Sor$ngwithDisorderatNuclearPores - - PowerPoint PPT Presentation

Sor$ng

with

Disorder

at

Nuclear

Pores


Rexach
Lab






MCD
Biology




UC
Santa
Cruz


Nuclear

Export
 ribosome

subunits

 mRNA
 tRNA
 snRNA
 rRNA
 viral
RNP’s
 Nuclear

Import
 ribosomal

proteins

 transcrip$on

factors
 replica$on

factors
 nucleolar
proteins
 snRNA
 rRNA
 viral

genomes


Thousands
of
proteins
and
RNP’s
must
cross
the
nuclear
envelope
every
second


Nucleocytoplasmic

traffic

across

the

nuclear

envelope


The
nuclear
envelope
is
a
barrier


2


Chroma$n
 Nuclear
envelope


GTP


NES
‐
 NES
‐


Ran


expor$n
 expor$n


Sorts
based
on
size,
 hydrophobicity
&
charge
 
 Allows

facilitated

transport

via
 karyopherins

and

signals


impor$n
 ‐NLS


GTP
 GTP


impor$n
 ‐NLS
 ‐NLS


Ran


>30
kDa
 >3
nm


<
30
kDa
 <
3
nm


Nuclear

Pores

Are

Gated

by

a

Molecular

Sortase:

the
Nuclear
Pore
Complex


3


What
is
the
structure
of
the
sortase?


Nucleocytoplasmic

transport

machinery

in

S.
cerevisiae


FG
Nups
 Nup1
 Nup2
 Nup42
 Nup49
 Nup53
 Nup57
 Nup59
 Nup60
 Nup100
 Nup116
 nNup145
 Nup159
 Nsp1
 Non
FG
Nups
 Nup82
 Nup84
 Nup85
 Nup120
 Nup133
 cNup145
 Nup157
 Nup170
 Nup188
 Nup192
 Sec13
 Seh1
 Cdc31
 Nic96
 POMs
 Pom34
 Pom152
 Ndc1
 Impor$ns
 Kap95•Kap60
 Kap104
 Kap121
 Kap123
 Mtr10
 Nmd5
 Sxm1
 Pdr6
 Kap114
 N`2
 
 Transpor$ns
 Msn5
 Expor$ns
 Crm1
 Cse1
 Kap120
 Los1
 Mex67•Mtr2


Nuclear

Pore

Complex
 Nucleoporins
 Karyopherins


Ran
GTPase
and
effectors


What
is
the
structure
of
FG
nups?


4


4%







1%





95%
 13%






7%





80%
 7%






3%





90%
 4%







1%





95%
 6%






4%






90%
 2%






3%





95%
 50%





15%



35%
 alpha
 helix
 beta
 sheet
 random
 coil


Structural

analysis

of

FG

domains

of

Nups


500
 1,000
 0
 amino
acids


Nup2
 Nup159
 Nup57
 Nup85
 Nup1
 Nsp1


N
 C


Nup100
 FG
Nups
 non
FG
Nup


5


The

FG
domains

of

nucleoporins

are

intrinsically‐disordered
 and

form

a
meshwork
of
unfolded
polypep$des


~150
FG
Nups


Advantage
of
having
unfolded
proteins
in
the
NPC
conduit?
 
 Func$onal

>
can
bind
many
proteins
simultaneously,
karyopherins
 












>
have
fast
molecular
on/off
rates
to
“facilitate”
rapid
diffusion
 
 Structural


>
form
a
porous
filamentous
meshwork
that
restricts
free
diffusion
 












>
form
flexible
meshwork
that
accommodates
par$cles
of
all
shapes/sizes


6


Collaborators:
 
 Modeling:
M.
Colvin
&
Josh
Phillips
(UC
Merced),
 
 
E.
Lau
(LLNL)

 
 Spectroscopy:
K.
Krishnan
(UC
Davis)
 
 Polymer
Physics:
A.
Gopinathan
(UC
Merced)
 
 Protein
Structure:
V.
Uversky
(IU)
 
 Single
Molecules:
P.
Hinterdorfer
(Austria)


Rexach
Lab






MCD
Biology




UC
Santa
Cruz


Jus$n
Yamada
 Gisela
Colón
 Alison
Calestagne‐Morelli
 Hans
Huang