A re-evaluation of LINE-1 ORF2 expression in LNCaP prostate cancer cells

Erica M Briggs; Corrado Spadafora; Susan K Logan

doi:10.1186/s13100-019-0196-x

A re-evaluation of LINE-1 ORF2 expression in LNCaP prostate cancer cells

Mob DNA. 2019 Dec 29:10:51. doi: 10.1186/s13100-019-0196-x. eCollection 2019.

Authors

Erica M Briggs¹, Corrado Spadafora², Susan K Logan^{1

3}

Affiliations

¹ 1Departments of Biochemistry and Molecular Pharmacology, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, Room 323, New York, NY 10016 USA.
² 3Institute of Translational Pharmacology, National Research Council, Rome, Italy.
³ 2Departments of Urology, New York University School of Medicine, Alexandria Center for Life Sciences, 450 East 29th Street, Room 323, New York, NY 10016 USA.

Abstract

Background: We previously examined expression of Long Interspersed Element-1 (LINE-1) in a variety of prostate cancer cells including hormone-dependent LNCaP cells. These studies demonstrated expression and sub-cellular localization of LINE-1 proteins, ORF1p, with antibody 4H1, and ORF2p, with antibody chA1-L1.

Results: Here we conduct immunoprecipitation/mass spectrometry analysis using chA1-L1 antibody against ORF2p in LNCaP cells. Our results indicate that antigens detected by the antibody include the transcriptional regulator BCLAF1. We show that chA1-L1 recognizes BCLAF1 using siRNA knockdown and overexpression of a tagged BCLAF1. We also show that chA1-L1 antibody recognizes ORF2p in HEK293 cells overexpressing LINE-1. Further, analysis of ORF2p (chA1-L1) and BCLAF1 foci using immunofluorescence in LNCaP cells showed significant colocalization.

Conclusions: Overall, our findings indicate that chA1-L1 antibody recognizes both BCLAF1 and ORF2p but the majority of antigen recognized in LNCaP cells is BCLAF1.

Keywords: BCLAF1; LINE-1; ORF2; ORF2 antibody; Prostate cancer.

Abstract

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