during CXCL12 stimulation, whereas β-catenin and canonical Wnt family members were selectively down-regulated. Wnt5A augmented signaling through the CXCL12-CXCR4 axis via the activation of protein kinase C. Moreover, Wnt5A expression was required for CXCL12–mediated T-cell migration, and rWnt5A sensitized human T cells to CXCL12-induced migration. Furthermore, Wnt5A expression was also required for the sustained expression of CXCR4. These results were further supported in vivo using EL4 thymoma metastasis as a model of T-cell migration. Together, these data demonstrate that Wnt5A is a critical mediator of CXCL12-CXCR4 signaling and migration in human and murine T cells

Regulation of CCR5 expression and MIP-1α production in CD4(+) T cells from patients with rheumatoid arthritis

Production of CCR5 expression and MIP-1α, a ligand of CCR5, by CD4(+) T cells from patients with rheumatoid arthritis (RA) were studied. We analysed further the influence of IL-15 stimulation, CD40/CD40 ligand (CD40L) interaction and CCR5 promotor polymorphism. One hundred and fifty-five RA patients and another 155 age- and sex-matched healthy individuals were enrolled. Peripheral CD4(+) and double negative (DN) T cells from patients had lower portions of CCR5, whereas synovial CD4(+) and DN T cells showed a much higher CCR5 expression. IL-15 significantly up-regulated the expression of CCR5 on purified CD4(+) T cells. CD40L expression on synovial CD4(+) T cells was increased greatly in CCR5(+) portions by IL-15. MIP-1α production by synovial CD4(+) T cells was also enhanced by IL-15. Co-culture of CD40 expressing synovial fibroblasts with IL-15-activated synovial CD4(+) T cells significantly increased MIP-1α production. Expression of CCR5 on patients’ CD4(+) T cells was not influenced by the promotor polymorphism of CCR5 gene. Taken together, these data suggest CCR5(+)CD4(+) T cells infiltrate the inflamed synovium and IL-15 up-regulates CCR5 and CD40L expression further and enhance MIP-1α production in synovial CD4(+) T cells. Production of MIP-1α by synovial fibroblasts is significantly increased by engagement of CD40 with CD40L. Synovial microenvironment plays a potential role in regulation of CCR5(+)CD4(+) T cells in rheumatoid joints