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Updated: Aug 8, 2026

Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain
11:29

Isolation of Soluble and Insoluble PrP Oligomers in the Normal Human Brain

Published on: October 3, 2012

A novel hamster prion protein mRNA contains an extra exon: increased expression in scrapie

G Li1, D C Bolton

  • 1IBR/CSI Center for Developmental Neuroscience and Developmental Disabilities, Staten Island, NY 10314, USA.

Brain Research
|March 21, 1997
PubMed

Insights

Researchers identified a new exon in the hamster prion protein (PrP) gene. This exon regulates PrP gene expression, particularly in astrocytes, and its expression increases during scrapie prion disease.

Area of Science:

  • Neuroscience
  • Genetics
  • Molecular Biology

Background:

  • Prion protein (PrP) is the primary component of prions, the infectious agents responsible for fatal neurodegenerative diseases.
  • The PrP gene structure varies across species, with hamsters and humans possessing two exons, unlike mice, cattle, and sheep which have three.

Purpose of the Study:

  • To identify and characterize the missing exon in the hamster PrP gene.
  • To investigate the role of this newly identified exon in regulating PrP gene expression in hamsters, particularly in response to prion infection.

Main Methods:

  • Gene sequencing to identify the novel hamster PrP exon.
  • Quantitative analysis of PrP mRNA variants (with and without the new exon) in different brain regions.
  • Correlation analysis between PrP mRNA expression and glial fibrillary acidic protein (GFAP) mRNA expression in response to scrapie prion inoculation.

Main Results:

  • A new exon (exon 2) was identified in the hamster PrP gene, showing significant sequence homology to mouse and other species' exon 2.
  • PrP mRNA containing the new exon (mRNA[1+2+3]) was expressed at lower levels than mRNA without the exon (mRNA[1+3]) in normal hamster brain regions.
  • Scrapie prion inoculation led to increased expression of PrP mRNA[1+2+3] in the colliculi, correlating with GFAP mRNA expression, suggesting astrocyte involvement.

Conclusions:

  • The newly identified hamster PrP exon plays a regulatory role in cellular PrP expression.
  • The mRNA variant including exon 2 (mRNA[1+2+3]) may be preferentially expressed in hamster astrocytes.
  • This finding provides insights into the molecular mechanisms of PrP regulation during prion diseases.

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