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

The statement you provided seems to be a result from a scientific experiment, not a question. However, I can explain what it means.

Western blot is a widely used analytical technique used in molecular biology, biochemistry, and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. In this case, it was used to detect the expression of p21, CDK1, and Bcl-2 in RA549 cells under a treatment of 6 Gy (a unit of radiation dose).

1. p21 is a protein that in humans is encoded by the CDKN1A gene. It is a potent cyclin-dependent kinase inhibitor (CKI). The p21 (WAF1) protein binds to and inhibits the activity of cyclin-CDK2 or -CDK4 complexes, and thus functions as a regulator of cell cycle progression at the G1 phase.

2. CDK1 is a protein that in humans is encoded by the CDK1 gene. It is a member of the Ser/Thr protein kinase family. This protein is a catalytic subunit of the highly conserved protein kinase complex known as M-phase promoting factor (MPF), which is essential for G1/S and G2/M phase transitions of the eukaryotic cell cycle.

3. Bcl-2 (B-cell lymphoma 2), encoded in humans by the BCL2 gene, is the founding member of the Bcl-2 family of regulator proteins that regulate cell death (apoptosis), by either inducing (pro-apoptotic) or inhibiting (anti-apoptotic) apoptosis.

RA549 is likely a specific cell line used in this study, and the 6 Gy treatment refers to the cells being exposed to a certain amount of radiation. The results of the Western blot would show how the expression of these proteins changed in response to this treatment.