PUBLICATION
Expression of zTOR-associated microRNAs in zebrafish embryo treated with rapamycin
- Authors
- Khor, E.S., Noor, S.M., Wong, P.F.
- ID
- ZDB-PUB-160227-3
- Date
- 2016
- Source
- Life sciences 150: 67-75 (Journal)
- Registered Authors
- Keywords
- Aging, Embryonic development, Mammalian target of rapamycin, Zebrafish
- MeSH Terms
-
- Aging/genetics
- Alkaline Phosphatase/metabolism
- Animals
- Down-Regulation/drug effects
- Embryo, Nonmammalian
- Melanocytes/drug effects
- MicroRNAs/biosynthesis*
- MicroRNAs/drug effects
- MicroRNAs/genetics
- Neovascularization, Physiologic/genetics
- Sirolimus/pharmacology*
- Transcription Factors/biosynthesis*
- Transcription Factors/genetics
- Zebrafish
- Zebrafish Proteins/biosynthesis*
- Zebrafish Proteins/genetics
- beta-Galactosidase/biosynthesis
- beta-Galactosidase/genetics
- PubMed
- 26916825 Full text @ Life Sci.
Citation
Khor, E.S., Noor, S.M., Wong, P.F. (2016) Expression of zTOR-associated microRNAs in zebrafish embryo treated with rapamycin. Life sciences. 150:67-75.
Abstract
Aims MicroRNAs (miRNAs) are vital in modulating lifespan and various biological processes including vascular function. The pivotal roles of mammalian target of rapamycin (mTOR) in regulating senescence and angiogenesis have been extensively described. However, the roles of its orthologue, zebrafish target of rapamycin (zTOR) in senescence and angiogenesis remain to be unravelled. In the present study, we aimed to investigate the role of zTOR and identify miRNAs associated with senescence and angiogenesis.
Main methods Zebrafish embryos were treated with rapamycin and the inhibition of zTOR and its downstream proteins were validated by immunoblotting. Following the treatment, melanocyte density was quantitated, and senescence and angiogenic responses were determined by senescence-associated beta-galactosidase (SA-β-gal) and endogenous alkaline phosphatase (ALP) staining, respectively. Relative expression of microRNAs were determined by quantitative RT-PCR.
Key findings Rapamycin (400nM) suppressed zTOR pathway by down-regulating the phosphorylation of zTOR-associated proteins such as P70S6K and S6K at both 4h post-fertilisation (hpf) and 8hpf while 4E-BP1 was only down-regulated at 8hpf when compared to their respective vehicle controls. Treatment with rapamycin also resulted in significant suppression of melanocyte development and senescence-associated beta-galactosidase (SA-β-gal) activity, and perturbed the development of intersegmental vessels (ISVs) of zebrafish embryos. In addition, the expressions of dre-miR-9-5p and -3p, dre-miR-25-3p and dre-miR-124-3p were significantly up-regulated in embryos treated with rapamycin from 4hpf.
Significance Our findings suggest the involvement of zTOR in embryonic senescence and angiogenesis which could be potentially mediated by selected miRNAs.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping