A C-terminal motif containing a PKC phosphorylation site regulates γ-Protocadherin-mediated dendrite arborization in the cerebral cortex in vivo.

The Pcdhg gene cluster encodes 22 γ-Protocadherin (γ-Pcdh) cell adhesion molecules that critically regulate multiple aspects of neural development, including neuronal survival, dendritic and axonal arborization, and synapse formation and maturation. Each γ-Pcdh isoform has unique protein domains-a homophilically interacting extracellular domain and a juxtamembrane cytoplasmic domain-as well as a C-terminal cytoplasmic domain shared by all isoforms. The extent to which isoform-specific versus shared domains regulate distinct γ-Pcdh functions remains incompletely understood.

A C-terminal motif containing a PKC phosphorylation site regulates γ-Protocadherin-mediated dendrite arborization in the cerebral cortex .

The gene cluster encodes 22 γ-Protocadherin (γ-Pcdh) cell adhesion molecules that critically regulate multiple aspects of neural development, including neuronal survival, dendritic and axonal arborization, and synapse formation and maturation. Each γ-Pcdh isoform has unique protein domains-a homophilically-interacting extracellular domain and a juxtamembrane cytoplasmic domain-as well as a C-terminal cytoplasmic domain shared by all isoforms. The extent to which isoform-specific shared domains regulate distinct γ-Pcdh functions remains incompletely understood.

γ-Protocadherins control synapse formation and peripheral branching of touch sensory neurons.

Light touch sensation begins with activation of low-threshold mechanoreceptor (LTMR) endings in the skin and propagation of their signals to the spinal cord and brainstem. We found that the clustered protocadherin gamma (Pcdhg) gene locus, which encodes 22 cell-surface homophilic binding proteins, is required in somatosensory neurons for normal behavioral reactivity to a range of tactile stimuli. Developmentally, distinct Pcdhg isoforms mediate LTMR synapse formation through neuron-neuron interactions and peripheral axonal branching through neuron-glia interactions.

Serotonin signaling by maternal neurons upon stress ensures progeny survival.

Germ cells are vulnerable to stress. Therefore, how organisms protect their future progeny from damage in a fluctuating environment is a fundamental question in biology. We show that in , serotonin released by maternal neurons during stress ensures the viability and stress resilience of future offspring.

CRISPR/Cas9 interrogation of the mouse Pcdhg gene cluster reveals a crucial isoform-specific role for Pcdhgc4.

The mammalian Pcdhg gene cluster encodes a family of 22 cell adhesion molecules, the gamma-Protocadherins (γ-Pcdhs), critical for neuronal survival and neural circuit formation. The extent to which isoform diversity-a γ-Pcdh hallmark-is required for their functions remains unclear. We used a CRISPR/Cas9 approach to reduce isoform diversity, targeting each Pcdhg variable exon with pooled sgRNAs to generate an allelic series of 26 mouse lines with 1 to 21 isoforms disrupted via discrete indels at guide sites and/or larger deletions/rearrangements.

A critical role for the nuclear protein Akirin2 in the formation of mammalian muscle in vivo.

Evolutionarily conserved Akirin nuclear proteins interact with chromatin remodeling complexes at gene enhancers and promoters, and have been reported to regulate cell proliferation and differentiation. Of the two mouse Akirin genes, Akirin2 is essential during embryonic development, with known in vivo roles in immune system function and the formation of the cerebral cortex. Here we demonstrate that Akirin2 is critical for mouse myogenesis, a tightly regulated developmental process through which myoblast precursors fuse to form mature skeletal muscle fibers.

An essential role for the nuclear protein Akirin2 in mouse limb interdigital tissue regression.

The regulation of interdigital tissue regression requires the interplay of multiple spatiotemporally-controlled morphogen gradients to ensure proper limb formation and release of individual digits. Disruption to this process can lead to a number of limb abnormalities, including syndactyly. Akirins are highly conserved nuclear proteins that are known to interact with chromatin remodelling machinery at gene enhancers.

Akirin2 is essential for the formation of the cerebral cortex.

Background: The proper spatial and temporal regulation of dorsal telencephalic progenitor behavior is a prerequisite for the formation of the highly-organized, six-layered cerebral cortex. Premature differentiation of cells, disruption of cell cycle timing, excessive apoptosis, and/or incorrect neuronal migration signals can have devastating effects, resulting in a number of neurodevelopmental disorders involving microcephaly and/or lissencephaly. Though genes encoding many key players in cortical development have been identified, our understanding remains incomplete.

Transient activation of microglia following acute alcohol exposure in developing mouse neocortex is primarily driven by BAX-dependent neurodegeneration.

