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NME proteins regulate class switch recombination.

ABSTRACT: Class switch recombination (CSR) in B cells involves deletion-recombination at switch (S) region DNA and is important for the diversification of antibody isotypes during an immune response. Here, we identify two NME [NM23/NDPK (nucleoside diphosphate kinase)] isoforms, NME1 and NME2, as novel players in this process. Knockdown of NME2 leads to decreased CSR, while knockdown of the highly homologous NME1 results in increased CSR. Interestingly, these NME proteins also display differential occupancy at S regions during CSR despite their homology; NME1 binds to S regions prior to stimulation, while NME2 binds to S regions only after stimulation. To the best of our knowledge, this represents the first report of a role for these proteins in the regulation of CSR.

SUBMITTER: Zheng S

PROVIDER: S-EPMC6333498 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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NME proteins regulate class switch recombination.

Zheng Simin S Kusnadi Anthony A Choi Jee Eun JE Vuong Bao Q BQ Rhodes Daniela D Chaudhuri Jayanta J

FEBS letters 20181123 1

Class switch recombination (CSR) in B cells involves deletion-recombination at switch (S) region DNA and is important for the diversification of antibody isotypes during an immune response. Here, we identify two NME [NM23/NDPK (nucleoside diphosphate kinase)] isoforms, NME1 and NME2, as novel players in this process. Knockdown of NME2 leads to decreased CSR, while knockdown of the highly homologous NME1 results in increased CSR. Interestingly, these NME proteins also display differential occupan ...[more]

PMID: 30411342

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