1999 Fiscal Year Final Research Report Summary
Analysis of carbohydrate recognition mechanism in fertilization
| Project/Area Number |
10680578
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Structural biochemistry
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| Research Institution | The University of Tokyo |
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Principal Investigator |
TAKASAKI Seiichi The University of Tokyo, Institute of Medical Science, Associate Professor, 医科学研究所, 助教授 (80112093)
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| Project Period (FY) |
1998 – 1999
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| Keywords | gamete / carbohydrate recognition system / sperm / egg / fertilization |
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| Research Abstract |
It has been suggested that multiple carbohydrate recognition systems are working in the gamete interaction. In this project, carbohydrate structures of eggs recognized by boar sperm and carbohydrate recognition molecules on sperm were investigated on the basis of oligosaccharide structures of porcine zona pellucida glycoproteins, and the following results were obtained.
1) Observation of sperm binding to fetuin-beads and their glycosidase digests showed that boar sperm recognize sialyl and non-sialyl N-acetyllactosamine structures.
2) The sperm also adhered to LeィイD1xィエD1 oligosaccharide probe-coupled avidin-Sepharose beads, but not to beads carrying sialyl LeィイD1xィエD1 and type 2H oligosaccharides and Fuc-GlcNA.
3) It was shown by the competition experiment that recognition of the LeィイD1xィエD1 structure by sperm is distinct from that of the sialyl and non-sialyl N-acetyllactosamine structures.
4) Dextran-based multivalent oligosaccharide polymers carrying either of sialyl and non-sialyl N-acetyllactosamine and LeィイD1xィエD1 structures, which were prepared by our recently developped method, inhibited sperm binding to eggs.
5) Cytochemical analysis using biotinylated multivalent oligosaccharide probes and fluorescent streptoavidin indicated that the heads of capacitated sperm are stained with either of the probes carrying sialyl and non-sialyl N-acetyllactosamine and LeィイD1xィエD1 structures, but those of acrosome-reacted sperm are not.
These results suggest that multiple interactions between several carbohydrate recognition molecules on sperm and their oligosaccharide ligands on eggs are involved in fertilization.
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