The transcription factor PtoMYB142 enhances drought tolerance in Populus tomentosa by regulating gibberellin catabolism.

Drought stress caused by global warming has resulted in significant tree mortality, driving the evolution of water conservation strategies in trees. Although phytohormones have been implicated in morphological adaptations to water deficits, the molecular mechanisms underlying these processes in woody plants remain unclear. Here, we report that overexpression of PtoMYB142 in Populus tomentosa results in a dwarfism phenotype with reduced leaf cell size, vessel lumen area, and vessel density in the stem xylem, leading to significantly enhanced drought resistance. We found that PtoMYB142 modulates gibberellin catabolism in response to drought stress by binding directly to the promoter of PtoGA2ox4, a GA2-oxidase gene induced under drought stress. Conversely, knockout of PtoMYB142 by the CRISPR/Cas9 system reduced drought resistance. Our results show that the reduced leaf size and vessel area, as well as the increased vessel density, improve leaf relative water content and stem water potential under drought stress. Furthermore, exogenous GA3 application rescued GA-deficient phenotypes in PtoMYB142-overexpressing plants and reversed their drought resistance. By suppressing the expression of PtoGA2ox4, the manifestation of GA-deficient characteristics, as well as the conferred resistance to drought in PtoMYB142-overexpressing poplars, was impeded. Our study provides insights into the molecular mechanisms underlying tree drought resistance, potentially offering novel transgenic strategies to enhance tree resistance to drought.

Using Item Response Theory to Develop a Shortened Version of the Penn State Worry Questionnaire for Children.

The PSWQ-C is a widely used international scale to measure worry traits in children and adolescents. It has been translated into several versions for use in different countries. The purpose of this study was to examine the psychometric characteristics of the Penn State Worry Questionnaire for Children (PSWQ-C) particularly three reverse-scored items, and to develop a shorter version of the PSWQ-C based on Item Response Theory (IRT) methods. 903 children and adolescents of different ages from China participated in the study. This study used the Graded Response Model (GRM) to fit the data and examined the IRT parameters of each item, Item Characteristic Curve, Item Information Functions, and Differential Item Functioning. Eight items with undesirable functioning were removed, while six items with good functioning were retained, resulting in a simplified version of the PSWQ-C. The abbreviated version of the PSWQ-C was subsequently validated for its reliability and validity. The results confirmed that the abbreviated scale is reliable and effective, with a Cronbach's alpha coefficient of 0.84, indicating good reliability. Regarding validity, the abbreviated version of the PSWQ-C demonstrated significant correlations with IUS-12 and MASC, both exceeding 0.60, which closely resembles the correlation of the original PSWQ-C with these two scales. Furthermore, the correlation between the two versions was 0.96, indicating that the abbreviated PSWQ-C can effectively replace the original version and has a broader range of applications.