Sex-Specific Expression of Alternative Transcripts in Drosophila

Authors

Lauren McIntyre, University of Florida, Gainesville, FL
Lisa Bono, Purdue University, West Lafayette, IN
Anne Genissel, University of California, Davis, California
Rick Westerman, Purdue University, West Lafayette, IN
Damion Junk, Purdue University, West Lafayette, IN
Marina Telonis-Scott, University of Florida, Gainesville, FL
Lawrence G. Harshman, University of Nebraska - LincolnFollow
Marta Wayne, University of Florida, Gainesville, FL
Artyom Kopp, Purdue UniversityFollow
Sergey V. Nuzhdin, University of California, Davis,

Document Type

Article

Date of this Version

2006

Comments

Published in Genome Biology 2006, 7:R79 (doi:10.1186/gb-2006-7-8-r79). Copyright © 2006 McIntyre et al.; licensee BioMed Central Ltd. Used by permission.

Abstract

Background: Many genes produce multiple transcripts due to alternative splicing or utilization of alternative transcription initiation/termination sites. This 'transcriptome expansion' is thought to increase phenotypic complexity by allowing a single locus to produce several functionally distinct proteins. However, sex, genetic and developmental variation in the representation of alternative transcripts has never been examined systematically. Here, we describe a genome-wide analysis of sex-specific expression of alternative transcripts in Drosophila melanogaster.

Results: We compared transcript profiles in males and females from eight Drosophila lines (OregonR and 2b, and 6 RIL) using a newly designed 60-mer oligonucleotide microarray that allows us to distinguish a large proportion of alternative transcripts. The new microarray incorporates 7,207 oligonucleotides, satisfying stringent binding and specificity criteria that target both the common and the unique regions of 2,768 multi-transcript genes, as well as 12,912 oligonucleotides that target genes with a single known transcript. We estimate that up to 22% of genes that produce multiple transcripts show a sex-specific bias in the representation of alternative transcripts. Sexual dimorphism in overall transcript abundance was evident for 53% of genes. The X chromosome contains a significantly higher proportion of genes with female-biased transcription than the autosomes. However, genes on the X chromosome are no more likely to have a sexual bias in alternative transcript representation than autosomal genes.

Conclusion: Widespread sex-specific expression of alternative transcripts in Drosophila suggests that a new level of sexual dimorphism at the molecular level exists.