DNA damage response signaling does not trigger redistribution of SAMHD1 to nuclear foci

Ana Carla Medeiros; Claudia S Soares; Priscila O Coelho; Nichelle A Vieira; Munira M A Baqui; Felipe R Teixeira; Marcelo D Gomes

doi:10.1016/j.bbrc.2018.03.225

DNA damage response signaling does not trigger redistribution of SAMHD1 to nuclear foci

Biochem Biophys Res Commun. 2018 May 23;499(4):790-796. doi: 10.1016/j.bbrc.2018.03.225. Epub 2018 Apr 5.

Authors

Ana Carla Medeiros¹, Claudia S Soares¹, Priscila O Coelho¹, Nichelle A Vieira¹, Munira M A Baqui², Felipe R Teixeira³, Marcelo D Gomes⁴

Affiliations

¹ Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Brazil.
² Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, Brazil.
³ Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Brazil; Ribeirao Preto Medical School, University of São Paulo, and Department of Genetics and Evolution, Federal University of Sao Carlos, Brazil. Electronic address: [email protected].
⁴ Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Brazil. Electronic address: [email protected].

PMID: 29614270
DOI: 10.1016/j.bbrc.2018.03.225

Abstract

SAMHD1 (Sterile alpha motif and histidine-aspartic acid (HD) domain containing protein 1) is a deoxyribonucleoside triphosphate (dNTP) triphosphohydrolase (dNTPase) that restricts viral replication in infected cells. This protein is also involved in DNA repair by assisting in DNA end resection by homologous recombination (HR) after DNA double-strand break (DSB) induction with camptothecin (CPT) or etoposide (ETO). We showed that a monoclonal anti-SAMHD1 antibody produced against the full-length protein detected an unspecific 50 kDa protein that colocalized with dot-like structures after CPT treatment in HeLa cells. In contrast, a polyclonal anti-SAMHD1 antibody raised against the N-terminus of this protein specifically detected SAMHD1, as shown in Jurkat, HAP1^KO and HEK293T SAMHD1-siRNA cell lysates compared with their respective controls. Our findings showed that SAMHD1 is not localized in dot-like structures under DSB induction in HeLa cells.

Keywords: Alternative translation initiation site (TIS); DNA double-strand break (DSB) induction; SAMHD1.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antibody Specificity
Cell Extracts
Cell Line
Cell Nucleus / metabolism*
DNA Damage*
Humans
Peptide Chain Initiation, Translational
SAM Domain and HD Domain-Containing Protein 1 / metabolism*
Signal Transduction*

Substances

Cell Extracts
SAM Domain and HD Domain-Containing Protein 1
SAMHD1 protein, human