Correct immunoglobulin alpha mRNA processing depends on specific sequence in the C alpha 3-alpha M intron

The maturation of IgM-expressing B cells to IgM-secreting plasma cells is associated with both an increase in mu mRNA and the ratio of secreted to membrane forms of mu mRNA which differ at the 3' termini. In contrast, both in vitro and in vivo the secreted form of alpha mRNA is predominant at a...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of immunology (1950) 2000-04, Vol.164 (7), p.3659-3665
Main Authors: Coyle, J H, Lebman, D A
Format: Article
Language:English
Subjects:
Base Sequence
Burkitt Lymphoma
Gene Rearrangement, B-Lymphocyte, Heavy Chain
Humans
Immunoglobulin alpha-Chains - biosynthesis
Immunoglobulin alpha-Chains - genetics
Immunoglobulin alpha-Chains - metabolism
Immunoglobulin Constant Regions - biosynthesis
Immunoglobulin Constant Regions - genetics
Immunoglobulin Constant Regions - metabolism
Introns - genetics
Molecular Weight
Poly A - genetics
Poly A - metabolism
Receptors, Antigen, B-Cell - genetics
Receptors, Antigen, B-Cell - metabolism
RNA Precursors - metabolism
RNA Processing, Post-Transcriptional - genetics
RNA Processing, Post-Transcriptional - immunology
RNA, Messenger - metabolism
Signal Transduction - genetics
Signal Transduction - immunology
Tumor Cells, Cultured
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The maturation of IgM-expressing B cells to IgM-secreting plasma cells is associated with both an increase in mu mRNA and the ratio of secreted to membrane forms of mu mRNA which differ at the 3' termini. In contrast, both in vitro and in vivo the secreted form of alpha mRNA is predominant at all stages in the development of a secretory IgA response. Previous studies demonstrated that preferential usage of the alpha s poly(A) site does not result from transcription termination and is independent of either the poly(A) sites or the 3' splice site associated with the exon encoding the membrane exon of IgA (alpha M). The present study demonstrates that a 349-bp region located 774 bp 3' to the alpha s poly(A) site is required for the preferential usage of the alpha s terminus. This region, which is the first isotype-specific cis-acting regulatory sequence not immediately adjacent to a secretory poly(A) site to be identified, contains regulatory elements that increase the efficiency of polyadenylation/cleavage. A ubiquitous, approximately 58-kDa RNA-binding protein interacts specifically with this regulatory region. These studies support the premise that cis-acting elements unique to each CH gene can impinge upon a common mechanism regulating Ig mRNA processing.
ISSN:0022-1767