Related Experiment Video
Updated: Aug 6, 2026

In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
Suprabasal overexpression of beta-1 integrin is induced by bovine papillomavirus type 1
Brooke Cooper1, Nicole Brimer, Mark Stoler
1Institute of Pathology, Case Western Reserve University, 10900 Euclid Av., Cleveland, OH 44106, USA.
Abstract:
In a normal stratified squamous epithelium, beta1-integrin is expressed in basal epithelial cells. In BPV-induced fibropapillomas beta1-integrin is overexpressed and aberrantly localized, with uniform expression in the lower spinous layer, and sporadic expression within the mid-spinous region that co-localizes with expression of the viral E5 and E7 oncoproteins. In situ hybridization of fibropapillomas for beta1-integrin RNA revealed sporadic hybridization in the spinous layer, indicating transcriptional induction. Beta1-integrin expression in cultured keratinocytes requires exogenous EGF in the media, but this requirement is lost if E7 is expressed, and E7 was able to abrogate the EGF-requirement of normal keratinocytes for the activation of ERK and DNA synthesis. Within fibropapillomas, suprabasal expression of E5 and E7 correlated with suprabasal expression of beta1-integrin and PCNA, indicating that vegetative viral replication in the spinous layer correlated with the expression of E7 and beta1 integrin. The ability of BPV-1 E7 to support beta1-integrin expression and EGF independent DNA synthesis and the activation of ERK are the first biochemical correlates of its expression in keratinocytes.
More Related Videos
06:13Handling of the Cotton Rat in Studies for the Pre-clinical Evaluation of Oncolytic Viruses
Published on: November 24, 2014
07:56Generation of a Bovine Primary Enteroid-Derived Two-Dimensional Monolayer Culture System for Applications in Translational Biomedical Research
Published on: April 5, 2024
Related Concept Videos
Intracellular Signaling Affects Focal Adhesions
Some...
Rous Sarcoma Virus (RSV) and Cancer
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
Activation of Integrins
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
Mechanisms of Retrovirus-induced Cancers
Integrins
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Insulin Secretory Vesicles