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Updated: Aug 8, 2026
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Monitoring eIF4F Assembly by Measuring eIF4E-eIF4G Interaction in Live Cells
Published on: May 1, 2020
Translational control by neuroguidin, a eukaryotic initiation factor 4E and CPEB binding protein
Mi-Young Jung1, Lori Lorenz, Joel D Richter
1Program in Molecular Medicine, University of Massachusetts Medical School, Suite 204, 373 Plantation St., Worcester MA 01605, USA.
Molecular and Cellular Biology
|May 18, 2006
Summary
Neuroguidin (Ngd) is a novel protein that binds eukaryotic initiation factor 4E (eIF4E) and regulates translation. Ngd is crucial for neural development, guiding neural tube closure and neural crest cell migration.
Area of Science:
- Neuroscience
- Molecular Biology
- Developmental Biology
Background:
- Cytoplasmic polyadenylation element (CPE)-dependent polyadenylation and translation are vital for early development and neuronal plasticity.
- Eukaryotic initiation factor 4E (eIF4E) is a key regulator of cap-dependent translation.
Purpose of the Study:
- To identify and characterize a novel eIF4E-binding protein involved in translational regulation.
- To investigate the role of this protein, Neuroguidin (Ngd), in neural development.
Main Methods:
- Protein interaction studies to confirm Ngd binding to eIF4E and CPEB.
- Xenopus oocyte and embryo assays to assess Ngd's translational repression activity and developmental functions.
- Morpholino-based knockdown and mRNA rescue experiments in Xenopus embryos.
Main Results:
- Neuroguidin (Ngd) directly binds to eukaryotic initiation factor 4E (eIF4E) via three distinct motifs.
- Ngd binds to CPEB and represses translation in a CPE-dependent manner in Xenopus oocytes.
- Knockdown of Ngd in Xenopus embryos disrupts neural tube closure and neural crest migration, which can be rescued by Ngd mRNA injection.
Conclusions:
- Neuroguidin (Ngd) is a novel eIF4E-binding protein that regulates translation.
- Ngd plays a critical role in guiding neural development by controlling the translation of CPE-containing mRNAs.
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First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
02:33Initiation of Translation
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First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
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01:29Translational Regulation
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