Chromosomal position of rearranging gene segments influences allelic exclusion in transgenic mice.

Conserved differences between the transmembrane and cytoplasmic domains of membrane immunoglobulin (Ig)M and IgG may alter the function of antigen receptors on naive versus memory B cells. Here, we compare the ability of these domains to signal B cell allelic exclusion and maturation in transgenic mice. A lysozyme-binding antibody was expressed in parallel sets of mice as IgM, IgG1, or a chimeric receptor with IgM extracellular domains and transmembrane/cytoplasmic domains of IgG1. Like IgM, the IgG1 or chimeric IgM/G receptors triggered heavy chain allelic exclusion and supported development of mature CD21+ B cells. Many of the IgG or IgM/G B cells became CD21high and downregulated their IgG and IgM/G receptors spontaneously, resembling memory B cells and B cells with mutations that exaggerate B cell antigen receptor signaling. Unlike IgM-transgenic mice, “edited” B cells that carry non–hen egg lysozyme binding receptors preferentially accumulated in IgG and IgM/G mice. This was most extreme in lines with the highest transgene copy number and diminished in variant offspring with fewer copies. The sensitivity of B cell maturation to transgene copy number conferred by the IgG transmembrane and cytoplasmic domains may explain the diverse phenotypes found in other IgG-transgenic mouse strains and may reflect exaggerated signaling.

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Feedback inhibition of immunoglobulin gene rearrangement by membrane mu, but not by secreted mu heavy chains.

Journal of Experimental Medicine ◽

10.1084/jem.168.4.1363 ◽

1988 ◽

Vol 168 (4) ◽

pp. 1363-1381 ◽

Cited By ~ 85

Author(s):

J Manz ◽

K Denis ◽

O Witte ◽

R Brinster ◽

U Storb

Keyword(s):

Gene Expression ◽

Transgenic Mice ◽

B Cell ◽

Cell Lines ◽

Gene Rearrangement ◽

Feedback Inhibition ◽

Allelic Exclusion ◽

Immunoglobulin Gene ◽

Heavy Chains

Previous work (6-10) has shown that allelic exclusion of Ig gene expression is controlled by functionally rearranged mu and kappa genes. This report deals with the comparison of membrane mu (micron) and secreted mu (microsecond) in promoting such feedback inhibition. Splenic B cell hybridomas were analyzed from transgenic mice harboring a rearranged kappa gene alone or in combination with either an intact rearranged mu gene or a truncated version of the mu gene. The intact mu gene is capable of producing both membrane and secreted forms of the protein, while the truncated version can only encode the secreted form. The role of the microsecond was also tested in pre-B cell lines. Analysis of the extent of endogenous Ig gene rearrangement revealed that (a) the production of micron together with kappa can terminate Ig gene rearrangement; (b) microsecond with kappa does not have this feedback effect; (c) microsecond may interfere with the effect of micron and kappa; and (d) the feedback shown here probably represents a complete shutoff of the specific recombinase by micron + kappa; the data do not address the question of mu alone affecting the accessibility of H genes for rearrangement.

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Allelic exclusion in transgenic mice expressing a heavy chain disease-like human μ protein

European Journal of Immunology ◽

10.1002/eji.1830211110 ◽

1991 ◽

Vol 21 (11) ◽

pp. 2711-2716 ◽

Cited By ~ 18

Author(s):

Daniel Corcos ◽

Antonio Iglesias ◽

Olga Dunda ◽

Jacques Jami

Keyword(s):

Transgenic Mice ◽

Heavy Chain ◽

Allelic Exclusion ◽

Heavy Chain Disease

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Allelic exclusion in transgenic mice carrying mutant human IgM genes.

Journal of Experimental Medicine ◽

10.1084/jem.167.6.1969 ◽

1988 ◽

Vol 167 (6) ◽

pp. 1969-1974 ◽

Cited By ~ 26

Author(s):

M C Nussenzweig ◽

A C Shaw ◽

E Sinn ◽

J Campos-Torres ◽

P Leder

Keyword(s):

Transgenic Mice ◽

Heavy Chain ◽

Chain Gene ◽

Allelic Exclusion ◽

Heavy Chain Gene ◽

F1 Hybrid ◽

Membrane Bound ◽

Ig Heavy Chain ◽

Simultaneous Expression

Expression of the membrane-bound version of the human mu chain in transgenic mice results in the allelic exclusion of endogenous mouse Ig heavy chain genes (6). The secreted version of the human Ig transgene has no such effect. F1 hybrid animals that carry transgenes for both secreted and membrane-bound human mu chains produce both forms of the human heavy chain while strongly suppressing endogenous mouse mu expression. The simultaneous expression of the two rearranged transgenes in primary B cells suggests that allelic exclusion operates before the formation of a second functionally rearranged heavy chain gene in vivo.

