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Published on: September 7, 2010
N-acetylglucosaminyltransferase V modifies TrKA protein, regulates the receptor function
Xiaoyun Yang1, Jing Li, Meiyu Geng
1Department of Molecular Pharmacology, Marine Drug and Food Institute, Ocean University of China, Qingdao, P.R. China. yang_xiaoyun@yahoo.com
Cellular and Molecular Neurobiology
|March 18, 2008
Summary
N-acetylglucosaminyltransferase V (GnT-V) modifies the TrkA receptor, enhancing nerve growth factor signaling and promoting axon outgrowth. This suggests GnT-V plays a key role in neuronal differentiation and offers therapeutic potential.
Area of Science:
- Glycobiology
- Neuroscience
- Cell Biology
Background:
- N-acetylglucosaminyltransferases V (GnT-V) are crucial for N-linked glycoprotein processing in the Golgi apparatus.
- The TrkA receptor, a tyrosine kinase, mediates the effects of nerve growth factor (NGF).
Purpose of the Study:
- To investigate if GnT-V modifies TrkA and influences its function.
- To explore the role of GnT-V in NGF-induced neuronal differentiation.
Main Methods:
- PC12 cells were transfected with GnT-V or control plasmids.
- Protein expression and modification were analyzed using Western blot and immunoprecipitation.
- TrkA receptor endocytosis was assessed via receptor internalization assays.
Main Results:
- Overexpression of GnT-V directly modified TrkA protein.
- GnT-V enhanced NGF-induced axon outgrowth in PC12 cells, even at low NGF doses.
- TrkA modification by GnT-V increased NGF-activated autophosphorylation in vitro.
- GnT-V overexpression delayed TrkA receptor endocytosis.
Conclusions:
- GnT-V directly modifies TrkA, enhancing its function and promoting NGF-mediated neuronal differentiation.
- GnT-V appears to play an endogenous role in regulating NGF receptor function.
- Targeting glycosyltransferases like GnT-V may offer novel therapeutic strategies.
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