Recognition of a wide-range of S-RNases by S locus F-box like 2, a general-inhibitor candidate in the Prunus -specific S-RNase-based self-incompatibility system

摘要: Many species in the Rosaceae, Solanaceae, and Plantaginaceae exhibit S-RNase-based gametophytic self-incompatibility (GSI). This system comprises S-ribonucleases (S-RNases) as pistil S determinant a single or multiple F-box proteins pollen determinants. In Prunus, specificity is determined by haplotype-specific protein (SFB). The results of several studies suggested that SFB exerts cognate S-RNase cytotoxicity, hypothetical general inhibitor (GI) assumed to detoxify S-RNases non-specific manner unless it affected SFB. Although identity GI unknown, phylogenetic evolutionary analyses have indicated locus like 1-3 (or with low allelic sequence polymorphism 1-3; SLFL1-3), which are encoded region Prunus genome linked locus, good candidates. Here, we examined biochemical characteristics SLFL1-3 determine whether they appropriate characteristics. Pull-down assays quantitative expression avium mainly formed canonical SCF complex PavSSK1 PavCul1A. Binding PavS(1,3,4,6)-RNases showed PavSLFL1, PavSLFL2, PavSLFL3 bound PavS(3)-RNase, all PavS-RNases tested, none respectively. Together, these SLFL2 has be sweet cherry pollen, while SLFL1 may redundantly work S-RNases. We discuss possible roles Prunus-specific GSI mechanism.