Stress-specific p38 MAPK activation is sufficient to drive EGFR endocytosis but not its nuclear translocation

A Tomas, S Jones, SO Vaughan… - Journal of Cell …, 2017 - journals.biologists.com
A Tomas, S Jones, SO Vaughan, D Hochhauser, CE Futter
Journal of Cell Science, 2017journals.biologists.com
ABSTRACT EGF receptor (EGFR) endocytosis is induced by stress in a manner dependent
on the p38 MAPK family. Ligand and stresses such as X-rays, reportedly promote nuclear
trafficking of endocytosed EGFR for regulation of gene transcription and DNA repair. We fail
to detect EGFR endocytosis or nuclear transport following X-ray treatment of HeLa or head
and neck cancer cells, despite extensive DNA damage induction. Apparent nuclear staining
with EGFR extracellular domain antibody remained present despite reduced/absent EGFR …
Abstract
EGF receptor (EGFR) endocytosis is induced by stress in a manner dependent on the p38 MAPK family. Ligand and stresses such as X-rays, reportedly promote nuclear trafficking of endocytosed EGFR for regulation of gene transcription and DNA repair. We fail to detect EGFR endocytosis or nuclear transport following X-ray treatment of HeLa or head and neck cancer cells, despite extensive DNA damage induction. Apparent nuclear staining with EGFR extracellular domain antibody remained present despite reduced/absent EGFR expression, and so did not represent nuclear EGFR. UVB and UVC, but not X-ray or UVA, treatment induced p38 activation and EGFR endocytosis, although all of these stresses induced DNA damage, indicating that DNA damage alone is not sufficient to induce EGFR endocytosis. Increased reactive oxygen species (ROS) levels following UVB treatment, compared to that seen with X-rays, do not alone explain differences in p38 activation. UVB, like UVC, induced EGFR accumulation predominantly in perinuclear endosomes, rather than in the nucleus. Our morphological techniques identifying major changes in receptor distribution do not exclude the possibility that small but biologically relevant amounts of EGFR enter the nucleus. This study highlights the importance and limitations of morphological analyses of receptor distribution in understanding signaling outcome.
journals.biologists.com
以上显示的是最相近的搜索结果。 查看全部搜索结果