The mRNA encoding the scrapie agent protein is present in a variety of non-neuronal cells

Abstract

PrP 27-30, a unique protease-resistant protein associated with scrapie infectivity, derives from the proteolytic cleavage of a larger precursor encoded by a host gene. To identify sites of PrP biosynthesis, in situ hybridization was done using cloned PrP cDNA as a probe. In rodent brain, PrP mRNA was expressed in neurons, ependymal cells, choroid plexus epithelium, astrocytes, pericytes, endothelial cells and meninges of both scrapie-infected and uninfected animals. PrP mRNA was also detected in vitro in isolated brain microglia cells. Pulmonary cells and heart muscle cells contained high levels of this mRNA. Hybridization was not detected in spleen, confirming earlier RNA blot experiments indicating extremely low levels of PrP mRNA in this tissue. Results indicate that PrP mRNA is a normal component in a variety of non-neuronal tissues and may explain the origin of the amyloid plaques present in the subependymal region of scrapie-infected brain.

Motor neuron cell-nonautonomous rescue of spinal muscular atrophy phenotypes in mild and severe transgenic mouse models

“…Gavrilina et al (2008) reported that a small increase of SMN in neurons strikingly extended the survival of severe SMA mice carrying an SMN cDNA transgene driven by a neuronspecific promoter. However, the mouse prion promoter used in that study is also active in many nonneuronal cell types and peripheral tissues (Brown et al 1990), which may have contributed to phenotypic rescue. Indeed, several recent studies using various mouse models showed that restoring SMN expression only in motor neurons or pan-neuronally resulted in a limited survival increase (Gogliotti et al 2012;Lee et al 2012;Martinez et al 2012).…”

Epithelial and endothelial expression of the green fluorescent protein reporter gene under the control of bovine prion protein (PrP) gene regulatory sequences in transgenic mice

“…Total RNA was extracted and purified with the RNA NOW kit (Biogenetex, Seabrook, TX) as recommended by the supplier. For cDNA synthesis, 2 g of total RNA was heat-denatured for 3 min at 70°C and reverse-transcribed with 200 units of Superscript II RNaseH Ϫ Reverse Transcriptase (Life Technologies, Paisley, Scotland) in 20 l of 1ϫ incubation buffer (provided by the supplier) supplemented with 10 mM DTT, 1 mM dNTP, 1 unit͞ l RNAsin (Promega), and 0.5 g of (dT) [12][13][14][15][16][17][18] primers (Amersham Pharmacia). Two microliters of each cDNA reaction was subjected to PCR amplification with 25 pmol each of the sense and antisense primers in 50 l 1ϫ PCR buffer, 0.2 mM dNTP, and 1 unit recombinant Taq DNA polymerase (Life Technologies).…”

“…The PrP c gene has been described as a housekeeping gene with a preferential expression in neurons (13)(14)(15). PrP c has been shown to be present in various regions of the hamster brain, including cortex, hippocampus, striatum, olfactory bulb, hypothalamus, midbrain, cerebellum, and brainstem (14).…”

“…PrP c gene expression has also been documented at the cellular level by in situ hybridization (20,21) and immunohistochemistry. The mRNA encoding PrP c has been shown to be present in the ependymal cells, the epithelial cells of the choroid plexus (13), and the glial cells of the CNS (22). However, in peripheral organs, the identification of PrP cexpressing cells is much less documented than in the brain.…”

“…However, in peripheral organs, the identification of PrP cexpressing cells is much less documented than in the brain. In hamster, PrP c protein has been found to be present in pneumocytes, in parietal and enteroendocrine cells of the stomach (14), and in cardiomyocytes (13). PrP c also has been detected on the surface of lymphocytes and of activated T lymphocytes in humans and mice (23,24) and at higher levels on follicular dendritic cells (25).…”