N-ethylmaleimide-sensitive factor is associated with the nuclear envelope
J Mashima1, M Nagahama, K Hatsuzawa
1School of Life Science, Tokyo University of Pharmacy and Life Science, Horinouchi, Hachioji, Tokyo, 192-0392, Japan.
Biochemical and Biophysical Research Communications
|July 29, 2000
Summary
N-Ethylmaleimide-sensitive factor (NSF), an ATPase crucial for membrane fusion, binds differently to the nuclear envelope during the cell cycle. Its association with nuclear membranes changes, becoming ATP-dependent during mitosis.
Area of Science:
- Cell Biology
- Molecular Biology
- Membrane Trafficking
Background:
- N-Ethylmaleimide-sensitive factor (NSF) is a critical ATPase.
- NSF plays a key role in exocytic and endocytotic membrane fusion events.
- NSF functions by disassembling complexes involving soluble NSF attachment proteins (SNAPs) and SNAP receptors (SNAREs).
Purpose of the Study:
- To investigate the association of NSF with the nuclear envelope.
- To determine if NSF's binding to the nuclear envelope changes during the cell cycle.
- To understand the regulation of NSF at the nuclear membrane.
Main Methods:
- Biochemical assays to study protein complex disassembly.
- Incubation of isolated membranes with Mg(2+)-ATP.
- Analysis of NSF release from Golgi and nuclear membranes in interphase and mitotic cells.
Main Results:
- Golgi-associated NSF was released from membranes by Mg(2+)-ATP.
- Nuclear envelope-associated NSF in interphase cells was resistant to Mg(2+)-ATP treatment.
- Nuclear envelope-associated NSF was released by Mg(2+)-ATP during mitosis.
Conclusions:
- NSF associates with the nuclear envelope in a cell cycle-dependent manner.
- The binding mode of nuclear membrane-associated NSF differs between interphase and mitosis.
- These findings suggest a regulatory role for NSF at the nuclear envelope during cell division.
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