Mosaic haploid-diploid embryos and polyspermy in the tellinid bivalve Macoma balthica
We investigated meiosis, fertilization, and early development in eggs of the tellinid bivalve Macoma balthica (L.), which has external fertilization. Meiosis is standard but polyspermy is found to be very common. In all eight crosses examined, mosaic embryos consisting of a mixture of diploid (2n =...
Main Authors: | , |
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Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2002
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Subjects: | |
Online Access: | https://hdl.handle.net/11370/c92a49a5-6d45-450c-b1e2-62baa5c549ab https://research.rug.nl/en/publications/c92a49a5-6d45-450c-b1e2-62baa5c549ab |
Summary: | We investigated meiosis, fertilization, and early development in eggs of the tellinid bivalve Macoma balthica (L.), which has external fertilization. Meiosis is standard but polyspermy is found to be very common. In all eight crosses examined, mosaic embryos consisting of a mixture of diploid (2n = 38) and haploid cells occur at a frequency ranging from 2.7 to 29.1%. The earliest mosaic found is in the two-cell stage. We propose that an androgenic haploid cell lineage can originate from one supernumerary sperm that decondenses into a functional haploid nucleus, starts mitosis, and is incorporated in the developing embryo. |
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