Critical role of Pcid2 in B cell survival through the regulation of MAD2 expression.
The mitotic checkpoint is essential for maintaining genomic stability in differentiating B cells undergoing genetic alterations of the Ig gene. In this study, using real-time RT-PCR and in situ RNA hybridization, we demonstrated that MAD2 mRNA export is selectively regulated by Pcid2/Thp1. Pcid2 small interfering RNA induced a cell-cycle abnormality with increased apoptosis and polyploidy, as previously observed in MAD2-knockdown cells. Pcid2 small interfering RNA reduced MAD2 expression, but not the expression of other cell-cycle checkpoint proteins, such as MAD1 and BUBR1, or the cell-cycle-associated proteins, cyclin A, cyclin B1, and cyclin-dependent kinase 1. In mouse B lineage cells, Pcid2 transcripts appeared in a stage-dependent manner at high levels in bone marrow pre-B and immature B cells, and in spleen transitional 1 and follicular B cells, but at lower levels in pro-B, transitional 2, and marginal zone B cells, suggesting a stage-dependent requirement for MAD2 regulation. Cd19-cre-derived targeting of the Pcid2 gene induced a mature B cell deficiency in mice. These findings indicate that Pcid2 is essential for B cell survival through the regulation of MAD2 expression during B cell differentiation.
Nakaya
Teruo
T
Department of Immunology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
Kuwahara
Kazuhiko
K
Ohta
Kazutaka
K
Kitabatake
Masahiro
M
Toda
Teppei
T
Takeda
Naoki
N
Tani
Tokio
T
Kondo
Eisaku
E
Sakaguchi
Nobuo
N
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D002453:Cell Cycle / Q000235:genetics / Q000276:immunology; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D002454:Cell Differentiation / Q000276:immunology; D002470:Cell Survival / Q000235:genetics / Q000276:immunology; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000276:immunology*; D015151:Immunoblotting; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D064246:Mad2 Proteins; D051379:Mice; D018345:Mice, Knockout; D034741:RNA, Small Interfering; D020133:Reverse Transcriptase Polymerase Chain Reaction
D018797:Cell Cycle Proteins; D064246:Mad2 Proteins; C577698:Mad2l1 protein, mouse; D034741:RNA, Small Interfering