title: A report on single exon genes (SEG) in eukaryotes.
abstract: Single exon genes (SEG) are archetypical of prokaryotes. Hence, their presence in intron-rich, multi-cellular eukaryotic genomes is perplexing. Consequently, a study on SEG origin and evolution is important. Towards this goal, we took the first initiative of identifying and counting SEG in nine completely sequenced eukaryotic organisms--four of which are unicellular (E. cuniculi, S. cerevisiae, S. pombe, P. falciparum) and five of which are multi-cellular (C. elegans, A. thaliana, D. melanogaster, M. musculus, H. sapiens). This exercise enabled us to compare their proportion in unicellular and multi-cellular genomes. The comparison suggests that the SEG fraction decreases with gene count (r = -0.80) and increases with gene density (r = 0.88) in these genomes. We also examined the distribution patterns of their protein lengths in different genomes.
authors.affiliation: Scool of Mechanical and Production Engineering, Nanyang Technological University, Singapore.
authors.forename: Meena Kishore
authors.initials: MK
authors.lastname: Sakharkar
authors.forename: Vincent Tak Kwong
authors.initials: VT
authors.lastname: Chow
authors.forename: Iti
authors.initials: I
authors.lastname: Chaturvedi
authors.forename: Venkatarajan Subramanian
authors.initials: VS
authors.lastname: Mathura
authors.forename: Paul
authors.initials: P
authors.lastname: Shapshak
authors.forename: Pandjassarame
authors.initials: P
authors.lastname: Kangueane
mesh_terms: D000818:Animals; D044822:Biodiversity; D030541:Databases, Genetic; D005057:Eukaryotic Cells / Q000378:metabolism; D019143:Evolution, Molecular; D005091:Exons; D016678:Genome; D023281:Genomics / Q000379:methods*; D006801:Humans; D008957:Models, Genetic; D013045:Species Specificity