So Many Plasminogen Receptors: Why?

Table 1

Plg-Rs on various cell types.

Plg-Rs	Cell types	C-terminal lysine	Major cellular localization	Secretory pathways
(1) Annexin A2	Endothelial cells, monocytoid lineage	Absent^*	Cytosol and or nucleus	Translocation depends on p11 and phosphorylation; activity of L-type like Ca^2+ channels and intracellular Ca^2+; associates with plasma membrane via phosphatidylserine.
(2) Actin	Endothelial cells, carcinoma, catecholaminergic cells, PC-3, HT1080	Absent	Cytoskeleton	Not known
(3) Amphoterin	Neuronal cells	Absent	Cytoplasmic and extracellular	Not known
(4) 𝛼V𝛽3	Endothelial cells	Absent	Integral membrane protein	Classical endoplasmic reticulum and Golgi pathway
(5) 𝛼M𝛽2	Neutrophils, monocytes, macrophages	Absent	Integral membrane protein	Classical endoplasmic reticulum and Golgi pathway
(6) 𝛼IIb𝛽3	Platelets, RA synovial fibroblasts	Absent	Integral membrane protein	Classical endoplasmic reticulum and Golgi pathway
(7) Cytokeratin 8	Hepatocellular, breast carcinoma	Present	Cytoskeleton	Not known
(8) 𝛼-Enolase	Monocytes, neutrophils, carcinoma, lymphoid, myoblast neurons	Present	Cytosol	L-type-like Ca^2+ channel and intracellular Ca^2+
(9) Histone 2B	Neutrophils, monocytoid cells, endothelial cells	Present	Nucleus	L-type-like Ca^2+ channel and intracellular Ca^2+. Associates with plasma membrane via phosphatidylserine and heparin sulfate
(10) P11	Endothelial cells, HT1080 cells	Present	Cytosol and or nucleus	L-type-like Ca^2+ channel and intracellular Ca^2+. Associates with multiple plasma membrane binding partners, including annexin 2
(11) Plg-RKT	Monocytes, macrophages, neuronal cells	Present	Integral membrane protein	Classical endoplasmic reticulum and Golgi pathway
(12) TATA-binding protein-interacting protein	Monocytoid cells	Present	Nucleus	Not known

^*requires cleavage to bind Plg [8].