The Role of a Pollen-Expressed Cullin1 Protein in Gametophytic Self-Incompatibility in Solanum

  title={The Role of a Pollen-Expressed Cullin1 Protein in Gametophytic Self-Incompatibility in Solanum},
  author={Wentao Li and Roger T. Chetelat},
  pages={439 - 442}
We previously isolated a pollen factor, ui6.1, which encodes a Cullin1 protein (CUL1) that functions in unilateral interspecific incompatibility (UI) in Solanum. Here we show that CUL1 is also required for pollen function in self-incompatibility (SI). We used RNA interference (RNAi) to reduce CUL1 expression in pollen of Solanum arcanum, a wild SI tomato relative. Hemizygous T0 plants showed little or no transmission of the transfer DNA (T-DNA) through pollen when crossed onto nontransgenic SI… 

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A farnesyl pyrophosphate synthase gene expressed in pollen functions in S-RNase-independent unilateral incompatibility.
The identified a major quantitative trait locus on chromosome 10 (ui10.1) which affects pollen-side UI responses in crosses between cultivated tomato, Solanum lycopersicum, and Solanu pennelliiLA0716, both of which are SC and lack S-RNase, the pistil determinant of S-specificity in Solanaceae.
Unilateral incompatibility gene ui1.1 encodes an S-locus F-box protein expressed in pollen of Solanum species
It is shown that ui1.1, a pollen UI factor in tomato, encodes an S-locus F-box protein that is homologous to an SI gene that in Petunia determines pollen specificity, demonstrating that pollen compatibility in UI is mediated by protein degradation through the ubiquitin–proteasome pathway, a mechanism related to that which controls pollen recognition in SI.
Mutations in two pollen self-incompatibility factors in geographically marginal populations of Solanum habrochaites impact mating system transitions and reproductive isolation.
Loss-of-function mutations in CUL1 and SLF-23 likely became fixed relatively late during SI to SC transitions, after loss of pistil SI function, and establish unilateral incompatibility with SI populations and strengthen reproductive isolation.
Duplicated pollen–pistil recognition loci control intraspecific unilateral incompatibility in Brassica rapa
Recognition between a novel pair of proteins, a pistil receptor SUI1 and a pollen ligand PUI1, triggers unilateral reproductive incompatibility between plants of two geographically distant self-incompatible Brassica rapa lines, even though crosses would be predicted to be compatible based on the S haplotypes of pollen and stigma.
Unilateral incompatibility is linked to reduced pollen expression of a farnesyl pyrophosphate synthase.
  • S. McCormick
  • Biology
    The Plant journal : for cell and molecular biology
  • 2018
Self-incompatibility (SI) is a breeding barrier that prevents self-fertilization in the cultivated tomato and in its wild relatives.
Identification of the self-incompatibility locus F-box protein-containing complex in Petunia inflata
All but Rbx1 of the complex may have evolved in SI, and all SLFs may be the F-box component of similar complexes.
Biochemical Recognition Specificity and Evolution of S-locus F-box Genes in Petunia Based Self-Incompatibility
An in-depth understanding of self-incompatibility, means discerning the biochemical basis for these SLF/non-self SRNase interactions, which is thought to work in a similar way to the SCFSLF complex.
SCFSLF-mediated cytosolic degradation of S-RNase is required for cross-pollen compatibility in S-RNase-based self-incompatibility in Petunia hybrida
It is demonstrated that SCFSLF-mediated non-self S-RNase degradation occurs in the cytosol of pollen tube through the ubiquitin/26S proteasome system serving as the major mechanism to neutralize S- RNase cytotoxicity during compatible pollination in P. hybrida.
HT proteins contribute to S‐RNase‐independent pollen rejection in Solanum
The results support the view that overall compatibility results from multiple pollen-pistil interactions with additive effects, and HT proteins are implicated in both S-RNase-dependent and S- RNase-independent pollen rejection.
Transcriptomic analysis links gene expression to unilateral pollen-pistil reproductive barriers
Gene expression analysis of reproductive tissues allowed us to better understand the molecular basis of interpopulation incompatibility at the level of pollen-pistil interactions and highlighted specific genes, including those in ROS signaling pathways that warrant further study in investigations of UI.


Fine Mapping of ui6.1, a Gametophytic Factor Controlling Pollen-Side Unilateral Incompatibility in Interspecific Solanum Hybrids
A high-resolution genetic map of this region delineated the location of the ui6.1 region and identified the underlying gene, which should elucidate the mechanism of interspecific pollen rejection and its relationship to self-incompatibility.
Identification of the pollen determinant of S-RNase-mediated self-incompatibility
It is concluded that PiSLF encodes the pollen self-incompatibility determinant, an S-locus F-box gene of Petunia inflata (Solanaceae), which is consistent with ‘competitive interaction’.
Genetic analysis of Nicotiana pollen-part mutants is consistent with the presence of an S-ribonuclease inhibitor at the S locus
The absence of pollen S deletions in this study and perhaps other studies suggests that pollen S might be required for pollen viability, possibly because its product acts as an S-RNase inhibitor.
A small asparagine-rich protein required for S-allele-specific pollen rejection in Nicotiana.
It is concluded that HT-protein is directly implicated in pollen rejection and contributes to the onset of S-allele-specific pollen rejection in the style.
Cultivated tomato has defects in both S-RNase and HT genes required for stylar function of self-incompatibility.
The results suggest that the breakdown of self-incompatibility in cultivated tomato is associated with loss-of-function mutations in both S-RNase and HT genes.
The Skp1-like protein SSK1 is required for cross-pollen compatibility in S-RNase-based self-incompatibility.
Results provide an example that a specific Skp1-like protein other than the known conserved ones can be recruited into a canonical SCF complex as an adaptor, and suggest that the pollen S determinant contributes to inhibiting rather than protecting the S-RNase activity, at least in solanaceous plants.
Collaborative Non-Self Recognition System in S-RNase–Based Self-Incompatibility
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A Pollen Factor Linking Inter- and Intraspecific Pollen Rejection in Tomato
C cultivated tomato may have lost the ability to pollinate other species within the same family, owing to the loss of this protein, and similar biochemical mechanisms underlie the rejection of both “self” and interspecific pollen are observed.
The stylar 120 kDa glycoprotein is required for S-specific pollen rejection in Nicotiana.
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Style self-incompatibility gene products of Nicotlana alata are ribonucleases
It is reported here that glycoproteins corresponding to the S1, S2, S3, S6 and S7 alleles isolated from style extracts of N. alata6 are ribonucleases, which implicate ribonuclease activity in the mechanism of gametophytic self-incompatibility.