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Title: Sequence analysis of the Petunia inflata S ‐locus region containing 17 S‐Locus F‐Box genes and the S‐RNase gene involved in self‐incompatibility
SUMMARY

Self‐incompatibility inPetuniais controlled by the polymorphicS‐locus, which containsS‐RNaseencoding the pistil determinant and 16–20S‐locus F‐box(SLF) genes collectively encoding the pollen determinant. Here we sequenced and assembled approximately 3.1 Mb of theS2‐haplotype of theS‐locus inPetunia inflatausing bacterial artificial chromosome clones collectively containing all 17SLFgenes,SLFLike1, andS‐RNase. TwoSLFpseudogenes and 28 potential protein‐coding genes were identified, 20 of which were also found at theS‐loci of both theS6a‐haplotype ofP. inflataand theSN‐haplotype of self‐compatiblePetunia axillaris, but not in theS‐locus remnants of self‐compatible potato (Solanum tuberosum) and tomato (Solanum lycopersicum). Comparative analyses ofS‐locus sequences of these threeS‐haplotypes revealed potential genetic exchange in the flanking regions ofSLFgenes, resulting in highly similar flanking regions between different types ofSLFand between alleles of the same type ofSLFof differentS‐haplotypes. The high degree of sequence similarity in the flanking regions could often be explained by the presence of similar long terminal repeat retroelements, which were enriched at theS‐loci of all threeS‐haplotypes and in the flanking regions of allS‐locus genes examined. We also found evidence of the association of transposable elements withSLFpseudogenes. Based on the hypothesis thatSLFgenes were derived by retrotransposition, we identified 10F‐boxgenes as putativeSLFparent genes. Our results shed light on the importance of non‐coding sequences in the evolution of theS‐locus, and on possible evolutionary mechanisms of generation, proliferation, and deletion ofSLFgenes.

 
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Award ID(s):
1645557
NSF-PAR ID:
10455548
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
The Plant Journal
Volume:
104
Issue:
5
ISSN:
0960-7412
Page Range / eLocation ID:
p. 1348-1368
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  1. Summary

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