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The RNA binding protein PTBP1 is necessary for B cell selection in germinal centres

ABSTRACT: Antibody affinity maturation occurs in germinal centres (GC) where B cells cycle between the light zone (LZ) and the dark zone. In the LZ GC B cells bearing immunoglobulins with the highest affinity for antigen receive positive selection signals from T helper cells that promotes their rapid proliferation. Here we show that the RNA binding protein PTBP1 is necessary for the progression of GC B cells through late S-phase of the cell cycle and for affinity maturation. PTBP1 is required for the expression of the c-MYC-dependent gene programme induced in GC B cells receiving T cell help and directly regulates the alternative splicing of transcripts increased during positive selection to promote anabolic metabolism and cell proliferation.

ORGANISM(S): Mus musculus

PROVIDER: GSE100969 | GEO | 2017/12/06

SECONDARY ACCESSION(S): PRJNA393564

REPOSITORIES: GEO

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