Abstract
The adhesion of pollen grains to the stigma is the first step of pollination in flowering plants. During this step, stigmas discriminate between pollen grains that can and cannot be permitted to effect fertilization. This selection is operated by various constituents of the cell walls of both partners. Several genes structurally related to the self-incompatibility system that prevents self-pollination in Brassica spp are known to target their products into the stigma cell wall. We proposed previously that one of these genes, the one encoding the S locus glycoprotein (SLG)-like receptor 1 (SLR1), which is coexpressed with that encoding SLG, may participate in pollen-stigma adhesion. Here, we exploit a biomechanical assay to measure the pollen adhesion force and show that it is reduced both by transgenic suppression of SLR1 expression and by pretreatment of wild-type stigmas with anti-SLR1 antibodies, anti-SLG antibodies, or pollen coat-protein extracts. Our results indicate a common adhesive function for the SLR1 and SLG proteins in the pollination process.
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- Delorme V., Giranton J. L., Hatzfeld Y., Friry A., Heizmann P., Ariza M. J., Dumas C., Gaude T., Cock J. M. Characterization of the S locus genes, SLG and SRK, of the Brassica S3 haplotype: identification of a membrane-localized protein encoded by the S locus receptor kinase gene. Plant J. 1995 Mar;7(3):429–440. doi: 10.1046/j.1365-313x.1995.7030429.x. [DOI] [PubMed] [Google Scholar]
- Doughty J., Dixon S., Hiscock S. J., Willis A. C., Parkin I. A., Dickinson H. G. PCP-A1, a defensin-like Brassica pollen coat protein that binds the S locus glycoprotein, is the product of gametophytic gene expression. Plant Cell. 1998 Aug;10(8):1333–1347. doi: 10.1105/tpc.10.8.1333. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Doughty J., Hedderson F., McCubbin A., Dickinson H. Interaction between a coating-borne peptide of the Brassica pollen grain and stigmatic S (self-incompatibility)-locus-specific glycoproteins. Proc Natl Acad Sci U S A. 1993 Jan 15;90(2):467–471. doi: 10.1073/pnas.90.2.467. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Edelman G. M. CAMs and Igs: cell adhesion and the evolutionary origins of immunity. Immunol Rev. 1987 Dec;100:11–45. doi: 10.1111/j.1600-065x.1987.tb00526.x. [DOI] [PubMed] [Google Scholar]
- Gaude T., Friry A., Heizmann P., Mariac C., Rougier M., Fobis I., Dumas C. Expression of a self-incompatibility gene in a self-compatible line of Brassica oleracea. Plant Cell. 1993 Jan;5(1):75–86. doi: 10.1105/tpc.5.1.75. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gaude T., Rougier M., Heizmann P., Ockendon D. J., Dumas C. Expression level of the SLG gene is not correlated with the self-incompatibility phenotype in the class II S haplotypes of Brassica oleracea. Plant Mol Biol. 1995 Mar;27(5):1003–1014. doi: 10.1007/BF00037027. [DOI] [PubMed] [Google Scholar]
- Goring D. R., Glavin T. L., Schafer U., Rothstein S. J. An S receptor kinase gene in self-compatible Brassica napus has a 1-bp deletion. Plant Cell. 1993 May;5(5):531–539. doi: 10.1105/tpc.5.5.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Griffiths G., Simons K., Warren G., Tokuyasu K. T. Immunoelectron microscopy using thin, frozen sections: application to studies of the intracellular transport of Semliki Forest virus spike glycoproteins. Methods Enzymol. 1983;96:466–485. doi: 10.1016/s0076-6879(83)96041-x. [DOI] [PubMed] [Google Scholar]
- Heldin C. H. Dimerization of cell surface receptors in signal transduction. Cell. 1995 Jan 27;80(2):213–223. doi: 10.1016/0092-8674(95)90404-2. [DOI] [PubMed] [Google Scholar]
