Fig. 4

CEACAM50 has unique signaling motifs within the CEA gene family. The exon structure of the CEACAM50 gene indicates that its gene product may contain an ITIM signaling motif. However as shown in a the cloned mRNA demonstrate that an alternative splice donor site of the transmembrane exon is used and that the exons C1 and C2 were not integrated into the mRNA. b shows the possible but unused splice donor site (underlined). c Amino acid sequence of the transmembrane and cytoplasmic part of CEACAM50. The PKA phosphorylation site is highlighted in blue, further phosphorylation sites were indicated in bold. d Expression of CEACAM50 was detected in various parts of the intestine. e Expression of CEACAM50 fused to a FLAG-tag at the N-terminus by transfected Cos7L. Red stars indicate the presence of a stop codon