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Title: Mutations in the predicted DNA polymerase subunit POLD3 result in more rapid flowering of Brachypodium distachyon
Summary

The timing of reproduction is a critical developmental decision in the life cycle of many plant species.

Fine mapping of a rapid‐flowering mutant was done using whole‐genome sequence data from bulked DNA from a segregating F2 mapping populations. The causative mutation maps to a gene orthologous with the third subunit of DNA polymerase δ (POLD3), a previously uncharacterized gene in plants. Expression analyses of POLD3 were conducted via real time qPCR to determine when and in what tissues the gene is expressed.

To better understand the molecular basis of the rapid‐flowering phenotype, transcriptomic analyses were conducted in the mutant vs wild‐type. Consistent with the rapid‐flowering mutant phenotype, a range of genes involved in floral induction and flower development are upregulated in the mutant.

Our results provide the first characterization of the developmental and gene expression phenotypes that result from a lesion inPOLD3in plants.

 
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Award ID(s):
1755224
PAR ID:
10456176
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
227
Issue:
6
ISSN:
0028-646X
Page Range / eLocation ID:
p. 1725-1735
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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