title: A pollen factor linking inter- and intraspecific pollen rejection in tomato.
abstract: Self-incompatibility (SI)--intraspecific pollen recognition systems that allow plants to avoid inbreeding--in the Solanaceae (the nightshade family) is controlled by a polymorphic S locus where "self" pollen is rejected on pistils with matching S alleles. In contrast, unilateral interspecific incompatibility (UI) prevents hybridization between related species, most commonly when the pollen donor is self-compatible (SC) and the recipient is SI. We observed that in Solanum, a pollen-expressed Cullin1 gene with high similarity to Petunia SI factors interacts genetically with a gene at or near the S locus to control UI. Cultivated tomato and related red- or orange-fruited species (all SC) exhibit the same loss-of-function mutation in this gene, whereas the green-fruited species (mostly SI) contain a functional allele; hence, similar biochemical mechanisms underlie the rejection of both "self" and interspecific pollen.
authors.affiliation: Department of Plant Sciences, University of California, Davis, CA 95616, USA.
authors.forename: Wentao
authors.initials: W
authors.lastname: Li
authors.forename: Roger T
authors.initials: RT
authors.lastname: Chetelat
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D003433:Crosses, Genetic; D044842:Cullin Proteins / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000502:physiology; D017343:Genes, Plant; D006824:Hybridization, Genetic; D007438:Introns; D018551:Solanum lycopersicum / Q000235:genetics* / Q000502:physiology*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified; D011058:Pollen / Q000235:genetics* / Q000502:physiology; D054817:Pollination; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D012260:Ribonucleases / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D032322:Solanum / Q000235:genetics* / Q000502:physiology
chemical_list: C100318:Cullin 1; D044842:Cullin Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D012260:Ribonucleases