TY - JOUR
T1 - Modeling of the Genetic Switch of Bacteriophage TP901-1
T2 - A Heteromer of CI and MOR Ensures Robust Bistability
AU - Nakanishi, Hiizu
AU - Pedersen, Margit
AU - Alsing, Anne K.
AU - Sneppen, Kim
N1 - Funding Information:
This work was supported by the Danish National Research Foundation through the Center for Models of Life.
PY - 2009/11/20
Y1 - 2009/11/20
N2 - The lytic-lysogenic switch of the temperate lactococcal phage TP901-1 is fundamentally different from that of phage lambda. In phage TP901-1, the lytic promoter PL is repressed by CI, whereas repression of the lysogenic promoter PR requires the presence of both of the antagonistic regulator proteins, MOR and CI. We model the central part of the switch and compare the two cases for PR repression: the one where the two regulators interact only on the DNA and the other where the two regulators form a heteromer complex in the cytoplasm prior to DNA binding. The models are analyzed for bistability, and the predicted promoter repression folds are compared to experimental data. We conclude that the experimental data are best reproduced the latter case, where a heteromer complex forms in solution. We further find that CI sequestration by the formation of MOR:CI complexes in cytoplasm makes the genetic switch robust.
AB - The lytic-lysogenic switch of the temperate lactococcal phage TP901-1 is fundamentally different from that of phage lambda. In phage TP901-1, the lytic promoter PL is repressed by CI, whereas repression of the lysogenic promoter PR requires the presence of both of the antagonistic regulator proteins, MOR and CI. We model the central part of the switch and compare the two cases for PR repression: the one where the two regulators interact only on the DNA and the other where the two regulators form a heteromer complex in the cytoplasm prior to DNA binding. The models are analyzed for bistability, and the predicted promoter repression folds are compared to experimental data. We conclude that the experimental data are best reproduced the latter case, where a heteromer complex forms in solution. We further find that CI sequestration by the formation of MOR:CI complexes in cytoplasm makes the genetic switch robust.
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U2 - 10.1016/j.jmb.2009.08.075
DO - 10.1016/j.jmb.2009.08.075
M3 - Article
C2 - 19747486
AN - SCOPUS:70350160788
SN - 0022-2836
VL - 394
SP - 15
EP - 28
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 1
ER -