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The cell-cycle regulator c-Myc is essential for the formation and maintenance of germinal centers.

ABSTRACT: Germinal centers (GCs) are sites of intense B cell proliferation and are central for T cell-dependent antibody responses. However, the role of c-Myc, a key cell-cycle regulator, in this process has been questioned. Here we identified c-Myc(+) B cell subpopulations in immature and mature GCs and found, by genetic ablation of Myc, that they had indispensable roles in the formation and maintenance of GCs. The identification of these functionally critical cellular subsets has implications for human B cell lymphomagenesis, which originates mostly from GC B cells and frequently involves MYC chromosomal translocations. As these translocations are generally dependent on transcription of the recombining partner loci, the c-Myc(+) GC subpopulations may be at a particularly high risk for malignant transformation.

SUBMITTER: Calado DP

PROVIDER: S-EPMC4132664 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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The cell-cycle regulator c-Myc is essential for the formation and maintenance of germinal centers.

Calado Dinis Pedro DP Sasaki Yoshiteru Y Godinho Susana A SA Pellerin Alex A Köchert Karl K Sleckman Barry P BP de Alborán Ignacio Moreno IM Janz Martin M Rodig Scott S Rajewsky Klaus K

Nature immunology 20120923 11

Germinal centers (GCs) are sites of intense B cell proliferation and are central for T cell-dependent antibody responses. However, the role of c-Myc, a key cell-cycle regulator, in this process has been questioned. Here we identified c-Myc(+) B cell subpopulations in immature and mature GCs and found, by genetic ablation of Myc, that they had indispensable roles in the formation and maintenance of GCs. The identification of these functionally critical cellular subsets has implications for human ...[more]

PMID: 23001146

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