BACKGROUND: Global transcript levels throughout the cell cycle have been characterized using microarrays in several species. Early analysis of these experiments focused on individual species. More recently, a number of studies have concluded that a surprisingly small number of genes conserved in two or more species are periodically transcribed in these species. Combining and comparing data from multiple species is challenging because of noise in expression data, the different synchronization and scoring methods used, and the need to determine an accurate set of homologs. RESULTS: To solve these problems, we developed and applied a new algorithm to analyze expression data from multiple species simultaneously. Unlike previous studies, we find that more than 20% of cycling genes in budding yeast have cycling homologs in fission yeast and 5% to 7% of cycling genes in each of four species have cycling homologs in all other species. These conserved cycling genes display much stronger cell cycle characteristics in several complementary high throughput datasets. Essentiality analysis for yeast and human genes confirms these findings. Motif analysis indicates conservation in the corresponding regulatory mechanisms. Gene Ontology analysis and analysis of the genes in the conserved sets sheds light on the evolution of specific subfunctions within the cell cycle. CONCLUSION: Our results indicate that the conservation in cyclic expression patterns is much greater than was previously thought. These genes are highly enriched for most cell cycle categories, and a large percentage of them are essential, supporting our claim that cross-species analysis can identify the core set of cycling genes.
BACKGROUND: Global transcript levels throughout the cell cycle have been characterized using microarrays in several species. Early analysis of these experiments focused on individual species. More recently, a number of studies have concluded that a surprisingly small number of genes conserved in two or more species are periodically transcribed in these species. Combining and comparing data from multiple species is challenging because of noise in expression data, the different synchronization and scoring methods used, and the need to determine an accurate set of homologs. RESULTS: To solve these problems, we developed and applied a new algorithm to analyze expression data from multiple species simultaneously. Unlike previous studies, we find that more than 20% of cycling genes in budding yeast have cycling homologs in fission yeast and 5% to 7% of cycling genes in each of four species have cycling homologs in all other species. These conserved cycling genes display much stronger cell cycle characteristics in several complementary high throughput datasets. Essentiality analysis for yeast and human genes confirms these findings. Motif analysis indicates conservation in the corresponding regulatory mechanisms. Gene Ontology analysis and analysis of the genes in the conserved sets sheds light on the evolution of specific subfunctions within the cell cycle. CONCLUSION: Our results indicate that the conservation in cyclic expression patterns is much greater than was previously thought. These genes are highly enriched for most cell cycle categories, and a large percentage of them are essential, supporting our claim that cross-species analysis can identify the core set of cycling genes.
Authors: Jean-François Rual; Kavitha Venkatesan; Tong Hao; Tomoko Hirozane-Kishikawa; Amélie Dricot; Ning Li; Gabriel F Berriz; Francis D Gibbons; Matija Dreze; Nono Ayivi-Guedehoussou; Niels Klitgord; Christophe Simon; Mike Boxem; Stuart Milstein; Jennifer Rosenberg; Debra S Goldberg; Lan V Zhang; Sharyl L Wong; Giovanni Franklin; Siming Li; Joanna S Albala; Janghoo Lim; Carlene Fraughton; Estelle Llamosas; Sebiha Cevik; Camille Bex; Philippe Lamesch; Robert S Sikorski; Jean Vandenhaute; Huda Y Zoghbi; Alex Smolyar; Stephanie Bosak; Reynaldo Sequerra; Lynn Doucette-Stamm; Michael E Cusick; David E Hill; Frederick P Roth; Marc Vidal Journal: Nature Date: 2005-09-28 Impact factor: 49.962
Authors: Christopher T Harbison; D Benjamin Gordon; Tong Ihn Lee; Nicola J Rinaldi; Kenzie D Macisaac; Timothy W Danford; Nancy M Hannett; Jean-Bosco Tagne; David B Reynolds; Jane Yoo; Ezra G Jennings; Julia Zeitlinger; Dmitry K Pokholok; Manolis Kellis; P Alex Rolfe; Ken T Takusagawa; Eric S Lander; David K Gifford; Ernest Fraenkel; Richard A Young Journal: Nature Date: 2004-09-02 Impact factor: 49.962
Authors: Natàlia Garcia-Reyero; Tanwir Habib; Mehdi Pirooznia; Kurt A Gust; Ping Gong; Chris Warner; Mitchell Wilbanks; Edward Perkins Journal: Ecotoxicology Date: 2011-03-29 Impact factor: 2.823
Authors: Benjamin D Landry; Claudine E Mapa; Heather E Arsenault; Kristin E Poti; Jennifer A Benanti Journal: EMBO J Date: 2014-04-08 Impact factor: 11.598