Patterns of homoeologous gene expression shown by RNA sequencing in hexaploid bread wheat.
BMC Genomics
; 15: 276, 2014 Apr 11.
Article
en En
| MEDLINE
| ID: mdl-24726045
ABSTRACT
BACKGROUND:
Bread wheat (Triticum aestivum) has a large, complex and hexaploid genome consisting of A, B and D homoeologous chromosome sets. Therefore each wheat gene potentially exists as a trio of A, B and D homoeoloci, each of which may contribute differentially to wheat phenotypes. We describe a novel approach combining wheat cytogenetic resources (chromosome substitution 'nullisomic-tetrasomic' lines) with next generation deep sequencing of gene transcripts (RNA-Seq), to directly and accurately identify homoeologue-specific single nucleotide variants and quantify the relative contribution of individual homoeoloci to gene expression.RESULTS:
We discover, based on a sample comprising ~5-10% of the total wheat gene content, that at least 45% of wheat genes are expressed from all three distinct homoeoloci. Most of these genes show strikingly biased expression patterns in which expression is dominated by a single homoeolocus. The remaining ~55% of wheat genes are expressed from either one or two homoeoloci only, through a combination of extensive transcriptional silencing and homoeolocus loss.CONCLUSIONS:
We conclude that wheat is tending towards functional diploidy, through a variety of mechanisms causing single homoeoloci to become the predominant source of gene transcripts. This discovery has profound consequences for wheat breeding and our understanding of wheat evolution.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Poliploidía
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Triticum
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Genoma de Planta
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Regulación de la Expresión Génica de las Plantas
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Cromosomas de las Plantas
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Transcriptoma
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
BMC Genomics
Asunto de la revista:
GENETICA
Año:
2014
Tipo del documento:
Article