) Western blot detected the expression of p21, CDK1 and Bcl-2 in RA549 under 6 Gy treatment.

The Western blot technique was used to detect the expression of p21, CDK1, and Bcl-2 in RA549 cells under 6 Gy treatment. Here's a step-by-step breakdown of the process:

1. Sample Preparation: The RA549 cells were first treated with 6 Gy radiation. After treatment, the cells were harvested and lysed to extract the proteins.

2. Gel Electrophoresis: The extracted proteins were then separated based on their molecular weight using a technique called gel electrophoresis.

3. Transfer: The separated proteins were transferred from the gel onto a membrane, creating a 'blot'.

4. Blocking: The membrane was then blocked to prevent non-specific binding of the antibodies.

5. Primary Antibody Incubation: The membrane was incubated with primary antibodies that are specific to p21, CDK1, and Bcl-2. These antibodies bind to their respective proteins if they are present in the sample.

6. Secondary Antibody Incubation: After washing off the excess primary antibodies, the membrane was incubated with secondary antibodies. These antibodies recognize the primary antibodies and are usually conjugated with an enzyme that can produce a detectable signal.

7. Detection: The membrane was then treated with a substrate that reacts with the enzyme on the secondary antibodies, producing a signal that can be detected and visualized. The intensity of this signal is proportional to the amount of the target protein (p21, CDK1, Bcl-2) present in the sample.

8. Analysis: The signals were then analyzed to determine the expression levels of p21, CDK1, and Bcl-2 in the RA549 cells under 6 Gy treatment.