Journal article
How flowering plants discriminate between self and non-self pollen to prevent inbreeding
Proceedings of the National Academy of Sciences - PNAS, Vol.93(22), pp.12059-12065
10/29/1996
Handle:
https://hdl.handle.net/2376/108747
PMCID: PMC37941
PMID: 8901531
Abstract
Flowering plants have evolved various genetic mechanisms to circumvent the tendency for self-fertilization created by the close proximity of male and female reproductive organs in a bisexual flower. One such mechanism is gametophytic self-incompatibility, which allows the female reproductive organ, the pistil, to distinguish between self pollen and non-self pollen; self pollen is rejected, whereas non-self pollen is accepted for fertilization. The Solanaceae family has been used as a model to study the molecular and biochemical basis of self/non-self-recognition and self-rejection. Discrimination of self and non-self pollen by the pistil is controlled by a single polymorphic locus, the S locus. The protein products of S alleles in the pistil, S proteins, were initially identified based on their cosegregation with S alleles. S proteins have recently been shown to indeed control the ability of the pistil to recognize and reject self pollen. S proteins are also RNases, and the RNase activity has been shown to be essential for rejection of self pollen, suggesting that the biochemical mechanism of self-rejection involves the cytotoxic action of the RNase activity. S proteins contain various numbers of N-linked glycans, but the carbohydrate moiety has been shown not to be required for the function of S proteins, suggesting that the S allele specificity determinant of S proteins lies in the amino acid sequence. The male component in self-incompatibility interactions, the pollen S gene, has not yet been identified. The possible nature of the pollen S gene product and the possible mechanism by which allele-specific rejection of pollen is accomplished are discussed.
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Details
- Title
- How flowering plants discriminate between self and non-self pollen to prevent inbreeding
- Creators
- T H Kao - Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park 16802, USAA G McCubbin - Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park 16802, USA
- Publication Details
- Proceedings of the National Academy of Sciences - PNAS, Vol.93(22), pp.12059-12065
- Academic Unit
- Biological Sciences, School of
- Identifiers
- 99900547478201842
- Language
- English
- Resource Type
- Journal article