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Published on: October 23, 2016
Nuclear functions of endocytic proteins
Iwona Pilecka1, Magdalena Banach-Orlowska, Marta Miaczynska
1International Institute of Molecular and Cell Biology, Laboratory of Cell Biology, 4 Ks. Trojdena Street, 02-109 Warsaw, Poland.
European Journal of Cell Biology
|June 23, 2007
Summary
Proteins involved in clathrin-mediated endocytosis exhibit dual functions, acting in both the cytoplasm and nucleus. These endocytic proteins can influence gene transcription, impacting cellular processes like growth and homeostasis.
Area of Science:
- Cell Biology
- Molecular Biology
- Signaling Networks
Background:
- Proteins can possess multiple, distinct functions within a cell, a phenomenon known as moonlighting.
- Proteins regulating clathrin-mediated endocytosis have recently been identified to exhibit such moonlighting properties.
Purpose of the Study:
- To explore the dual roles of endocytic proteins in both cytoplasmic and nuclear functions.
- To investigate the implications of nucleocytoplasmic shuttling of endocytic proteins on gene transcription and cellular signaling.
Main Methods:
- Analysis of protein localization and interactions within cellular compartments.
- Investigation of nucleocytoplasmic transport mechanisms for endocytic proteins.
- Assessment of the impact of endocytic proteins on gene expression modulation.
Main Results:
- Endocytic proteins, including clathrin adaptors and endosomal proteins, shuttle between the nucleus and cytoplasm.
- These proteins can associate with nuclear molecules, altering their activity and potentially modulating gene transcription.
- Nuclear roles of proteins like Eps15, Epsin1, and beta-arrestins contribute to complex signaling networks.
Conclusions:
- Endocytic proteins possess nuclear functions that extend beyond their cytoplasmic roles in endocytosis.
- These dual functions contribute significantly to cellular homeostasis, growth, and proliferation.
- Further research is needed to elucidate the precise mechanisms of nuclear-cytoplasmic interplay and signaling roles.
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