Final answer:
To check if a virus was generated after transfection, cytopathic effects can be observed under a microscope, radioisotopes such as 32P and 35S can trace viral components in the host, and techniques like agarose gel electrophoresis can be used to visualize viral DNA.
Step-by-step explanation:
Detection of a Virus After Transfection
To check if a virus has been generated after transfection, several methods can be employed. Observing cytopathic effects (CPEs) under a microscope can indicate viral infection, as these are distinct cell abnormalities caused by viruses. Additionally, experiments using radioisotopes, such as those with 32P-labeled or 35S-labeled viruses, provide insight into whether viral DNA or proteins have entered the host cells. The use of isotopes allows researchers to track the location of viral components; for example, 32P will be found in the pellet when it labels DNA, indicating that the viral genetic material is present in the host cells. 35S, however, will be found in the supernatant when it labels proteins, which may mean it is present in parts of the virus that did not enter the cell. In case the viral protein was tagged with an isotope and transferred to the host cell, the localization of the tagged protein can verify successful infection and transfection.
Moreover, if viral genes are present after infection, infected cells will lyse over time, revealing their impact on the host's cell survival and morphology. Another method that can be used to check the presence of viral components is agarose gel electrophoresis, which separates DNA fragments of different sizes, allowing visualization of the extracted viral DNA.