Person:

Paulus, Geraldine

The vision for graphene and other two-dimensional electronics is the direct production of nanoelectronic circuits and barrier materials from a single precursor sheet. DNA origami and single-stranded tiles are powerful methods to encode complex shapes within a DNA sequence, but their translation to patterning other nanomaterials has been limited. Here we develop a metallized DNA nanolithography that allows transfer of spatial information to pattern two-dimensional nanomaterials capable of plasma etching. Width, orientation and curvature can be programmed by specific sequence design and transferred, as we demonstrate for graphene. Spatial resolution is limited by distortion of the DNA template upon Au metallization and subsequent etching. The metallized DNA mask allows for plasmonic enhanced Raman spectroscopy of the underlying graphene, providing information on defects, doping and lattice symmetry. This DNA nanolithography enables wafer-scale patterning of two-dimensional electronic materials to create diverse circuit elements, including nanorings, three- and four-membered nanojunctions, and extended nanoribbons.

Understanding the transcription factors that modulate epithelial resistance to injury is necessary for understanding intestinal homeostasis and injury repair processes. Recently, transcription factor EB (TFEB) was implicated in expression of autophagy and host defense genes in nematodes and mammalian cells. However, the in vivo roles of TFEB in the mammalian intestinal epithelium were not known. Here, we used mice with a conditional deletion of Tfeb in the intestinal epithelium (Tfeb ΔIEC) to examine its importance in defense against injury. Unperturbed Tfeb ΔIEC mice exhibited grossly normal intestinal epithelia, except for a defect in Paneth cell granules. Tfeb ΔIEC mice exhibited lower levels of lipoprotein ApoA1 expression, which is downregulated in Crohn’s disease patients and causally linked to colitis susceptibility. Upon environmental epithelial injury using dextran sodium sulfate (DSS), Tfeb ΔIEC mice exhibited exaggerated colitis. Thus, our study reveals that TFEB is critical for resistance to intestinal epithelial cell injury, potentially mediated by APOA1.