There are many superfamilies of adhesion proteins, which play a central role in cell‐cell adhesion in animals. Ig superfamily proteins are one such adhesion proteins. Which one of the following statements about Ig superfamily proteins is INCORRECT?
1
The white blood cell proteins recognized by endothelial cell integrins are called ICAM (intercellular cell adhesion molecule) or VCAM (vascular cell adhesion molecules)
2
These are called Ig superfamily because they contain one or more extracellular Ig‐like domains that are characteristic of antibody molecules.
3
ICAM and VCAM mediate heterotrophic binding to integrin, whereas NCAM (neural cell adhesion molecule) mediates homotrophic binding.
4
They contain large quantities of sialic acid which inhibit adhesion by charge‐based repulsion contributing to fine tuning of cell‐cell adhesion.