Transovarial inheritance of endosymbiotic bacteria in clams inhabiting deep-sea hydrothermal vents and cold seeps
Autor: | S J Giovannoni, S C Cary |
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Rok vydání: | 1993 |
Předmět: |
DNA
Bacterial animal structures Bacterial Physiological Phenomena Vesicomyidae Symbiosis RNA Ribosomal 16S Sequence Homology Nucleic Acid Animals Mollusca In Situ Hybridization Genetics Multidisciplinary biology Bacteria Base Sequence Host (biology) fungi Ovary Ribosomal RNA biochemical phenomena metabolism and nutrition biology.organism_classification Bivalvia Calyptogena magnifica Genes Bacterial bacteria Female Oligonucleotide Probes Polymorphism Restriction Fragment Length Research Article |
Zdroj: | Proceedings of the National Academy of Sciences of the United States of America. 90(12) |
ISSN: | 0027-8424 |
Popis: | Vesicomyid clams are conspicuous fauna at many deep-sea hydrothermal-vent and cold-seep habitats. All species examined have specialized gill tissue harboring endosymbiotic bacteria, which are thought to provide the hosts' sole nutritional support. In these species mechanisms of symbiont inheritance are likely to be key elements of dispersal strategies. These mechanisms have remained unresolved because the early life stages are not available for developmental studies. A specific 16S rRNA-directed oligodeoxynucleotide probe (CG1255R) for the vesocomyid endosymbionts was used in a combination of sensitive hybridization techniques to detect and localize the endosymbionts in host germ tissues. Symbiont-specific polymerase chain reaction amplifications, comparative gene sequencing, and restriction fragment length polymorphisms were used to detect and confirm the presence of symbiont target in tissue nucleic acid extracts. Nonradioactive in situ hybridizations were used to resolve the position of the bacterial endosymbionts in host cells. Symbiont 16S rRNA genes were consistently amplified from the ovarial tissue of three species of vesicomyid clams: Calyptogena magnifica, C. phaseoliformis, and C. pacifica. The nucleotide sequences of the genes amplified from ovaries were identical to those from the respective host symbionts. In situ hybridizations to CG1255R labeled with digoxigenin-11-dUTP were performed on ovarial tissue from each of the vesicomyid clams. Detection of hybrids localized the symbionts to follicle cells surrounding the primary oocytes. These results suggest that vesicomyid clams assure successful, host-specific inoculation of all progeny by using a transovarial mechanism of symbiont transmission. |
Databáze: | OpenAIRE |
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