Siglecs are I-type (Ig-type) lectins belonging to the Ig superfamily. They are characterized by an N-terminal, Ig-like V-type domain that mediates sialic acid binding, followed by varying numbers of Ig-like C2-type domains (2 to 17), a single transmembrane region, and a cytoplasmic tail. The siglecs can be broadly classified into two subgroups: Siglecs-1, -2, and -4, and a Siglec-3/CD33-related subgroup (Siglecs-3, and -5 through -13 in primates) defined by sequence similarity and clustered gene localization. They are widely expressed on hematopoietic cells, often in a cell-type-specific manner, and Siglec-4/MAG is a myelin component in Schwann cells and oligodendrocytes. Their ligands, sialic acids, are negatively charged monosaccharides found on cell-surface glycoproteins and glycolipids. Although Siglec functions continue to be defined, most have intracellular immunoreceptor tyrosine-based inhibitory motifs (ITIM), implicating them in the suppression of immunoreceptor signaling. They may also participate in cell/cell interactions or act as receptors for the entry of viral or bacterial pathogens.
PRODUCT AVAILABILITY: Update Regarding the Evolving COVID-19 Situation
Bio-Techne appreciates the critical role that you and our products and services play in research efforts to further scientific innovation and discovery. We are continually assessing our manufacturing and supplier capabilities during the COVID-19 situation and are implementing precautionary measures to ensure uninterrupted supply of products and services. Currently, and as we abide by local shelter in place orders across the world, we are fully operational and do not anticipate any material supply disruptions across our Bio-Techne brands and product lines. As the situation evolves, our goal is to utilize preventive measures to reduce the threat that COVID-19 poses to our ability to meet the needs of our customers globally.