Question 1

How does electroporation allow DNA to enter cells?

Accepted Answer

Electroporation uses an electrical current to disrupt the plasma membrane stability, creating temporary pores. This allows DNA to penetrate the membrane. Simultaneously, the electric field causes negatively charged DNA to migrate toward the positive electrode, driving the genetic material into cells on that side of the injection site.

Question 2

Why is in ovo electroporation valuable for developmental biology research?

Accepted Answer

In ovo electroporation allows researchers to deliver genetic material to specific tissues at precise developmental time points within the intact embryo. This localized, stage-specific delivery enables scientists to examine genetic mechanisms governing individual developmental events without disrupting the embryo's natural environment.

Question 3

What tools are essential for performing in ovo electroporation?

Accepted Answer

Key tools include capillary needles made from pulled glass pipets for injecting DNA, electrodes consisting of exposed wires connected to an electroporator, and a microinjector or mouth pipet for controlling fluid movement. The electroporator generates electrical pulses with adjustable duration, frequency, and voltage, often activated by a foot pedal.

Question 4

What preparation steps are needed before electroporating a chick embryo?

Accepted Answer

Eggs must be incubated at 37°C until reaching the desired developmental stage. A window is cut in the shell, and physiological salt solution is added to prevent drying. The tissue of interest is positioned under a microscope, and the capillary needle containing the injection solution is carefully pierced into the embryo to deliver the genetic construct.

Question 5

How can electroporation be used to study gene function in developing embryos?

Accepted Answer

Electroporation can deliver gene silencing constructs to block expression or plasmids containing protein-encoding genes to promote expression in specific cell populations. Scientists can also introduce DNA constructs encoding fluorescent proteins to visualize cells and structures during development, enabling live imaging of complex developmental processes.

Question 6

What happens after electroporation is complete?

Accepted Answer

After electroporation, electrodes are removed and wiped with 70% ethanol. Antibiotic-supplemented salt solution is added to prevent infection, and the shell window is sealed with tape. Eggs are returned to the incubator for continued development before phenotypic analysis or imaging to assess the effects of the genetic manipulation.

Question 7

When should researchers use ex ovo culture instead of in ovo electroporation?

Accepted Answer

For embryos older than Hamburger Hamilton stage 20, ex ovo culture provides improved tissue access compared to in ovo procedures. This video focuses on early embryos developing within the shell, but older chicks benefit from external culturing methods that allow better manipulation and visualization of developing tissues.

In ovo Electroporation of Chicken Embryos - Assessment Quiz