Genome-scale transcriptional analyses of first-generation interspecific sunflower hybrids reveals broad regulatory compatibility

BMC Genomics

Research Article

Loren H Rieseberg¹  Heather C Rowe¹ 

[1] Botany Department, University of British Columbia, V6T 1Z4, Vancouver, BC, Canada;

关键词: Hybridization;    Helianthus;    Introgression;    Gene flow;    Allelic bias;    Speciation;   

DOI  :  10.1186/1471-2164-14-342

 received in 2012-12-04, accepted in 2013-04-15,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundInterspecific hybridization creates individuals harboring diverged genomes. The interaction of these genomes can generate successful evolutionary novelty or disadvantageous genomic conflict. Annual sunflowers Helianthus annuus and H. petiolaris have a rich history of hybridization in natural populations. Although first-generation hybrids generally have low fertility, hybrid swarms that include later generation and fully fertile backcross plants have been identified, as well as at least three independently-originated stable hybrid taxa. We examine patterns of transcript accumulation in the earliest stages of hybridization of these species via analyses of transcriptome sequences from laboratory-derived F1 offspring of an inbred H. annuus cultivar and a wild H. petiolaris accession.ResultsWhile nearly 14% of the reference transcriptome showed significant accumulation differences between parental accessions, total F1 transcript levels showed little evidence of dominance, as midparent transcript levels were highly predictive of transcript accumulation in F1 plants. Allelic bias in F1 transcript accumulation was detected in 20% of transcripts containing sufficient polymorphism to distinguish parental alleles; however the magnitude of these biases were generally smaller than differences among parental accessions.ConclusionsWhile analyses of allelic bias suggest that cis regulatory differences between H. annuus and H. petiolaris are common, their effect on transcript levels may be more subtle than trans-acting regulatory differences. Overall, these analyses found little evidence of regulatory incompatibility or dominance interactions between parental genomes within F1 hybrid individuals, although it is unclear whether this is a legacy or an enabler of introgression between species.

【 授权许可】

CC BY   
© Rowe and Rieseberg; licensee BioMed Central Ltd. 2013