By using proteolysis, recombinant mutant proteins, or synthetic peptides and by testing these reagents in liquid phase binding or nuclear import assays, we have mapped binding regions of karyopherin alpha. We found that the C-terminal region of karyopherin alpha recognizes the nuclear localization sequence (NLS), whereas its N-terminal region binds karyopherin beta. Surprisingly, karyopherin alpha also contains an NLS. Thus, karyopherin alpha belongs to a group of proteins that contain both a ligand (NLS) and a cognate receptor (NLS recognition site) in one molecule with a potential for autologous ligand-receptor interactions. The NLS of karyopherin alpha overlaps with the binding site of karyopherin alpha for karyopherin beta. Hence, binding of karyopherin beta to karyopherin alpha covers the NLS of karyopherin alpha. This prevents autologous ligand receptor interactions and explains the observed cooperative binding of karyopherin alpha to a heterologous NLS protein in the presence of karyopherin beta.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC39066 | PMC |
http://dx.doi.org/10.1073/pnas.93.13.6572 | DOI Listing |
J Cell Biol
January 2025
Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, NC, USA.
Controlling biomolecular condensate formation within the nucleus is critical for genome function. In this issue, Xu et al. (https://doi.
View Article and Find Full Text PDFJ Virol
December 2024
School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia.
Adeno-associated viruses (AAVs) are the most extensively researched viral vectors for gene therapy globally. The AAV viral protein 1 (VP1) N-terminus controls the capsid's ability to translocate into the cell nucleus; however, the exact mechanism of this process is largely unknown. In this study, we sought to elucidate the precise interactions between AAV serotype 6 (AAV6), a promising vector for immune disorders, and host transport receptors responsible for vector nuclear localization.
View Article and Find Full Text PDFAnn Med
December 2024
Department of Andrology, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou, China.
J Cell Biol
January 2025
Department of General Intensive Care Unit and Department of Biochemistry of the Second Affiliated Hospital, Liangzhu Laboratory, Zhejiang University School of Medicine, Hangzhou, China.
The histone locus body (HLB) is a membraneless organelle that determines the transcription of replication-dependent histones. However, the mechanisms underlying the appropriate formation of the HLB in the nucleus but not in the cytoplasm remain unknown. HLB formation is dependent on the scaffold protein NPAT.
View Article and Find Full Text PDFACS Infect Dis
December 2024
Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana 500039, India.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!