Structure, expression, and genetic linkage of the mouse BCM1 (OX45 or Blast-1) antigen. Evidence for genetic duplication giving rise to the BCM1 region on mouse chromosome 1 and the CD2/LFA3 region on mouse chromosome 3.

The mouse BCM1 (OX45, Blast-1) antigen has been cDNA cloned and sequenced to provide data supporting the view that BCM1, LFA3, and CD2 constitute a subgroup within the Ig superfamily. Mouse BCM1 is widely expressed on leukocytes and is likely to be anchored to the cell surface by a glycosyl-phosphatidylinositol anchor, as is the case for rat and human BCM1 antigen. Genetic linkage studies by recombination and pulse field analysis showed the BCM1 locus (Bcm-1) to be on distal mouse chromosome 1 and to be linked within 1,600 kb to the locus for an ATPase alpha chain gene (Atpa-3). A similar relationship was established between the human BCM1 locus (BCM1) and ATP1A2, and other markers on chromosome 1q. Conservation of genomic organization within a segment of human chromosome 1q and mouse chromosome 1 was demonstrated. A similar situation is seen in the region of the CD2 and LFA3 genes between mouse chromosome 3 and human chromosome 1p. Furthermore, the CD2/LFA3 genes are linked within 580 kb to Atpa-1/ATP1A1 genes to provide a parallel situation to the linkage between Bcm-1/BCM1 and Atpa-3/ATP1A2 on chromosomes 1 (mouse) and 1q (human). Taken together, the data suggest duplication of a chromosome region including the precursors of the genes for BCM1, CD2, and LFA3, and the ATPase genes to give rise to the linkage groups now observed. The duplicated regions may have stayed together on chromosome 1 in the human (with the insertion of a centromere), while in the mouse, the genetic regions are proposed to have become dispersed in the formation of chromosomes 1 and 3. CD2 and LFA3 are more dissimilar in sequence than BCM1 and LFA3, and if the precursors of the CD2 and LFA3 loci formed before the proposed chromosome segment duplication, then a gene encoding a recognizer molecule for BCM1 may exist in linkage with Bcm-1/BCM1 on chromosome 1 (mouse) and 1q (human).

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Genomic organization of the selectin family of leukocyte adhesion molecules on human and mouse chromosome 1.

Journal of Experimental Medicine ◽

10.1084/jem.172.1.263 ◽

1990 ◽

Vol 172 (1) ◽

pp. 263-272 ◽

Cited By ~ 112

Author(s):

M L Watson ◽

S F Kingsmore ◽

G I Johnston ◽

M H Siegelman ◽

M M Le Beau ◽

...

Keyword(s):

Human Chromosome ◽

Mouse Chromosome ◽

Leukocyte Adhesion ◽

Evolutionary Relationship ◽

Coagulation Factor ◽

Chromosome 1 ◽

Range Restriction ◽

Human Chromosome 1 ◽

Human And Mouse ◽

Mouse Chromosome 1

A structurally and functionally related group of genes, lymph node homing receptor (LHR), granule membrane protein 140 (GMP-140), and endothelial leukocyte adhesion molecule 1 (ELAM-1) are shown to constitute a gene cluster on mouse and human chromosome 1. In situ hybridization mapped GMP-140 to human chromosome 1 bands 21-24 consistent with chromosomal localization of LHR. Gene linkage analysis in the mouse indicated that these genes and serum coagulation factor V (FV) all map to a region of distal mouse chromosome 1 that is syntenic with human chromosome 1, with no crossovers identified between these four genes in 428 meiotic events. Moreover, long range restriction site mapping demonstrated that these genes map to within 300 kb in both the human and mouse genomes. These data suggest that LHR, ELAM-1, and GMP-140 comprise an adhesion protein family, the selectins, that arose by multiple gene duplication events before divergence of mouse and human. Furthermore, the location of these genes on mouse and human chromosome 1 is consistent with a close evolutionary relationship to the complement receptor-related genes, which also are positioned on the same chromosomes in both species and with which these genes share a region of sequence homology. These data characterize the organization of a genomic region that may be critical for intercellular communication within the immune system.

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