Fetal alcohol exposure is the most common known cause of preventable mental retardation, yet we know little about how microglia respond to, or are affected by, alcohol in the developing brain in vivo. Using an acute (single day) model of moderate (3 g/kg) to severe (5 g/kg) alcohol exposure in postnatal day (P) 7 or P8 mice, we found that alcohol-induced neuroapoptosis in the neocortex is closely correlated in space and time with the appearance of activated microglia near dead cells. The timing and molecular pattern of microglial activation varied with the level of cell death.

Imaging microglia in brain slices and slice cultures.

Here we describe a method for imaging fluorescently labeled parenchymal microglia (MG) in excised neonatal or adult rodent brain tissue slices. Using multichannel confocal or two-photon time-lapse imaging, the approach affords real-time analyses of MG behaviors, including motility, migration, chemotaxis, proliferation, and phagocytosis in live brain tissues. The method is applicable to acutely prepared tissue slices from developing and adult rodents and to slice cultures derived from neonatal rodents, including transgenic and green fluorescent protein reporter mice.

Pharmacist-managed chronic obstructive pulmonary disease screening in a community setting.

Objectives: To implement a spirometry-based chronic obstructive pulmonary disease (COPD) screening in a community pharmacy chain, determine whether pharmacists can accurately perform spirometry screenings and interpret results, and determine whether performing screenings improved enrollment in smoking cessation programs.

Design: Prospective study.

Setting: Kroger pharmacies in the Cincinnati-Dayton Kroger Marketing Area and off-site screening events in Cincinnati, OH, from March to December 2010.

Preparation of rodent hippocampal slice cultures.

INTRODUCTIONRodent organotypic hippocampal slice cultures (OHSCs) provide an outstanding preparation of central nervous system tissue for exploring the dynamic structural and physiological features of neuronal and glial cells within their native three-dimensional environments. It is a straightforward matter to obtain tissue slices from neonatal rodents. These slices culture well for periods up to several weeks and are easy to manipulate, allowing for a variety of in vitro experimental models.

Dendritic arbors of developing retinal ganglion cells are stabilized by beta 1-integrins.

The architecture of dendritic arbors is a defining characteristic of neurons and is established through a sequential but overlapping series of events involving process outgrowth and branching, stabilization of the global pattern, and synapse formation. To investigate the roles of cadherins and beta1-integrins in maintaining the global architecture of the arbor, we used membrane permeable peptides and transfection with dominant-negative constructs to disrupt adhesion molecule function in intact chick neural retina at a stage when the architecture of the ganglion cell (RGC) arbor is established but synapse formation is just beginning. Inactivation of beta1-integrins induces rapid dendrite retraction, with loss of dynamic terminal filopodia followed by resorption of major branches.

Early activation, motility, and homing of neonatal microglia to injured neurons does not require protein synthesis.

Neuronal injury in CNS tissues induces a rapid activation and mobilization of resident microglia (MG). It is widely assumed that changes in gene expression drive the morphological transformation of MG and regulate their mobilization during activation. Here, we used acutely excised neonatal rat brain slices to test whether the morphological transformation and homing of MG to injured neurons requires gene expression and de novo protein synthesis.

Localization of synapsin-I and PSD-95 in developing postnatal rat cerebellar cortex.

The comparative localization of two prominent synaptic proteins, synapsin-I (Syn-I) and PSD-95, was investigated in slices of developing (P3-P21) rat cerebellar cortex using double- or triple-label fluorescence immunohistochemistry and confocal microscopy. During the first postnatal week, Syn-I and PSD-95 immunoreactive (IR) puncta were strongly concentrated in the Purkinje cell layer (PCL) where they circumscribed irregularly shaped PC somata, forming pericellular nests that likely correspond to early climbing fiber synapses. PSD-95 and Syn-I puncta also were found along the shafts and at the tips of growing PC dendrite branches labeled with calbindin.

Neural crest cell motility in valproic acid.

Neural crest cells (NCCs) exit the dorsal neural tube and migrate to sites where they form diverse tissues. Valproic acid (VPA) is an anticonvulsant drug that induces neural tube and related defects. Altered NCC migration and proliferation have been proposed as mechanisms of teratogenicity.

Juxtavascular microglia migrate along brain microvessels following activation during early postnatal development.

Some parenchymal microglia in mammalian brain tissues, termed "juxtavascular microglia," directly contact the basal lamina of blood vessels; however, the functional consequences of this unique structural relationship are unknown. Here we used a rat brain slice model of traumatic brain injury to investigate the dynamic behavior of juxtavascular microglia following activation. Juxtavascular microglia were identified by confocal 3D reconstruction in tissue slices stained with a fluorescent lectin (FITC-IB4) that labels both microglia and blood vessel endothelial cells.