In:
Traffic, Wiley, Vol. 2, No. 4 ( 2001-04), p. 277-296
Abstract:
We have investigated the transport and canalicular enrichment of fluorescent phosphatidylcholine (PC) in HepG2 cells using the fluorescent analogs of PC C6‐NBD‐PC and β‐BODIPY‐PC. Fluorescent PC was efficiently transported to the biliary canaliculus (BC) and became enriched on the lumenal side of the canalicular membrane as shown for C6‐NBD‐PC. Some fluorescent PC was transported in vesicles to a subapical compartment (SAC) or apical recycling compartment (ARC) in polarized HepG2 cells as shown by colocalization with fluorescent sphingomyelin (C6‐NBD‐SM) and fluorescent transferrin, respectively. Extensive trafficking of vesicles containing fluorescent PC between the basolateral domain, the SAC/ARC and the BC as well as endocytosis of PC analogs from the canalicular membrane were found. Evidence for nonvesicular transport included enrichment of the PC‐analog β‐BODIPY‐PC in the BC (t 1/2 = 3.54 min) prior to its accumulation in the SAC/ARC (t 1/2 = 18.5 min) at 37 °C. Transport of fluorescent PC to the canalicular membrane also continued after disruption of the actin or microtubule cytoskeleton and at 2 °C. These results indicate that: (i) a nonvesicular transport pathway significantly contributes to the canalicular enrichment of PC in hepatocytic cells, and (ii) vesicular transport of fluorescent PC occurs from both membrane domains via the SAC/ARC.
Type of Medium:
Online Resource
ISSN:
1398-9219
,
1600-0854
DOI:
10.1034/j.1600-0854.2001.9o135.x
Language:
English
Publisher:
Wiley
Publication Date:
2001
detail.hit.zdb_id:
2020962-9
detail.hit.zdb_id:
1483852-7
SSG:
12
