Abstract |
Solid tumor development is frequently accompanied by energy-deficient conditions such as glucose deprivation and hypoxia. Follistatin (FST), a secretory protein originally identified from ovarian follicular fluid, has been suggested to be involved in tumor development. However, whether it plays a role in cancer cell survival under energy-deprived conditions remains elusive. In this study, we demonstrated that glucose deprivation markedly enhanced the expression and nucleolar localization of FST in HeLa cells. The nucleolar localization of FST relied on its nuclear localization signal (NLS) comprising the residues 64-87. Localization of FST to the nucleolus attenuated rRNA synthesis, a key process for cellular energy homeostasis and cell survival. Overexpression of FST delayed glucose deprivation-induced apoptosis, whereas down-regulation of FST exerted the opposite effect. These functions depended on the presence of an intact NLS because the NLS-deleted mutant of FST lost the rRNA inhibition effect and the cell protective effect. Altogether, we identified a novel nucleolar function of FST, which is of importance in the modulation of cancer cell survival in response to glucose deprivation.
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Authors | Xiangwei Gao, Saisai Wei, Kairan Lai, Jinghao Sheng, Jinfeng Su, Junqiao Zhu, Haojie Dong, Hu Hu, Zhengping Xu |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 285
Issue 47
Pg. 36857-64
(Nov 19 2010)
ISSN: 1083-351X [Electronic] United States |
PMID | 20843798
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- FST protein, human
- Follistatin
- Nuclear Localization Signals
- RNA, Messenger
- RNA, Ribosomal
- RNA, Small Interfering
- Glucose
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Topics |
- Apoptosis
- Blotting, Northern
- Blotting, Western
- Cell Nucleolus
(metabolism)
- Chromatin Immunoprecipitation
- Down-Regulation
- Female
- Fluorescent Antibody Technique
- Follistatin
(antagonists & inhibitors, genetics, metabolism)
- Glucose
(deficiency)
- HeLa Cells
- Humans
- Nuclear Localization Signals
- RNA, Messenger
(genetics)
- RNA, Ribosomal
(antagonists & inhibitors, biosynthesis)
- RNA, Small Interfering
(genetics)
- Reverse Transcriptase Polymerase Chain Reaction
- Uterine Cervical Neoplasms
(metabolism, pathology)
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