Epidermal growth factor receptors destined for the nucleus are internalized via a clathrin-dependent pathway

• Published in: Biochemical and biophysical research communications 2011-08, Vol.412 (2), p.341-346
• Main Authors: De Angelis Campos, Ana Carolina, Rodrigues, Michele Angela, de Andrade, Carolina, de Goes, Alfredo Miranda, Nathanson, Michael H., Gomes, Dawidson A.
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; Active Transport, Cell Nucleus; Animals; cell fractionation; Cell Line, Tumor; Cell Nucleus - enzymology; Cells, Cultured; Clathrin; Clathrin - genetics; Clathrin - metabolism; CYTOPLASM; dynamins; Dynamins - genetics; Dynamins - metabolism; epidermal growth factor; Epidermal Growth Factor - metabolism; Epidermal growth factor receptor; epidermal growth factor receptors; fluorescent antibody technique; FRACTIONATION; GROWTH FACTORS; hepatocytes; Hepatocytes - enzymology; Humans; image analysis; LIVER; Liver - enzymology; LIVER CELLS; MUTANTS; Mutation; Nuclear translocation; plasma membrane; Rats; Receptor, Epidermal Growth Factor - metabolism; RECEPTORS; RNA; RNA Interference; RNA, Small Interfering - genetics; small interfering RNA; STIMULATION; TRANSLOCATION
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2011.07.100

► EGF and its receptor translocates to the nucleus in liver cells. ► Real time imaging shows that EGF moves to the nucleus. ► EGF moves with its receptor to the nucleus. ► Dynamin and clathrin are necessary for EGFR nuclear translocation. The epidermal growth factor (EGF) transduces its actions via the EGF receptor (EGFR), which can traffic from the plasma membrane to either the cytoplasm or the nucleus. However, the mechanism by which EGFR reaches the nucleus is unclear. To investigate these questions, liver cells were analyzed by immunoblot of cell fractions, confocal immunofluorescence and real time confocal imaging. Cell fractionation studies showed that EGFR was detectable in the nucleus after EGF stimulation with a peak in nuclear receptor after 10min. Movement of EGFR to the nucleus was confirmed by confocal immunofluorescence and labeled EGF moved with the receptor to the nucleus. Small interference RNA (siRNA) was used to knockdown clathrin in order to assess the first endocytic steps of EGFR nuclear translocation in liver cells. A mutant dynamin (dynamin K44A) was also used to determine the pathways for this traffic. Movement of labeled EGF or EGFR to the nucleus depended upon dynamin and clathrin. This identifies the pathway that mediates the first steps for EGFR nuclear translocation in liver cells.