A disulfide bond A-like oxidoreductase is a strong candidate gene for self-incompatibility in apricot (Prunus armeniaca) pollen

作者：Vicente Munoz Sanz Juan; Zuriaga Elena; Badenes Maria L; Romero Carlos^*

来源：Journal of Experimental Botany, 2017, 68(18): 5069-5078.

DOI：10.1093/jxb/erx336

• DsbA oxidoreductase
• gametophytic self-incompatibility
• M-locus
• modifier
• pollen-part mutation
• Prunus

S-RNase based gametophytic self-incompatibility (SI) is a widespread prezygotic reproductive barrier in flowering plants. In the Solanaceae, Plantaginaceae and Rosaceae gametophytic SI is controlled by the pistil-specific S-RNases and the pollen S-locus F-box proteins but non-S-specific factors, namely modifiers, are also required. In apricot, Prunus armeniaca (Rosaceae), we previously mapped two pollen-part mutations that confer self-compatibility in cultivars Canino and Katy at the distal end of chromosome 3 (M-locus) unlinked to the S-locus. Here, we used high-resolution mapping to identify the M-locus with an similar to 134 kb segment containing ParM-1-16 genes. Gene expression analysis identified four genes preferentially expressed in anthers as modifier gene candidates, ParM-6, -7, -9 and -14. Variant calling of WGS Illumina data from Canino, Katy, and 10 self-incompatible cultivars detected a 358 bp miniature inverted-repeat transposable element (MITE) insertion in ParM-7 shared only by self-compatible apricots, supporting ParM-7 as strong candidate gene required for SI. ParM-7 encodes a disulfide bond A-like oxidoreductase protein, which we named ParMDO. The MITE insertion truncates the ParMDO ORF and produces a loss of SI function, suggesting that pollen rejection in Prunus is dependent on redox regulation. Based on phylogentic analyses we also suggest that ParMDO may have originated from a tandem duplication followed by subfunctionalization and pollenspecific expression.

• 出版日期2017-8-15