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In situ Subcellular Fractionation of Adherent and Non-adherent Mammalian Cells
Published on: July 23, 2010
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A Ran-binding protein facilitates nuclear import of human papillomavirus type 16.
Kun-Yi Lai1,2, Matteo Rizzato1, Inci Aydin1
1Institute of Cellular Virology, Westphalian Wilhelms-University of Münster, Münster, Germany.
Plos Pathogens
|May 11, 2021
Summary
Human papillomaviruses (HPVs) use a unique nuclear import pathway. Researchers identified a novel protein complex involving RanBP10, KPNA2, and DYNLT3 that facilitates viral DNA transport during mitosis.
Area of Science:
- Virology
- Cell Biology
- Molecular Biology
Background:
- Human papillomaviruses (HPVs) exhibit an unusual nuclear import mechanism.
- The viral subviral complex (L2/vDNA) is transported to the nucleus post-mitosis, associating with chromatin.
Purpose of the Study:
- To identify cellular proteins involved in the nuclear import of the HPV L2/vDNA complex.
- To elucidate the mechanism of viral genome tethering to mitotic chromatin.
Main Methods:
- Label-free mass spectrometry
- Biochemical assays
- Microscopy
- Functional virological assays
Main Results:
- Discovered a novel protein complex comprising Ran-binding protein 10 (RanBP10), karyopherin alpha2 (KPNA2), and dynein light chain DYNLT3.
- Demonstrated that this complex facilitates the transport of the L2/vDNA complex towards mitotic chromatin.
Conclusions:
- Identified novel cellular interactors crucial for a poorly understood step in HPV entry.
- Characterized a new cellular transport complex involved in viral nuclear import.
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