当前位置： SCI文献检索 > JOURNAL OF CELLULAR PHYSIOLOGY期刊下所有文献 > Novel biphasic traffic of endocytosed EGF to recycling and degradative compartments in lacrimal gland acinar cells.

Novel biphasic traffic of endocytosed EGF to recycling and degradative compartments in lacrimal gland acinar cells.

Abstract：

:The purpose of this study was to delineate the traffic patterns of EGF and EGF receptors (EGFR) in primary cultured acinar epithelial cells from rabbit lacrimal glands. Uptake of [(125)I]-EGF exhibited saturable and non-saturable, temperature-dependent components, suggesting both receptor-mediated and fluid phase endocytosis. Accumulation of [(125)I] was time-dependent over a 120-min period, but the content of intact [(125)I]-EGF decreased after reaching a maximum at 20 min. Analytical fractionation by sorbitol density gradient centrifugation and phase partitioning indicated that within 20 min at 37 degrees C [(125)I] reached an early endosome, basal-lateral recycling endosome, pre-lysosome, and lysosome. Small components of the label also appeared to reach the Golgi complex and trans-Golgi network. Intact [(125)I]-EGF initially accumulated in the recycling endosome; the content in the recycling endosome subsequently decreased, and by 120 min increased amounts of [(125)I]-labeled degradation products appeared in the pre-lysosomes and lysosomes. Confocal microscopy imaging of FITC-EGF and LysoTrackerRed revealed FITC enriched in a dispersed system of non-acidic compartments at 20 min and in acidic compartments at 120 min. Both confocal immunofluorescence microscopy and analytical fractionation indicated that the intracellular EGFR pool was much larger than the plasma membrane-expressed pool at all times. Cells loaded with [(125)I]-EGF released a mixture of intact EGF and [(125)I]-labeled degradation products. The observations indicate that in lacrimal acinar cells, EGFR and EGF-EGFR complexes continually traffic between the plasma membranes and a system of endomembrane compartments; EGF-stimulation generates time-dependent signals that initially decrease, then increase, EGF-EGFR traffic to degradative compartments.

journal_name

J Cell Physiol

journal_title

Journal of cellular physiology

authors

Xie J,Qian L,Wang Y,Rose CM,Yang T,Nakamura T,Hamm-Alvarez SF,Mircheff AK

doi

10.1002/jcp.10458

keywords:

subject

Has Abstract

pub_date

2004-04-01 00:00:00

pages

108-25

issue

eissn

0021-9541

issn

1097-4652

journal_volume

199

pub_type

杂志文章

在线工具

Novel biphasic traffic of endocytosed EGF to recycling and degradative compartments in lacrimal gland acinar cells.