How to make a biological switch.
J Theor Biol
; 203(2): 117-33, 2000 Mar 21.
Article
in En
| MEDLINE
| ID: mdl-10704297
ABSTRACT
Some biological regulatory systems must "remember" a state for long periods of time. A simple type of system that can accomplish this task is one in which two regulatory elements negatively regulate one another. For example, two repressor proteins might control one another's synthesis. Qualitative reasoning suggests that such a system will have two stable states, one in which the first element is "on" and the second "off", and another in which these states are reversed. Quantitative analysis shows that the existence of two stable steady states depends on the details of the system. Among other things, the shapes of functions describing the effect of one regulatory element on the other must meet certain criteria in order for two steady states to exist. Many biologically reasonable functions do not meet these criteria. In particular, repression that is well described by a Michaelis-Menten-type equation cannot lead to a working switch. However, functions describing positive cooperativity of binding, non-additive effects of multiple operator sites, or depletion of free repressor can lead to working switches.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Gene Expression Regulation
/
Genes, Switch
/
Models, Genetic
Type of study:
Prognostic_studies
/
Qualitative_research
Limits:
Animals
Language:
En
Journal:
J Theor Biol
Year:
2000
Document type:
Article
Affiliation country:
Estados Unidos