The Male Determinant of Self-Incompatibility in Brassica

• Published in: Science (American Association for the Advancement of Science) 1999-11, Vol.286 (5445), p.1697-1700
• Main Authors: Schopfer, Christel R., Nasrallah, Mikhail E., Nasrallah, June B.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Alleles; Amino Acid Sequence; Amino acids; Anthers; Biological and medical sciences; Biology; Brassica; Brassica - genetics; Brassica - physiology; Cysteine - chemistry; DNA; DNA probes; Females; Flowers & plants; Fundamental and applied biological sciences. Psychology; Gels; Genes, Plant; Genetic loci; Genetics and breeding of economic plants; Germination; Glycoproteins - genetics; Glycoproteins - metabolism; Haplotypes; Heterosis. Floral biology applications: apomixy, male sterility, incompatibility, varia; Homozygotes; Ligands; Males; Molecular Sequence Data; Nucleic Acid Hybridization; Plant breeding: fundamental aspects and methodology; Plant physiology and development; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Plant Proteins - physiology; Plant reproduction; Plant Structures - genetics; Plant Structures - physiology; Plants; Pollen; Pollen - genetics; Pollen - physiology; Polymorphism, Genetic; Protein Kinases - genetics; Protein Kinases - metabolism; Sequence Alignment; Sex (Botany); Sex in plants; Sexual reproduction; Transcripts (Written Records); Transformation, Genetic; Vegetative and sexual reproduction, floral biology, fructification
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.286.5445.1697

In the S locus-controlled self-incompatibility system of Brassica, recognition of serf-related pollen at the surface of stigma epidermal ceils leads to inhibition of pollen tube development. The female (stigmatic) determinant of this recognition reaction is a polymorphic transmembrane receptor protein kinase encoded at the S locus. Another highly polymorphic, anther-expressed gene, SCR, also encoded at the S locus, fulfills the requirements for the hypothesized pollen determinant. Loss-of-function and gain-of-function studies prove that the SCR gene product is necessary and sufficient for determining pollen selfincompatibility specificity, possibly by acting as a ligand for the stigmatic receptor.