Alternative splicing of the human MUC2 gene.
Human colon cancers differ in amounts of MUC2 mucin synthesized. However, it is unclear whether MUC2 encodes a single protein. When clones of human colon cancer cells were assayed with antibodies against the TR2 mucin repeat or non-TR2 epitopes, differences in relative expression of MUC2 proteins suggested multiple immunoreactive forms. RT-PCR analysis detected the established 15kbp MUC2 cDNA and a novel form (designated MUC2.1) lacking the MUC2 TR2 repeat. Sequencing of cDNA and genomic DNA indicated that MUC2.1 results from an alternate splice donor. RT-PCR with splice-junction spanning primers confirmed the expression of MUC2.1 mRNA. Anti-MUC2.1 antibody stained colon cancer cells and normal colon in a pattern different from TR2-specific antibody. The presence of MUC2.1 mucin may help us to explain previous conflicting reports that have attempted to correlate the relative abundance of MUC2 protein and/or mRNA with the biological behavior of colon cancer cells.
Sternberg
Lawrence R
LR
Gastrointestinal Cancer Research Laboratory, Henry Ford Health Sciences Center, 2799 West Grand Blvd, Detroit, MI 48202, USA.
Byrd
James C
JC
Hansson
Gunnar C
GC
Liu
Kai-Feng
KF
Bresalier
Robert S
RS
D017398:Alternative Splicing / Q000235:genetics; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism; D003110:Colonic Neoplasms / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D000939:Epitopes / Q000032:analysis; D005091:Exons / Q000235:genetics; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D055262:Mucin-2; D009077:Mucins / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
D000911:Antibodies, Monoclonal; D017931:DNA Primers; D018076:DNA, Complementary; D000939:Epitopes; C524625:MUC2 protein, human; D055262:Mucin-2; D009077:Mucins; D020033:Protein Isoforms; D012333:RNA, Messenger