Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Mathematical model of alternative mechanism of telomere length
  maintenance   Biopolymer length regulation is a complex process that involves a large
number of subprocesses acting simultaneously across multiple spatial and
temporal scales. An illustrative example important for genomic stability is the
length regulation of telomeres---nucleo-protein structures at the ends of
linear chromosomes. Maintenance of telomeres is often facilitated by the enzyme
telomerase but, particularly in telomerase-free systems, the maintenance of
chromosomal termini depends on alternative lengthening of telomeres (ALT)
mechanisms mediated by recombination. Various linear and circular DNA
structures were identified to participate in ALT, however, dynamics of the
whole process is still poorly understood. We propose a chemical kinetics model
of ALT with kinetic rates systematically derived from the biophysics of DNA
diffusion and looping. The reaction system is reduced to a
coagulation-fragmentation system by quasi-steady state approximation. The
detailed treatment of kinetic rates yields explicit formulae for expected size
distributions of telomeres that demonstrate the key role played by the
J-factor, a quantitative measure of bending of polymers. The results are in
agreement with experimental data and point out interesting phenomena: an
appearance of very long telomeric circles if the total telomere density exceeds
a critical value (excess mass) and a nonlinear response of the telomere size
distributions to the amount of telomeric DNA in the system. The results can be
of general importance for understanding dynamics of telomeres in
telomerase-independent systems as this mode of telomere maintenance is similar
to the situation in tumor cells lacking telomerase activity. Furthermore, due
to its universality, the model may also serve as a prototype of an interaction
between linear and circular DNA structures in various settings.

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The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
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The categories of this paper are: q-fin
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The categories of this paper are: math
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess