Neuronal diversity and convergence in a visual system developmental atlas.

Deciphering how neuronal diversity is established and maintained requires a detailed knowledge of neuronal gene expression throughout development. In contrast to mammalian brains, the large neuronal diversity of the Drosophila optic lobe and its connectome are almost completely characterized. However, a molecular characterization of this neuronal diversity, particularly during development, has been lacking.

Phenotypic Convergence: Distinct Transcription Factors Regulate Common Terminal Features.

Transcription factors regulate the molecular, morphological, and physiological characteristics of neurons and generate their impressive cell-type diversity. To gain insight into the general principles that govern how transcription factors regulate cell-type diversity, we used large-scale single-cell RNA sequencing to characterize the extensive cellular diversity in the Drosophila optic lobes. We sequenced 55,000 single cells and assigned them to 52 clusters.

Neural stem cells from mouse strain Thy1 YFP-16 are a valuable tool to monitor and evaluate neuronal differentiation and morphology.

To analyse events following transplantation of stem cells in the brain robust tools for tracing stem cells are required. Here we took advantage of the mouse strain B6.Cg-Tg(Thy1-YFP)16Jrs/J (Thy1 YFP-16), where yellow fluorescent protein (YFP) is under control of the promoter of Thy1 gene.

STAM2, a member of the endosome-associated complex ESCRT-0 is highly expressed in neurons.

STAM2 (signal transducing adaptor molecule 2), a subunit of the ESCRT-0 complex, is an endosomal protein acting as a regulator of receptor signaling and trafficking. To analyze STAM2 in the nervous system, its gene expression and protein localization in the mouse brain were identified using three methods: mRNA in situ hybridization, immunohistochemistry, and via lacZ reporter in frame with Stam2 gene using the gene trap mouse line Stam2(Gt1Gaj). STAM2 intracellular localization was analyzed by subcellular fractionation and co-immunofluorescence using confocal microscopy.

Krüppel-like transcription factor 8 (Klf8) is expressed and active in the neurons of the mouse brain.

Krüppel-like transcription factor 8 (KLF8) is a transcription factor suggested to be involved in various cellular events, including malignant cell transformation, still its expression in the adult rodent brain remained unknown. To analyze Klf8 in the mouse brain and to identify cell types expressing it, a specific transgenic Klf8(Gt1Gaj) mouse was used. The resulting Klf8 gene-driven β-galactosidase activity was visualized by X-gal histochemical staining of the brain sections.

Immunohistochemical expression of STAM2 in gastrointestinal stromal tumors.

Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract, believed to originate from the interstitial cells of Cajal or their stem cell-like precursors. Recent studies incidentally found the expression in interstitial cells of Cajal of the signal-transducing adaptor molecule-2 (STAM2), which is an endosomal protein acting as a regulator of receptor signaling and trafficking. Here, we investigated the immunohistochemical expression of STAM2 in GIST.

Murine neural crest stem cells and embryonic stem cell-derived neuron precursors survive and differentiate after transplantation in a model of dorsal root avulsion.

Spinal root avulsion results in paralysis and sensory loss, and is commonly associated with chronic pain. In addition to the failure of avulsed dorsal root axons to regenerate into the spinal cord, avulsion injury leads to extensive neuroinflammation and degeneration of second-order neurons in the dorsal horn. The ultimate objective in the treatment of this condition is to counteract degeneration of spinal cord neurons and to achieve functionally useful regeneration/reconnection of sensory neurons with spinal cord neurons.

Stam2 expression pattern during embryo development.

STAM2 is a tyrosine-phosphorylated protein suggested to be involved in cargo selection during endocytic pathway, regulation of exocytosis and intracellular signaling. Gene trap method was used to create via insertional mutagenesis a mutant mouse line with integration of promoterless βgeo (lacZ-neomycin phosphotransferase fusion) gene in the second intron of Stam2 gene, enabling analysis of its in vivo expression and function. The inserted β-galactosidase (lacZ) reporter gene was used to reveal Stam2 expression during development.

Neurons and a subset of interstitial cells of Cajal in the enteric nervous system highly express Stam2 gene.

Signal transducing adaptor molecule 2 (STAM2) is a phosphotyrosine protein, which is a member of the endosomal sorting complex required for transport (ESCRT-0) and is involved in the sorting process of the mono-ubiquitinated endosomal cargo for degradation in the lysosome. Analysis of gene trap mice carrying lacZ in frame with Stam2 revealed beta-galactosidase activity in the enteric nervous system (both in the myenteric and submucosal plexus) throughout the digestive tract. STAM2 immunostaining confirmed that the observed beta-galactosidase activity coincided with high Stam2 expression.

Spectrophotometric analysis of flavonoid-DNA interactions and DNA damaging/protecting and cytotoxic potential of flavonoids in human peripheral blood lymphocytes.

The ability of luteolin, kaempferol and apigenin to bind to calf thymus (ct)-DNA, mode of action and stability of flavonoids in buffer were investigated. Spectrophotometric analysis revealed a rapid degradation of apigenin in an aqueous medium, while kaempferol and luteolin were stable for 24h upon dissolution in water. Spectrophotometric study of the interactions of kaempferol and luteolin with calf thymus DNA suggests classic intercalation as their dominant binding mode to DNA.