Document Detail

Chromatin-bound NLS proteins recruit membrane vesicles and nucleoporins for nuclear envelope assembly via importin-α/β.
MedLine Citation:
PMID:  22847741     Owner:  NLM     Status:  MEDLINE    
The mechanism for nuclear envelope (NE) assembly is not fully understood. Importin-β and the small GTPase Ran have been implicated in the spatial regulation of NE assembly process. Here we report that chromatin-bound NLS (nuclear localization sequence) proteins provide docking sites for the NE precursor membrane vesicles and nucleoporins via importin-α and -β during NE assembly in Xenopus egg extracts. We show that along with the fast recruitment of the abundant NLS proteins such as nucleoplasmin and histones to the demembranated sperm chromatin in the extracts, importin-α binds the chromatin NLS proteins rapidly. Meanwhile, importin-β binds cytoplasmic NE precursor membrane vesicles and nucleoporins. Through interacting with importin-α on the chromatin NLS proteins, importin-β targets the membrane vesicles and nucleoporins to the chromatin surface. Once encountering Ran-GTP on the chromatin generated by RCC1, importin-β preferentially binds Ran-GTP and releases the membrane vesicles and nucleoporins for NE assembly. NE assembly is disrupted by blocking the interaction between importin-α and NLS proteins with excess soluble NLS proteins or by depletion of importin-β from the extract. Our findings reveal a novel molecular mechanism for NE assembly in Xenopus egg extracts.
Quanlong Lu; Zhigang Lu; Qinying Liu; Li Guo; He Ren; Jingyan Fu; Qing Jiang; Paul R Clarke; Chuanmao Zhang
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2012-07-31
Journal Detail:
Title:  Cell research     Volume:  22     ISSN:  1748-7838     ISO Abbreviation:  Cell Res.     Publication Date:  2012 Nov 
Date Detail:
Created Date:  2012-11-06     Completed Date:  2013-05-16     Revised Date:  2014-10-28    
Medline Journal Info:
Nlm Unique ID:  9425763     Medline TA:  Cell Res     Country:  England    
Other Details:
Languages:  eng     Pagination:  1562-75     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cell Cycle Proteins / metabolism
Chromatin / metabolism*
Guanine Nucleotide Exchange Factors / metabolism
HeLa Cells
Nuclear Envelope / metabolism*
Nuclear Localization Signals / metabolism*
Nuclear Pore Complex Proteins / metabolism*
Nuclear Proteins / genetics,  metabolism
Xenopus / genetics,  metabolism
Xenopus Proteins / metabolism
alpha Karyopherins / metabolism*
beta Karyopherins / metabolism*
ran GTP-Binding Protein / metabolism
Grant Support
BB/G001480/1//Biotechnology and Biological Sciences Research Council
Reg. No./Substance:
0/Cell Cycle Proteins; 0/Chromatin; 0/Guanine Nucleotide Exchange Factors; 0/Nuclear Localization Signals; 0/Nuclear Pore Complex Proteins; 0/Nuclear Proteins; 0/Xenopus Proteins; 0/alpha Karyopherins; 0/beta Karyopherins; 0/chc1 protein, Xenopus; EC GTP-Binding Protein

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Differences in activation of mouse hepcidin by dietary iron and parenterally administered iron dextr...
Next Document:  The controversial role of Sirtuins in tumorigenesis - SIRT7 joins the debate.