The binding site of karyopherin alpha for karyopherin beta overlaps with a nuclear localization sequence.

Proc Natl Acad Sci U S A

Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockfeller University, New York, NY 10021, USA.

Published: June 1996

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/PMC39066PMC
http://dx.doi.org/10.1073/pnas.93.13.6572DOI Listing

Publication Analysis

Top Keywords

karyopherin alpha
40
karyopherin beta
20
karyopherin
15
nls karyopherin
12
alpha
10
binding site
8
site karyopherin
8
alpha karyopherin
8
nuclear localization
8
localization sequence
8

Similar Publications

Directed stochasticity: Building biomolecular condensates in the right place.

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 PDF

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 PDF
Article Synopsis
  • * Researchers analyzed various datasets using advanced techniques to identify potential biomarkers, leading to the discovery of 77 progression-associated genes, with KPNA2 identified as a significant risk factor linked to poor outcomes.
  • * KPNA2 was found to be overexpressed in aggressive ACC cases, promoting cancer cell growth and suppressing immune response, indicating its potential as a key biomarker for predicting patient prognosis and treatment effectiveness.
View Article and Find Full Text PDF

KPNA3 regulates histone locus body formation by modulating condensation and nuclear import of NPAT.

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 PDF
Article Synopsis
  • * Researchers identified a specific nuclear localization signal (NLS) in LISP2, which is unique to the parasite and its close relative, indicating a possible evolutionary adaptation to their primate hosts.
  • * Functional tests show that this NLS is essential for transporting LISP2 into the nucleus, with the involvement of importin-α/β proteins being crucial, while LISP2 does not have a mechanism for leaving the nucleus once inside.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!