Does negative auto-regulation increase gene duplicability?
BACKGROUND
A prerequisite for a duplication to spread through and persist in a given population is retaining expression of both gene copies. Yet changing a gene's dosage is frequently detrimental to fitness. Consequently, dosage-sensitive genes are less likely to duplicate. However, in cases where the level of gene product is controlled, via negative feedback, by its own abundance, an increase in gene copy number can in principle be decoupled from an increase in protein while both copies remain expressed. Using data from the transcriptional networks of E. coli and S. cerevisiae, we test the hypothesis that genes under negative auto-regulation show enhanced duplicability.


RESULTS
Controlling for several known correlates of duplicability, we find no statistically significant support in either E. coli or S. cerevisiae that transcription factors under negative auto-regulation hold a duplicability advantage over transcription factors with no auto-regulation.


CONCLUSIONS
Based on the analysis of transcriptional networks in E. coli and S. cerevisiae, there is no evidence that negative auto-regulation has contributed, on a genome-wide scale, to the variability in gene family sizes in these species.
Warnecke
Tobias
T
Department of Biology & Biochemistry, University of Bath, UK. T.Warnecke@bath.ac.uk
Wang
Guang-Zhong
GZ
Lercher
Martin J
MJ
Hurst
Laurence D
LD
D004926:Escherichia coli / Q000235:genetics; D019143:Evolution, Molecular; D020440:Gene Duplication; D015964:Gene Expression Regulation, Bacterial; D015966:Gene Expression Regulation, Fungal; D053263:Gene Regulatory Networks; D016680:Genome, Bacterial; D016681:Genome, Fungal; D012441:Saccharomyces cerevisiae / Q000235:genetics; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics
D014157:Transcription Factors