Siglec-9, a novel sialic acid binding member of the immunoglobulin superfamily expressed broadly on human blood leukocytes

200Citations
Citations of this article
125Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Here we characterize the properties and expression pattern of Siglec-9 (sialic acid-binding Ig-like lectin-9), a new member of the Siglec subgroup of the immunoglobulin superfamily. A full-length cDNA encoding Siglec-9 was isolated from a dibutyryl cAMP-treated HL-60 cell cDNA library. Siglec-9 is predicted to contain three extracellular immunoglobulin-like domains that comprise an N-terminal V-set domain and two C2-set domains, a transmembrane region and a cytoplasmic tail containing two putative tyrosine-based signaling motifs. Overall, Siglec-9 is ~80% identical in amino acid sequence to Siglec-7, suggesting that the genes encoding these two proteins arose relatively recently by gene duplication. Binding assays showed that, similar to Siglec-7, Siglec-9 recognized sialic acid in either the α2,3- or α2,6-glycosidic linkage to galactose. Using a specific mAb, Siglec-9 was found to be expressed at high or intermediate levels by monocytes, neutrophils, and a minor population of CD16+, CD56- cells. Weaker expression was observed on ~50% of B cells and NK cells and minor subsets of CD8+ T cells and CD4+ T cells. These results show that despite their high degree of sequence similarity, Siglec-7 and Siglec-9 have distinct expression profiles.

Cite

CITATION STYLE

APA

Zhang, J. Q., Nicoll, G., Jones, C., & Crocker, P. R. (2000). Siglec-9, a novel sialic acid binding member of the immunoglobulin superfamily expressed broadly on human blood leukocytes. Journal of Biological Chemistry, 275(29), 22121–22126. https://doi.org/10.1074/jbc.M002788200

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free