Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multistationarity in sequential distributed multisite phosphorylation
  networks   Multisite phosphorylation networks are encountered in many intracellular
processes like signal transduction, cell-cycle control or nuclear signal
integration. In this contribution networks describing the phosphorylation and
dephosphorylation of a protein at $n$ sites in a sequential distributive
mechanism are considered. Multistationarity (i.e.\ the existence of at least
two positive steady state solutions of the associated polynomial dynamical
system) has been analyzed and established in several contributions. It is, for
example, known that there exist values for he rate constants where
multistationarity occurs. However, nothing else is known about these rate
constants.
  Here we present a sign condition that is necessary and sufficient for
multistationarity in $n$-site sequential, distributive phosphorylation. We
express this sign condition in terms of linear systems and show that solutions
of these systems define rate constants where multistationarity is possible. We
then present, for $n\geq 2$, a collection of {\em feasible} linear systems and
hence give a new and independent proof that multistationarity is possible for
$n\geq 2$. Moreover, our results allow to explicitly obtain values for the rate
constants where multistationarity is possible. Hence we believe that, for the
first time, a systematic exploration of the region in parameter space where
multistationarity occurs has become possible.One consequence of our work is
that, for any pair of steady states, the ratio of the steady state
concentrations of kinase-substrate complexes equals that of
phosphatase-substrate complexes.

19
The categories of this paper are: eess
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys