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Postmitotic G1 phase survivin drives mitogen-independent cell division of B lymphocytes.

ABSTRACT: B and T lymphocytes of the adaptive immune system undergo proliferative bursts to generate pools of antigen-specific cells for effective immunity. Here we show that in contrast to the canonical view that G1 progression signals are essential after mitosis to reenter S phase, B lymphocytes sustain several rounds of mitogen-independent cell division following the first mitosis. Such division appears to be driven by unique characteristics of the postmitotic G1 phase that has features of S and G2/M phases. Birc5 (survivin), a protein associated with chromosome segregation in G2/M, is expressed in the G1 phase of divided B cells and is necessary for mitogen-independent divisions. The partially active G1 phase and propensity for apoptosis inherited after each division may underlie rapid proliferation and cell death, which are hallmarks of B cell proliferative responses.

SUBMITTER: Singh A

PROVIDER: S-EPMC9170024 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Postmitotic G1 phase survivin drives mitogen-independent cell division of B lymphocytes.

Singh Amit A Spitzer Matthew H MH Joy Jaimy P JP Kaileh Mary M Qiu Xiang X Nolan Garry P GP Sen Ranjan R

Proceedings of the National Academy of Sciences of the United States of America 20220427 18

B and T lymphocytes of the adaptive immune system undergo proliferative bursts to generate pools of antigen-specific cells for effective immunity. Here we show that in contrast to the canonical view that G1 progression signals are essential after mitosis to reenter S phase, B lymphocytes sustain several rounds of mitogen-independent cell division following the first mitosis. Such division appears to be driven by unique characteristics of the postmitotic G1 phase that has features of S and G2/M p ...[more]

PMID: 35476510

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