Human homologs of the Xenopus oocyte cortical granule lectin XL35.
The cDNAs encoding two human homologs of the Xenopus oocyte lectin, XL35, were isolated from a small intestine cDNA library and termed HL-1 and HL-2. The deduced amino acid sequence of each homolog is about 60% identical and 80% similar to that of XL35, and none of these sequences contains the C-type lectin motif, although it is known that XL35 requires calcium for ligand binding. By Northern analysis, HL-1 transcripts are present at relatively high levels in heart, small intestine, colon, thymus, ovary, and testis. HL-2 transcripts, by contrast, are expressed only in small intestine. Immunocytochemistry using a polyclonal antibody produced against XL35 shows HL-1 protein to be localized exclusively in endothelial cells in colon, thymus, liver, and other tissues. Primary cultures of human aortic endothelial cells are positive for HL-1 expression by immunoblotting and by PCR analysis, but several other human cell types are not. HL-1 and -2 are both encoded at chromosome 1q23, the same locus that encodes the selectins. XL35, HL-1 and -2, and another mouse homolog are members of a new family of proteins whose members most likely perform diverse functions.
Lee
J K
JK
Department of Pathology, Division of Cardiology, UCLA Medical School, Los Angeles, CA, USA.
Schnee
J
J
Pang
M
M
Wolfert
M
M
Baum
L G
LG
Moremen
K W
KW
Pierce
M
M
D000818:Animals; D002874:Chromosome Mapping; D018076:DNA, Complementary; D006801:Humans; D007150:Immunohistochemistry; D037102:Lectins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D029867:Xenopus Proteins; D014982:Xenopus laevis
D018076:DNA, Complementary; C484562:ITLN2 protein, human; D037102:Lectins; D012333:RNA, Messenger; C106471:XL35 protein, Xenopus; D029867:Xenopus Proteins