國立高雄大學圖資館 |

Language: English

Back

The dual role of FG nucleoporins in ...

Patel, Samir Sharad.

The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes.

Record Type:	Electronic resources : Monograph/item
Title/Author:	The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes.
Author:	Patel, Samir Sharad.
Description:	140 p.
Notes:	Adviser: Michael Rexach.
Notes:	Source: Dissertation Abstracts International, Volume: 66-08, Section: B, page: 4040.
Contained By:	Dissertation Abstracts International66-08B.
Subject:	Biology, Cell.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3186373
ISBN:	9780542286490

The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes.
Patel, Samir Sharad.

The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes. - 140 p.

Adviser: Michael Rexach.

Thesis (Ph.D.)--Stanford University, 2005.

The nuclear pore complex (NPC) is a large proteinaceous entity that regulates all traffic between the nucleus and cytoplasm of eukaryotic cells. The NPC serves two major functions. First, it functions as a receptor for transport complexes to facilitate their diffusion either into or out of the nucleus. Second, the NPC forms a permeability barrier that excludes molecules larger than its passive diffusion limit of &sim;30--40 kDa. Approximately 30 proteins (nucleoporins, nups) present in multiple copies comprise the NPC. A subgroup of these proteins, termed FG nups, contain characteristic dipeptide repeats of phenylalanine-glycine. Carrier-mediated transport through the NPC is believed to involve stochastic interactions with these FG nups, however, precisely which FG nups are utilized and how the interaction is regulated is not fully understood. We first reconstituted the docking of complexes based on the transport receptor, Kap95, to NPCs in vitro using isolated nuclei as source of intact NPCs properly embedded in the nuclear envelope (Chapter II, Appendix A). We found that a subset of FG nups present at the cytoplasmic and central regions of the NPC contribute docking sites for Kap95 transport complexes, and that the docking of Kap95 is regulated by additional transport factors and temperature. Structural analysis of the FG nups revealed that they exist in a disordered state in purified form and in situ at NPCs (Chapter III). The structural disorder of FG nups led to a model in which FG nups present in the central cavity could fill it with a "meshwork" that would facilitate diffusion of bona fide transport complexes that could interact with it while excluding other macromolecules. Using a unique binding assay for low affinity interactions, we found that a subset of FG nups in the core of the NPC could transiently interact with each other via their FG motifs (Chapter IV). The transient interactions were reproduced in vivo, and shown to be important for maintaining the permeability barrier of NPCs. Together, our findings demonstrate that FG nups are critical for both of the major functions of the NPC, nuclear transport and maintenance of the permeability barrier.

ISBN: 9780542286490Subjects--Topical Terms:

226967
Biology, Cell.

The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes.
LDR:03219nmm _2200277 _450 001 170774
005 20061228142242.5
008 090528s2005 eng d
020 $a 9780542286490
035 $a 00242804
040 $a UnM $c UnM
100 0 $a Patel, Samir Sharad. $3 244804
245 1 4 $a The dual role of FG nucleoporins in nuclear import and formation of the permeability barrier at nuclear pore complexes.
300 $a 140 p.
500 $a Adviser: Michael Rexach.
500 $a Source: Dissertation Abstracts International, Volume: 66-08, Section: B, page: 4040.
502 $a Thesis (Ph.D.)--Stanford University, 2005.
520 # $a The nuclear pore complex (NPC) is a large proteinaceous entity that regulates all traffic between the nucleus and cytoplasm of eukaryotic cells. The NPC serves two major functions. First, it functions as a receptor for transport complexes to facilitate their diffusion either into or out of the nucleus. Second, the NPC forms a permeability barrier that excludes molecules larger than its passive diffusion limit of &sim;30--40 kDa. Approximately 30 proteins (nucleoporins, nups) present in multiple copies comprise the NPC. A subgroup of these proteins, termed FG nups, contain characteristic dipeptide repeats of phenylalanine-glycine. Carrier-mediated transport through the NPC is believed to involve stochastic interactions with these FG nups, however, precisely which FG nups are utilized and how the interaction is regulated is not fully understood. We first reconstituted the docking of complexes based on the transport receptor, Kap95, to NPCs in vitro using isolated nuclei as source of intact NPCs properly embedded in the nuclear envelope (Chapter II, Appendix A). We found that a subset of FG nups present at the cytoplasmic and central regions of the NPC contribute docking sites for Kap95 transport complexes, and that the docking of Kap95 is regulated by additional transport factors and temperature. Structural analysis of the FG nups revealed that they exist in a disordered state in purified form and in situ at NPCs (Chapter III). The structural disorder of FG nups led to a model in which FG nups present in the central cavity could fill it with a "meshwork" that would facilitate diffusion of bona fide transport complexes that could interact with it while excluding other macromolecules. Using a unique binding assay for low affinity interactions, we found that a subset of FG nups in the core of the NPC could transiently interact with each other via their FG motifs (Chapter IV). The transient interactions were reproduced in vivo, and shown to be important for maintaining the permeability barrier of NPCs. Together, our findings demonstrate that FG nups are critical for both of the major functions of the NPC, nuclear transport and maintenance of the permeability barrier.
590 $a School code: 0212.
650 # 0 $a Biology, Cell. $3 226967
650 # 0 $a Chemistry, Biochemistry. $3 226900
650 # 0 $a Biophysics, General. $3 226901
690 $a 0379
690 $a 0487
690 $a 0786
710 0 # $a Stanford University. $3 212607
773 0 # $g 66-08B. $t Dissertation Abstracts International
790 $a 0212
790 1 0 $a Rexach, Michael, $e advisor
791 $a Ph.D.
792 $a 2005
856 4 0 $u http://libsw.nuk.edu.tw:81/login?url=http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3186373 $z http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3186373