Creative and Stylistic Devices Employed by Children During a Storybook Narrative Task: A Cross-Cultural Study

Purpose: The purpose of this study was to analyze the effects of culture on the creative and stylistic features children employ when producing narratives based on wordless picture books. Method: Participants included 60 first- and second-grade African American, Latino American, and Caucasian children. A subset of narratives based on wordless picture books collected as part of a larger study was coded and analyzed for the following creative and stylistic conventions: organizational style (topic centered, linear, cyclical), dialogue (direct, indirect), reference to character relationships (nature, naming, conduct), embellishment (fantasy, suspense, conflict), and paralinguistic devices (expressive sounds, exclamatory utterances). Results: Many similarities and differences between ethnic groups were found. No significant differences were found between ethnic groups in organizational style or use of paralinguistic devices. African American children included more fantasy in their stories, Latino children named their characters more often, and Caucasian children made more references to the nature of character relationships. Conclusion: Even within the context of a highly structured narrative task based on wordless picture books, culture influences children’s production of narratives. Enhanced understanding of narrative structure, creativity, and style is necessary to provide ecologically valid narrative assessment and intervention for children from diverse cultural backgrounds

Conformational dynamics are a key factor in signaling mediated by the receiver domain of a sensor histidine kinase from Arabidopsis thaliana

Multistep phosphorelay MSP cascades mediate responses to a wide spectrum of stimuli, including plant hormonal signaling, but several aspects of MSP await elucidation. Here, we provide first insight into the key step of MSP mediated phosphotransfer in a eukaryotic system, the phosphorylation of the receiver domain of the histidine kinase CYTOKININ INDEPENDENT 1 CKI1RD from Arabidopsis thaliana. We observed that the crystal structures of free, Mg2 bound, and beryllofluoridated CKI1RD a stable analogue of the labile phosphorylated form were identical and similar to the active state of receiver domains of bacterial response regulators. However, the three CKI1RD variants exhibited different conformational dynamics in solution. NMR studies revealed that Mg2 binding and beryllofluoridation alter the conformational equilibrium of the amp; 946;3 amp; 945;3 loop close to the phosphorylation site. Mutations that perturbed the conformational behavior of the amp; 946;3 amp; 945;3 loop while keeping the active site aspartate intact resulted in suppression of CKI1 function. Mechanistically, homology modeling indicated that the amp; 946;3 amp; 945;3 loop directly interacts with the ATP binding site of the CKI1 histidine kinase domain. The functional relevance of the conformational dynamics observed in the amp; 946;3 amp; 945;3 loop of CKI1RD was supported by a comparison with another A. thaliana histidine kinase, ETR1. In contrast to the highly dynamic amp; 946;3 amp; 945;3 loop of CKI1RD, the corresponding loop of the ETR1 receiver domain ETR1RD exhibited little conformational exchange and adopted a different orientation in crystals. Biochemical data indicated that ETR1RD is involved in phosphorylation independent signaling, implying a direct link between conformational behavior and the ability of eukaryotic receiver domains to participate in MS