- Hiscock S. J., Doughty J., Willis A. C., Dickinson H. G. A 7-kDa pollen coating-borne peptide from Brassica napus interacts with S-locus glycoprotein and S-locus-related glycoprotein. Planta. 1995;196(2):367–374. doi: 10.1007/BF00201397. [DOI] [PubMed] [Google Scholar]
- Kandasamy M. K., Paolillo D. J., Faraday C. D., Nasrallah J. B., Nasrallah M. E. The S-locus specific glycoproteins of Brassica accumulate in the cell wall of developing stigma papillae. Dev Biol. 1989 Aug;134(2):462–472. doi: 10.1016/0012-1606(89)90119-x. [DOI] [PubMed] [Google Scholar]
- Lalonde B. A., Nasrallah M. E., Dwyer K. G., Chen C. H., Barlow B., Nasrallah J. B. A highly conserved Brassica gene with homology to the S-locus-specific glycoprotein structural gene. Plant Cell. 1989 Feb;1(2):249–258. doi: 10.1105/tpc.1.2.249. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Luu D. T., Heizmann P., Dumas C. Pollen-Stigma Adhesion in Kale Is Not Dependent on the Self-(In)Compatibility Genotype. Plant Physiol. 1997 Nov;115(3):1221–1230. doi: 10.1104/pp.115.3.1221. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Preuss D., Lemieux B., Yen G., Davis R. W. A conditional sterile mutation eliminates surface components from Arabidopsis pollen and disrupts cell signaling during fertilization. Genes Dev. 1993 Jun;7(6):974–985. doi: 10.1101/gad.7.6.974. [DOI] [PubMed] [Google Scholar]
- Robert L. S., Allard S., Franklin T. M., Trick M. Sequence and expression of endogenous S-locus glycoprotein genes in self-compatible Brassica napus. Mol Gen Genet. 1994 Jan;242(2):209–216. doi: 10.1007/BF00391015. [DOI] [PubMed] [Google Scholar]
- Ross J. H., Murphy D. J. Characterization of anther-expressed genes encoding a major class of extracellular oleosin-like proteins in the pollen coat of Brassicaceae. Plant J. 1996 May;9(5):625–637. doi: 10.1046/j.1365-313x.1996.9050625.x. [DOI] [PubMed] [Google Scholar]
- Stanchev B. S., Doughty J., Scutt C. P., Dickinson H., Croy R. R. Cloning of PCP1, a member of a family of pollen coat protein (PCP) genes from Brassica oleracea encoding novel cysteine-rich proteins involved in pollen-stigma interactions. Plant J. 1996 Aug;10(2):303–313. doi: 10.1046/j.1365-313x.1996.10020303.x. [DOI] [PubMed] [Google Scholar]
- Stein J. C., Howlett B., Boyes D. C., Nasrallah M. E., Nasrallah J. B. Molecular cloning of a putative receptor protein kinase gene encoded at the self-incompatibility locus of Brassica oleracea. Proc Natl Acad Sci U S A. 1991 Oct 1;88(19):8816–8820. doi: 10.1073/pnas.88.19.8816. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tokuyasu K. T. Immunochemistry on ultrathin frozen sections. Histochem J. 1980 Jul;12(4):381–403. doi: 10.1007/BF01011956. [DOI] [PubMed] [Google Scholar]
- Trick M., Flavell R. B. A homozygous S genotype of Brassica oleracea expresses two S-like genes. Mol Gen Genet. 1989 Jul;218(1):112–117. doi: 10.1007/BF00330573. [DOI] [PubMed] [Google Scholar]
- Umbach A. L., Lalonde B. A., Kandasamy M. K., Nasrallah J. B., Nasrallah M. E. Immunodetection of protein glycoforms encoded by two independent genes of the self-incompatibility multigene family of brassica. Plant Physiol. 1990 Jun;93(2):739–747. doi: 10.1104/pp.93.2.739. [DOI] [PMC free article] [PubMed] [Google Scholar]
- da Silva Conceiço A., Marty-Mazars D., Bassham D. C., Sanderfoot A. A., Marty F., Raikhel N. V. The syntaxin homolog AtPEP12p resides on a late post-Golgi compartment in plants. Plant Cell. 1997 Apr;9(4):571–582. [PMC free article] [PubMed] [Google Scholar]