Intracellular posttranslational protein targeting

Ben Abell

Protein
 localisation 
underpins 
cellular 
architecture 
and 
biochemical 
networks. 
Whilst 
we 
understand
 the
 steady 
state
 condition 
and 
many 
of 
the 
protein 
targeting 
processes, 
we 
lack 
a 
global
 model 
of
 protein
 segregation. 
In 
the
 simplest 
model, 
proteins
 possess
 a 
signal 
sequence
 that 
is 
bound 
by 
a
 targeting 
factor, 
which
 ensures
 delivery
 to 
a 
specific
 organelle. 
Although 
this 
may
 be 
specific 
and
 robust
 in 
some 
cases, 
it 
is 
possible
 for
 proteins
 to 
become 
mistargeted
 in
 a 
wide
 range
 of 
conditions.
 Furthermore,
 some
 proteins
 are
 targeted 
to 
multiple
 locations 
to 
facilitate
 their 
normal 
functions. 
Our 
hypothesis
 is 
that 
proteins
 are
 segregated
 by 
competitive 
binding
 of 
targeting
 factors, 
and
 by 
specific 
recognition 
at 
organellar
 receptors.
 The
 aim 
of 
this 
proposal
 is 
to 
devise a
 systematic 
framework 
for 
understanding 
how 
protein
 segregation 
occurs 
reliably
 and
 flexibly.

Proceedings of the 3rd Mathematics in the Plant Sciences study group