Binding of LBP-1a to specific immunoglobulin switch regions in vivo correlates with specific repression of class switch recombination.

ABSTRACT: Upon stimulation of mature B cells, class switch recombination (CSR) can alter the specific immunoglobulin heavy chain constant region that is expressed. In a tissue culture cell line, we previously demonstrated that inhibition of late SV40 factor (LSF) family members enhanced IgM to IgA CSR. Here, isotype specificity of CSR regulation by LSF family members is addressed in primary mouse splenic B cells. First, we demonstrate that leader-binding protein-1a (LBP-1a) is the prevalent family member in B lymphocytes. Second, we demonstrate by ChIP that LBP-1a binds genomic sequences around mouse switch (S) regions in an isotype-specific manner, in accordance with computational predictions: binding is observed to Smu and Salpha, but not to the tested Sgamma1, regions. Importantly, binding of LBP

SUBMITTER: Repetny KJ 

PROVIDER: S-EPMC3407417 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature