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Title: Investigation of regulatory divergence between homoeologs in the recently formed allopolyploids, Tragopogon mirus and T. miscellus (Asteraceae)
SUMMARY

Polyploidy is an important evolutionary process throughout eukaryotes, particularly in flowering plants. Duplicated gene pairs (homoeologs) in allopolyploids provide additional genetic resources for changes in molecular, biochemical, and physiological mechanisms that result in evolutionary novelty. Therefore, understanding how divergent genomes and their regulatory networks reconcile is vital for unraveling the role of polyploidy in plant evolution. Here, we compared the leaf transcriptomes of recently formed natural allotetraploids (Tragopogon mirusandT. miscellus) and their diploid parents (T. porrifoliusXT. dubiusandT. pratensisXT. dubius, respectively). Analysis of 35 400 expressed loci showed a significantly higher level of transcriptomic additivity compared to old polyploids; only 22% were non‐additively expressed in the polyploids, with 5.9% exhibiting transgressive expression (lower or higher expression in the polyploids than in the diploid parents). Among approximately 7400 common orthologous regions (COREs), most loci in both allopolyploids exhibited expression patterns that were vertically inherited from their diploid parents. However, 18% and 20.3% of the loci showed novel expression bias patterns inT. mirusandT. miscellus, respectively. The expression changes of 1500 COREs were explained bycis‐regulatory divergence (the condition in which the two parental subgenomes do not interact) between the diploid parents, whereas only about 423 and 461 of the gene expression changes representtrans‐effects (the two parental subgenomes interact) inT. mirusandT. miscellus, respectively. The low degree of both non‐additivity andtrans‐effects on gene expression may present the ongoing evolutionary processes of the newly formedTragopogonpolyploids (~80–90 years).

 
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NSF-PAR ID:
10476595
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
ISSN:
0960-7412
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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