CD34 is a cell-surface glycoprotein type 1 transmembrane protein that belongs to the sialomucin family. CD34 comprises of an intracellular cytoplasmic domain with consensus sites for serine, threonine, tyrosine and active protein kinase C (PKC). Because it is differentially glycosylated within different cell types, it has a range of apparent molecular weight sizes. It is a marker for pluripotent hematopoietic stem or progenitor cells and has been extensively used to isolate and characterize these progenitor cells.
