Significance One of the central goals of developmental biology and medicine is to ascertain the relationships between the genotype and phenotype of cells. Single-cell transcriptome analysis represents a powerful strategy to reach this goal. We advance these strategies to single nuclei from neural progenitor cells and dentate gyrus tissue, from which it is very difficult to recover intact cells. This provides a unique means to carry out RNA sequencing from individual neurons that avoids requiring isolation of single-cell suspensions, eliminating potential changes in gene expression due to enzymatic-cell dissociation methods. This method will be useful for analysis of processes occurring in the nucleus and for gene-expression studies of highly interconnected cells such as neurons.

Acidification of intracellular compartments by the vacuolar-type H1 -ATPases (VHA) is known to energize ion and metabolite transport, though cellular processes influenced by this activity are poorly understood. At least 26 VHA genes encode 12 subunits of the V 1 V o -ATPase complex in Arabidopsis, and how the expression, assembly, and activity of the pump are integrated into signaling networks that govern growth and adaptation are largely unknown. The role of multiple VHA-c genes encoding the 16-kD subunit of the membrane V o sector was investigated. Expression of VHA-c1, monitored by promoter-driven b-glucuronidase (GUS) activity was responsive to light or dark in an organ-specific manner. VHA-c1 expression in expanding cotyledons, hypocotyls of etiolated seedlings, and elongation zone of roots supported a role for V-ATPase in cell enlargement. Mutants reduced in VHA-c1 transcript using dsRNA-mediated interference showed reduction in root growth relative to wildtype seedlings. In contrast, VHA-c3 promoter::GUS expression was undetectable in most organs of seedlings, but strong in the root cap. Interestingly, dsRNA-mediated mutants of vha-c3 also showed reduced root length and decreased tolerance to moderate salt stress. The results suggest that V-ATPase functions in the root cap influenced root growth. Expression of VHA-c1 and VHA-c3 in tissues with active membrane flow, including root cap, vascular strands, and floral style would support a model for participation of the V o sector and V 1 V o -ATPase in membrane trafficking and fusion. Two VHA-c genes are thus differentially expressed to support growth in expanding cells and to supply increased demand for V-ATPase in cells with active exocytosis.From the perspective of physiologists and biochemists, it is well established that primary proton pumps are crucial for plant growth and survival. Among three distinct proton pumps, the most complex is the vacuolar-type H 1 -ATPase. Physiological and biochemical studies have demonstrated that acidification of the vacuolar compartment by this pump energizes the uptake and release of ions and metabolites (Sze et al., 1992;Lü ttge and Ratajczak, 1997). However, due to its structural complexity, we know very little about how the expression, assembly, and activity of this pump are integrated into the signaling networks that govern the life cycle of plants. In addition to its association with vacuolar membranes in plant cells, the pump has been localized to diverse subcellular membranes, including the Golgi (Ali and Akazawa, 1986; Matsuoka et al., 1997), endoplasmic reticulum (ER; Herman et al., 1994), intracellular vesicles, and the plasma membrane Schumacher et al., 1999;Dietz et al., 2001). Yet the specific subcellular functions of V-ATPases in distinct cell types and their consequences on a developing multicellular plant are largely unknown. Thus, from the perspectives of molecular, cell, and developmental biologists, many questions remain.Based on extensive biochemical and structural studies from animal, yeast and plant...

Magnetic nanoparticle-containing adhesive with DMAHDM and NACP under a magnetic force yielded much greater dentin bond strength than commercial control. The novel adhesive reduced biofilm CFU by 4 logs and increased the biofilm pH from a cariogenic pH 4.5-6.9, and therefore is promising to enhance the resin-tooth bond, strengthen tooth structures, and suppress secondary caries at the restoration margins.

Maintaining the vitality of the dental pulp, the highly innervated and highly vascular, innermost layer of the tooth, is a critical goal of any dental procedure. Upon injury, targeting the pulp with specific therapies is challenging because it is encased in hard tissues. This project describes a method that can effectively deliver therapeutic agents to the pulp. This method relies on the use of nanoparticles that can be actively steered using magnetic forces to the pulp, traveling through naturally occurring channels in the dentin (the middle layer of the tooth). This method can reduce the inflammation of injured pulp and improve the penetration of dental adhesives into dentin. Such a delivery method would be less expensive, and both less painful and less traumatic than existing therapeutic options available for treatment of injured dental pulp. This technique would be simple and could be readily translated to clinical use.

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