Just how complex is the Brassica S-receptor complex?
Of the plant self-incompatibility (SI) systems investigated to date, that possessed by members of the Brassicaceae is currently the best understood. Whilst the recent demonstrations of interactions between the male determinant (S-locus cysteine rich protein, SCR) and the female determinant (S-locus receptor kinase, SRK) indicate the minimal requirement for SI in Brassica, no consensus exists as to the nature of these molecules in vivo and the potential involvement of accessory molecules in establishing the active S-receptor complex. Variation between S haplotypes appears to be present in the molecular composition of the receptor complex, the regulation of downstream signalling and the requirement for accessory molecules. This review discusses what constitutes an active receptor complex and highlights potential differences between haplotypes. The role of accessory molecules, in particular SLG (S-locus glycoprotein) and low molecular weight pollen coat proteins (PCPs), in pollination are discussed, as is the link between SI and unilateral incompatibility (UI).
Kemp
Benjamin P
BP
Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, UK. bssjd@bath.ac.uk
Doughty
James
J
D029681:Arabidopsis Proteins; D001937:Brassica / Q000235:genetics* / Q000502:physiology; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D005298:Fertility / Q000235:genetics / Q000502:physiology; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011058:Pollen / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism
D029681:Arabidopsis Proteins; D015820:Cadherins; D006023:Glycoproteins; D010940:Plant Proteins; C401308:SCR protein, Brassica oleracea; C431526:SP11 protein, Brassica; C064156:self-incompatibility locus specific glycoprotein, Brassica; C076705:SLR1 protein, Brassica; D011494:Protein Kinases; C079832:S-receptor kinase; C090240:KAPP protein, Arabidopsis; D010749:Phosphoprotein Phosphatases