Characteristics of NAC transcription factors in Solanaceae crops and their roles in responding to abiotic and biotic stresses.

As one of the largest transcription factor (TF) families in plants, the NAC (NAM, ATAF1/2, and CUC2) family plays important roles in response pathways to various abiotic and biotic stresses, such as drought, high salinity, low temperature, and pathogen infection. Although, there are a number of reviews on the involvement of NAC TF in plant responses to biotic and abiotic stresses, most of them are focused on the model plants Arabidopsis thaliana and Oryza sativa, and there is a lack of systematic evaluation of specific species. Solanaceae, the world's third most significant cash crop, has been seriously affected by environmental disturbances in recent years in terms of yield and quality, posing a severe threat to global food security. This review focuses on the functional roles of NAC transcription factors in response to external stresses involved in five important Solanaceae crops: tomato, potato, pepper, eggplant and tobacco, and analyzes the affinities between them. It will provide resources for stress-resistant breeding of Solanaceae crops using transgenic technology.

Colloidal probe dynamics in gelatin solution during the sol-gel transition.

The dynamics of the colloidal probes in a gelatin solution during the time-dependent sol-gel transition was investigated by multi-particle tracking. The relationship between the relaxation of the medium at the critical gel point and the mean square displacement of the probes was elucidated. Based on this understanding, the critical gel point of gelatin and the corresponding critical exponent n were unambiguously determined by the loss angle criterion and the time-cure superposition. The shift factors of the latter are further used to estimate the time/length-scale evolution of the gelatin during the sol-gel transition. The growth of the medium length scale crossed with the two measuring length scales successively at the pre-gel regime. Coinciding with the length-scale crossovers, the probability density function (PDF) of the probe displacements displayed two transient peaks of non-Gaussianity. In the post-gel regime, the third peak of Gaussianity suggested inhomogeneity in the gel network. The non-Gaussianity results from the bifurcation of diffusivity. The present work showed that the non-Gaussian dynamics of the probes are not the direct equivalence of that of the medium, but an effect of length-scale coupling.

Characterization of anthocyanin accumulation, nutritional properties, and postharvest attributes of transgenic purple tomato.

Anthocyanins are natural pigments with diverse physiological roles and protective effects, but most tomatoes produce little. In this study, the anthocyanin characteristics, nutritional properties, and postharvest attributes of purple tomato (SlMYB75-OE) obtained by overexpression of SlMYB75 gene were first analyzed. Compared to wild-type (WT), eight monomeric anthocyanins were newly produced by overexpression of SlMYB75, and further study demonstrated the expression of dihydroflavonol-4-reductase (SlDFR) and two UDP-glycosyltransferase (SlUGTs) genes was activated by SlMYB75. The contents of sugars (sucrose, glucose, and fructose) and citric acid content in SlMYB75-OE were higher and lower, respectively, than in WT. In addition, FRAP and DPPH assays indicated SlMYB75-OE had higher antioxidant capacity, when compared to WT. Moreover, SlMYB75-OE exhibited a longer shelf life and stronger resistance to Botrytis cinerea than WT, and this characteristic was positively correlated with anthocyanin content. These results help to clarify the function of SlMYB75 and provide a reference for tomato breeding.