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Stringent V beta requirement for the development of NK1.1+ T cell receptor-alpha/beta+ cells in mouse liver.

Journal of Experimental Medicine ◽

10.1084/jem.183.3.1277 ◽

1996 ◽

Vol 183 (3) ◽

pp. 1277-1282 ◽

Cited By ~ 53

Author(s):

T Ohteki ◽

H R MacDonald

Keyword(s):

T Cells ◽

T Cell ◽

Transgenic Mice ◽

Beta Cells ◽

T Cell Receptor ◽

Cell Receptor ◽

Allelic Exclusion ◽

Stringent Requirement ◽

Major Subset ◽

Alpha Beta

The liver of C57BL/6 mice contains a major subset of CD4+8- and CD4-8- T cell receptor (TCR)-alpha/beta+ cells expressing the polymorphic natural killer NK1.1 surface marker. Liver NK1.1+TCR-alpha/beta+ (NK1+ T) cells require interaction with beta2-microglobulin-associated, major histocompatibility complex I-like molecules on hematopoietic cells for their development and have a TCR repertoire that is highly skewed to Vbeta8.2, Vbeta7, and Vbeta2. We show here that congenic C57BL/6.Vbeta(a) mice, which lack Vbeta8- expressing T cells owing to a genomic deletion at the Vbeta locus, maintain normal levels of liver NK1+ T cells owing to a dramatic increase in the proportion of cells expressing Vbeta7 and Vbeta2 (but not other Vbetas). Moreover, in C57BL/6 congenic TCR-V Vbeta3 and -Vbeta8.1 transgenic mice (which in theory should not express other Vbeta, owing to allelic exclusion at the TCR-beta locus), endogenous TCR-Vbeta8.2, Vbeta7, and Vbeta2 (but not other Vbetas) are frequently expressed on liver NK1+T cells but absent on lymph node T cells. Finally, when endogenous V beta expression is prevented in TCR-Vbeta3 and Vbeta8.1 transgenic mice (by introduction of a null allele at the C beta locus), the development of liver NK1+T cells is totally abrogated. Collectively, our data indicate that liver NK1+T cells have a stringent requirement for expression of TCR-Vbeta8.2, Vbeta7, or Vbeta2 for their development.

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Expression of a foreign gene in a line of transgenic mice is modulated by a chromosomal position effect.

Molecular and Cellular Biology ◽

10.1128/mcb.10.3.1192 ◽

1990 ◽

Vol 10 (3) ◽

pp. 1192-1198 ◽

Cited By ~ 103

Author(s):

R al-Shawi ◽

J Kinnaird ◽

J Burke ◽

J O Bishop

Keyword(s):

Transgenic Mice ◽

Position Effect ◽

Insertion Site ◽

Foreign Gene ◽

Aberrant Expression ◽

Transgenic Mouse Line ◽

Chromosomal Position ◽

Multiple Copies ◽

Chromosomal Position Effect ◽

Or Gene

Unusual aberrant expression of a foreign gene in a particular transgenic mouse line is often attributed to chromosomal position effect, although proof of this is lacking. An alternative explanation is that expression has been modified by the arrangement of multiple copies of the foreign gene at the insertion site or by mutation or gene rearrangement. We have distinguished between these explanations in the case of one particular transgenic line by recovering the aberrantly expressed foreign DNA and reintroducing it into the mouse genome to produce secondary transgenic mice. The expression pattern of the gene in the secondary transgenic mice was normal, showing that this case of aberrant expression is due to a chromosomal position effect.

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Chromosomal position of a VH gene segment determines its activation and inactivation as a substrate for V(D)J recombination

Journal of Experimental Medicine ◽

10.1084/jem.20071787 ◽

2007 ◽

Vol 204 (13) ◽

pp. 3247-3256 ◽

Cited By ~ 28

Author(s):

Jamie Geier Bates ◽

Dragana Cado ◽

Hector Nolla ◽

Mark S. Schlissel

Keyword(s):

B Cells ◽

Gene Cluster ◽

Gene Targeting ◽

Dna Sequences ◽

Gene Rearrangement ◽

Gene Segment ◽

Allelic Exclusion ◽

Chromosomal Position ◽

Lineage Specificity ◽

Vh Gene

Complete IgHC gene rearrangement occurs only in B cells in a stage-specific and ordered manner. We used gene targeting to reposition a distal VH gene segment to a region just 5′ of the DH gene cluster and found its activation to be highly dependent on the chromosomal domain within which it resides. The targeted VH gene segment rearranged at a higher frequency than its endogenous counterpart, its rearrangement was no longer ordered, and its ability to be silenced by allelic exclusion was lost. Additionally, the targeted VH gene segment lost lineage specificity, as VDJH rearrangement was observed in thymocytes. These data suggest that locus contraction, mimicked by proximal targeting, can override any regulation imposed by DNA sequences immediately surrounding VH gene segments.

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