Allelic exclusion of membrane but not secreted immunoglobulin in a mature B cell line.
Allelic exclusion of membrane but not secreted immunoglobulin in a mature B cell line.
复制标题
成熟 B 细胞系中膜的等位基因排斥，但不分泌免疫球蛋白。
DOI：
10.1002/eji.1830210110
复制
发表时间：
1991
影响因子：
5.4
通讯作者：
Rosenberg,N
中科院分区：
文献类型：
--
作者：
Picarella,D;Serunian,LA;Rosenberg,N
Although many B lymphocytes contain two completely rearranged immunoglobulin (Ig) heavy (H) chain genes, only one of the alleles specifies a protein product. This phenomenon is termed allelic exclusion and is controlled in part by the membrane portion of Ig H chains. We have identified a mature B cell line derived from murine bone marrow that expresses two H chain proteins, γ3and γ2b. Proteins of appropriate size for the membrane and secreted forms of both H chains are produced and both IgG3and IgG2bare secreted from the cells. However, only IgG3is expressed on the membrane. Detailed restriction mapping of the H chain genes indicates that both are rearranged, one containing a VHJ558 gene linked to the γ3constant region and the other a VHS107 gene linked to the γ2bconstant region. Primer extension sequencing of the RNA reveals that the γ2bRNA is transcribed from the allele containing VHS107 sequences while the γ3RNA is transcribed from the allele containing VHJ558 sequences. Thus, this mature B cell line secretes two distinct antibody molecules but is allelically excluded at the level of surface Ig expression. This cell line provides a model system to study factors, in addition to aberrant rearrangement, that influence allelic exclusion.
