Biochemical and Biophysical Research Communications
CD300 antigen like family member G: A novel Ig receptor like protein exclusively expressed on capillary endothelium
Section snippets
Materials and methods
Animals. C57BL/6J mice between 7 and 10 weeks old were obtained from CLEA Japan. All animal experiments were performed in accordance with the Guidelines for the Care and Use of Laboratory Animals in RIKEN.
cDNA clones and plasmid construction. An IMAGE consortium cDNA clone (clone ID No. 4913418) covering the coding sequence of mouse CD300LG-α was obtained from Invitrogen Corp., Carlsbad, CA. To obtain other isoforms of mouse CD300L, oligo(dT) primed cDNAs of the mouse heart were amplified by
Cloning and molecular characterization of CD300LG
To identify the novel Fc receptors for IgA, we made use of large databases of ESTs with Ig domains to identify those which showed homology with a region of the Ig domain conserved significantly between pIgR and Fcα/μR. As a result, we found a mouse Ig receptor like gene that encodes a putative type-I membrane protein containing one Ig domain having approximately 35% identity to those of pIgR and Fcα/μR, respectively. The gene was named CD300 antigen like family member G (CD300LG) or CMRF35
Discussion
In the present study, we demonstrated that CD300LG shows restricted expression on capillary endothelium in mouse, in contrast to the fact that many genes of this family are expressed on a variety of hematopoietic cell types [9], [10], [11], [25], [26], [27], [28], [29]. And human CD300LG transcripts were expressed strongly in the human heart and placenta where capillaries are highly developed. In mouse and human, the CD300L family is located on chromosomes 11 and 17, respectively. Whereas
Acknowledgments
We thank Drs. T. Murakami, A. Yoshino, and K. Kawano for critical reading of the manuscript. This study was supported in part by Grants-in-Aid for Young Scientists (B) (H.T.), Scientific Research (H.O.), Scientific Research in Priority Areas (H.O.), and Protein 3000 Project (H.O.) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
References (31)
- et al.
On the origins of adaptive immunity: innate immune receptors join the tale
Trends Immunol.
(2004) - et al.
Killer immunoglobulin-like receptors
Current Opinion in Immunology
(2004) - et al.
PILRalpha, a novel immunoreceptor tyrosine-based inhibitory motif-bearing protein, recruits SHP-1 upon tyrosine phosphorylation and is paired with the truncated counterpart PILRbeta
J. Biol. Chem.
(2000) - et al.
Expression of functionally active FcRn and the differentiated bidirectional transport of IgG in human placental endothelial cells
Human Immunol.
(2001) - et al.
DIgR1, a novel membrane receptor of the immunoglobulin gene superfamily, is preferentially expressed by antigen-presenting cells
Biochem. Biophys. Res. Commun.
(2001) - et al.
The inhibitory receptor IRp60 (CD300a) suppresses the effects of IL-5, GM-CSF, and eotaxin on human peripheral blood eosinophils
Blood
(2006) - et al.
FcRn: the MHC class I-related receptor that is more than an IgG transporter
Immunol. Today
(1997) - et al.
Innate and adaptive immunity: specificities and signaling hierarchies revisited
Nat. Immunol.
(2005) - et al.
Cloning of novel immunoglobulin superfamily receptors expressed on human myeloid and lymphoid cells: structural evidence for new stimulatory and inhibitory pathways
Eur. J. Immunol.
(1997) - et al.
An extended family of Fc receptor relatives
Eur. J. Immunol.
(2005)
A family of proteins that inhibit signalling through tyrosine kinase receptors
Nature
Trems in the immune system and beyond
Nat. Rev. Immunol.
CMRF-35-like molecule-1, a novel mouse myeloid receptor, can inhibit osteoclast formation
J. Immunol.
Molecular cloning of a novel member of the immunoglobulin gene superfamily homologous to the polymeric immunoglobulin receptor
Eur. J. Immunol.
The CMRF-35 mAb recognizes a second leukocyte membrane molecule with a domain similar to the poly Ig receptor
Int. Immunol.
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