Production of new transgenic Hydra via embryo microinjection
The introduction of foreign DNA (transgenes) into the genome of Hydra enables researchers to study gene expression and protein function in living polyps. Specialized transgenic facilities provide the means to generate such modified organisms under controlled laboratory conditions.
These facilities handle all essential steps required to produce transgenic Hydra, including preparing the setup, harvesting embryos, and performing DNA microinjection. Researchers are responsible for providing the purified DNA construct. Typically, a minimum of 20 viable embryos are microinjected per experiment. Once founder polyps carrying the transgene are identified, the facility can transfer the animals to the researcher. Routine mass culturing of transgenic lines, however, is not provided and remains the responsibility of the investigator.
The production of transgenic Hydra polyps involves several key steps:
- Construction of the transgenic vector: This includes incorporating a suitable promoter, the genomic DNA or clone of interest (with any necessary intron fragments), and polyadenylation sequences.
- Purification of the transgene: The DNA must be highly purified to ensure successful microinjection. Any contaminants or particulate matter can clog the injection needle or interfere with the integration of the DNA into the Hydra genome. It is recommended to isolate the DNA fragment using a reliable purification kit, such as the Qiagen Midi Prep Kit, and resuspend it in water.
- Microinjection into fertilized embryos: The purified transgene is introduced into fertilized Hydra eggs, allowing the DNA to integrate randomly into the genome and generate transgenic polyps.
Steps 1 and 2 are the responsibility of the investigator, while microinjection and subsequent embryo handling are performed at the transgenic facility.
Getting Started:
To begin producing transgenic Hydra, start by preparing your DNA construct carefully, ensuring it is pure and ready for injection. Once the DNA is ready, the embryos can be collected and the microinjection process can begin. Following these initial steps sets the foundation for creating transgenic polyps and observing gene function in living organisms.