Multiomic Analysis Reveals Core Regulatory Mechanisms underlying Steroidal Glycoalkaloid Metabolism in Potato Tubers.

Steroidal glycoalkaloids (SGAs) present in germinated potato tubers are toxic; however, the mechanisms underlying SGA metabolism are poorly understood. Therefore, integrated transcriptome, metabolome, and hormone analyses were performed in this study to identify and characterize the key regulatory genes, metabolites, and phytohormones related to glycoalkaloid regulation. Based on transcriptome sequencing of bud eyes of germinated and dormant potato tubers, a total of 6260 differentially expressed genes were identified, which were mainly responsible for phytohormone signal transduction, carbohydrate metabolism, and secondary metabolite biosynthesis. Two TCP14 genes were identified as the core transcription factors that potentially regulate SGA synthesis. Metabolite analysis indicated that 149 significantly different metabolites were detected, and they were enriched in metabolic and biosynthetic pathways of secondary metabolites. In these pathways, the α-solanine content was increased and the expression of genes related to glycoalkaloid biosynthesis was upregulated. Levels of gibberellin and jasmonic acid were increased, whereas that of abscisic acid was decreased. This study lays a foundation for investigating the biosynthesis and regulation of SGAs and provides the reference for the production and consumption of potato tubers.

Formation and instability of silver nanofilament in Ag-based programmable metallization cells.

In this paper, we report on the formation and rupture of Ag nanofilament on planar Ag/TiO2/Pt cells using visual observation. During the forming process, the filament tends to stay very thin. Specifically, it is so thin that it breaks up into a chain of nanospheres (according to Rayleigh instability) right after the formation has been completed. Similar mechanical breakup may also impact vertically stacked cells, causing reliability concerns.