Related Experiment Video
Updated: Aug 10, 2026
Combined Immunofluorescence and DNA FISH on 3D-preserved Interphase Nuclei to Study Changes in 3D Nuclear Organization
Published on: February 3, 2013
Deletion of a B-cell-specific enhancer affects transfected, but not endogenous, immunoglobulin heavy-chain gene
A transcriptional enhancer has recently been identified between the variable and constant region coding segments of an assembled immunoglobulin heavy-chain gene. This enhancer is required for efficient expression of such genes when transfected into myeloma cells. A class switch rearrangement in the mouse myeloma cell line 9.9.2.1 has resulted in deletion of this enhancer, and yet this cell line continues to produce heavy chains at a high level. Cell line 9.9.2.1 is a gamma 2a-producing class-switch variant derived from the gamma 2b-producing myeloma cell line, MPC11. We demonstrate that despite the high level of heavy-chain production in 9.9.2.1, the cloned 9.9.2.1 heavy-chain gene is not expressed efficiently when transfected into myeloma cells. Efficient expression after transfection can be obtained only if the deleted enhancer is reinserted into the gene. The implication of this finding for the role of this enhancer in establishing and/or maintaining immunoglobulin heavy-chain gene expression is discussed.
A transcriptional enhancer has recently been identified between the variable and constant region coding segments of an assembled immunoglobulin heavy-chain gene. This enhancer is required for efficient expression of such genes when transfected into myeloma cells. A class switch rearrangement in the mouse myeloma cell line 9.9.2.1 has resulted in deletion of this enhancer, and yet this cell line continues to produce heavy chains at a high level. Cell line 9.9.2.1 is a gamma 2a-producing class-switch variant derived from the gamma 2b-producing myeloma cell line, MPC11. We demonstrate that despite the high level of heavy-chain production in 9.9.2.1, the cloned 9.9.2.1 heavy-chain gene is not expressed efficiently when transfected into myeloma cells. Efficient expression after transfection can be obtained only if the deleted enhancer is reinserted into the gene. The implication of this finding for the role of this enhancer in establishing and/or maintaining immunoglobulin heavy-chain gene expression is discussed.
More Related Videos
11:31Generating CRISPR/Cas9 Mediated Monoallelic Deletions to Study Enhancer Function in Mouse Embryonic Stem Cells
Published on: April 2, 2016
08:22Retroviral Overexpression of CXCR4 on Murine B-1a Cells and Adoptive Transfer for Targeted B-1a Cell Migration to the Bone Marrow and IgM Production
Published on: May 31, 2020
