Rapid, Antibody-Free Detection of Recombinant Proteins on Blots Using Enzyme Fragment Complementation.

Alternative, antibody-free techniques to western analysis of protein blots can offer reduced assay times for routine analysis of expression of recombinant proteins. We have adapted the commercially available enzyme fragment complementation technology to provide a rapid protein detection method for protein blots based on significantly reducing the number of incubation and washing steps used in traditional approaches, and eliminating the requirement for antibodies. In this chapter, we highlight the use of this assay for measuring recombinant protein expressed in mammalian cells for a range of applications, including dot blot screening of large numbers of different cell samples, assessment of protein integrity through detection of degradation bands, and characterization of posttranslational protein modifications such as glycosylation.

Rapid, antibody-free detection of recombinant proteins on blots using enzyme fragment complementation.

Alternative, antibody-free techniques to western analysis of protein blots can offer reduced assay times for routine analysis of expression of recombinant proteins. We have adapted the commercially available enzyme fragment complementation technology to provide a rapid protein detection method for protein blots based on significantly reducing the number of incubation and washing steps used in traditional approaches, and eliminating the requirement for antibodies. In this article, we highlight the use of this assay for measuring recombinant protein expressed in mammalian cells for a range of applications, including dot blot screening of large numbers of different cell samples, assessment of protein integrity through detection of degradation bands, and characterization of post-translational protein modifications such as glycosylation.

Inhibition of phosphatidylinositol-3-kinase causes increased sensitivity to radiation through a PKB-dependent mechanism.

Purpose: To identify whether inhibition of phosphatidylinositol-3-kinase (PI3K) causes increased radiosensitivity through inhibition of protein kinase B (PKB), implicating PKB as an important therapeutic target in prostate cancer.

Methods And Materials: The prostate cancer cell line LNCaP was treated with the PI3K inhibitor LY294002, radiation, and combinations of the two therapies. Apoptosis and survival were measured by cell cycle analysis, Western blot analysis for cleaved poly (ADP-ribose) polymerase, and clonogenic survival.

Inhibition of phosphatidylinositol-3-kinase causes cell death through a protein kinase B (PKB)-dependent mechanism and growth arrest through a PKB-independent mechanism.

Purpose: To identify whether inhibition of phosphatidylinositol-3-kinase (PI3K) causes apoptosis through inhibition of protein kinase B (PKB), implicating PKB as an important therapeutic target in prostate cancer.

Methods And Materials: After treatment with the PI3K inhibitor, LY294002, proliferation and apoptosis of the prostate cancer cell line, LNCaP, were measured by cell cycle analysis and cleavage of poly (ADP-ribose) polymerase. To test the hypothesis that inhibition of PKB is responsible for the LY294002-induced apoptosis, LNCaP cells expressing a constitutively active form of PKB were generated.