Linked Life Data

12788232

Source:http://linkedlifedata.com/resource/pubmed/id/12788232

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-6-5
pubmed:abstractText
It is an open question whether phenomena such as phenotypic robustness to mutation evolve as adaptations or are simply an inherent property of genetic systems. As a case study, we examine this question with regard to dominance in metabolic physiology. Traditionally the conclusion that has been derived from Metabolic Control Analysis has been that dominance is an inevitable property of multi-enzyme systems and hence does not require an evolutionary explanation. This view is based on a mathematical result commonly referred to as the flux summation theorem. However it is shown here that for mutations involving finite changes (of any magnitude) in enzyme concentration, the flux summation theorem can only hold in a very restricted set of conditions. Using both analytical and simulation results we show that for finite changes, the summation theorem is only valid in cases where the relationship between genotype and phenotype is linear and devoid of non-linearities in the form of epistasis. Such an absence of epistasis is unlikely in metabolic systems. As an example, we show that epistasis can arise in scenarios where we assume generic non-linearities such as those caused by enzyme saturation. In such cases dominance levels can be modified by mutations that affect saturation levels. The implication is that dominance is not a necessary property of metabolic systems and that it can be subject to evolutionary modification.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0025-5564
pubmed:author
pubmed:issnType
Print
pubmed:volume
184
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27-51
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Effects of epistasis on phenotypic robustness in metabolic pathways.
pubmed:affiliation
Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA. bagheri@santafe.edu
pubmed:publicationType
Journal Article