Abstract
Polyamines spermidine and spermine, and their diamine precursor putrescine, are essential for normal cellular functions in both pro- and eukaryotes. Cellular polyamine levels are regulated by biosynthesis, degradation and transport. Transport of dietary and luminal bacterial polyamines in gastrointestinal (GI) tissues plays a significant role in tissue polyamine homeostasis. We have reported that caveolin-1 play an inhibitory role in polyamine uptake in GI tissues. We investigated the mechanism of caveolin-1-regulated polyamine transport. We found that glutathione S-transferase Π(GSTΠ) was secreted from caveolin-1 knockdown cells and stimulated spermidine transport in human colon-derived HCT116 cells. GSTΠ secreted in the medium increased S-glutathionylated protein level in the plasma membrane fraction. Proteomic analysis revealed that actin was S-glutathionylated by GSTΠ. Immunofluorescence microscopy demonstrated that actin filaments around plasma membrane were S-glutathionylated in caveolin-1 knockdown cells. Inhibition of actin remodeling by jasplakinolide caused a decrease in polyamine uptake activity. These data support a model in which caveolin-1 negatively regulates polyamine uptake by inhibiting GSTΠ secretion, which stimulates actin remodeling and endocytosis.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 5713-5723 |
| Number of pages | 11 |
| Journal | Oncotarget |
| Volume | 10 |
| Issue number | 55 |
| State | Published - 2019 |
Keywords
- Actin
- Caveolin
- GSTπ
- Polyamine
- Transport
ASJC Scopus subject areas
- Oncology