Gene structure and transcript analysis of the human and mouse EGF-TM7 molecule, FIRE.
The epidermal growth factor-transmembrane seven (EGF-TM7) family are proteins that express EGF-like domains at their extracellular N-terminus coupled to a classical seven transmembrane (TM7) cassette. Recently, we identified, in mice, a novel member of this family termed FIRE (EMR-4). Here, we present the structure of the mouse and human FIRE genes. The structures of the two genes are strikingly similar, with the positions of the introns, relative to the deduced protein sequences, highly conserved. Moreover, the gene structures are typical of other members of the EGF-TM7 family. Other researchers have identified a point deletion in exon eight of the human FIRE gene, which introduces a frame shift into the cDNA leading to a premature stop codon. Thus, human FIRE is predicted to be expressed only as a soluble protein; even though sequence potentially encoding the TM7 cassette is found in a separate open reading frame of the same mRNA transcript. We explored the possibility that a cell surface expressed form of human FIRE did exist, either as an allelic variant, or as an alternatively spliced transcript. Although, we did identify two alternatively spliced human FIRE transcripts, neither are predicted to express the TM7 cassette. Thus if human FIRE exists, it is likely to be expressed as a soluble secreted molecule.
Caminschi
Irina
I
The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, 3050, Vic., Australia.
Vandenabeele
Stephane
S
Sofi
Mariam
M
McKnight
Andrew J
AJ
Ward
Neil
N
Brodnicki
Thomas C
TC
Toy
Tracey
T
Lahoud
Mireille
M
Maraskovsky
Eugene
E
Shortman
Ken
K
Wright
Mark D
MD
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D004815:Epidermal Growth Factor / Q000235:genetics*; D020869:Gene Expression Profiling; D014644:Genetic Variation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms; D043562:Receptors, G-Protein-Coupled / Q000235:genetics*; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein
C483023:ADGRE4P protein, human; C464944:Emr4 protein, mouse; D020033:Protein Isoforms; D043562:Receptors, G-Protein-Coupled; D004815:Epidermal Growth Factor