Genetics. Published Articles Ahead of Print: December 1, 2005, Copyright © 2005
doi:10.1534/genetics.105.049890


A more recent version of this article appeared on February 1, 2006.

NOTE

Transcriptional reprogramming and backup between duplicate genes: is it a genome-wide phenomenon?

Xionglei He 1 and Jianzhi Zhang 1*

1 University of Michigan

* To whom correspondence should be addressed. E-mail: jianzhi{at}umich.edu.

Submitted on August 22, 2005
Revised on November 2, 2005
Accepted on 7 November 2005


Abstract

Deleting a duplicate gene often results in a less severe phenotype than deleting a singleton gene, a phenomenon commonly attributed to functional compensation among duplicates. However, duplicate genes rapidly diverge in expression pattern after duplication, making functional compensation less probable for ancient duplicates. Case studies suggested that a gene may provide compensation by altering its expression upon removal of its duplicate copy. Based on this observation and a genomic analysis, it was recently proposed that transcriptional reprogramming and backup among duplicates is a genome-wide phenomenon in the yeast Saccharomyces cerevisiae. Here we reanalyze the yeast data and show that the high dispensability of duplicate genes with low expression similarity is a consequence of expression similarity and gene dispensability each being correlated with a third factor, the number of protein interactions per gene. There is little evidence supporting widespread functional compensation of divergently expressed duplicate genes by transcriptional reprogramming.

Key Words: duplicate genes, functional compensation, protein complex, protein-protein interaction, transcriptional reprogramming