paired immunoglobulin-like type 2 receptor alpha (inhibitory receptor PILR-alpha, cell surface receptor FDF03, PILRA)

Function

• paired receptors consist of highly related activating & inhibitory receptors
• role in regulation of the immune system
• PILRA is thought to act as a cellular signaling inhibitory receptor by recruiting cytoplasmic phosphatases, including PTPN6/SHP-1 & PTPN11/SHP-2 via their SH2 domains that block signal transduction through dephosphorylation of signaling molecules
• interacts with PTPN6/SHP-1 & PTPN11/SHP-2 upon Tyr phosphorylation

Structure

• monomer
• contains 2 copies of ITIM motif
  • PTPN6 seems to bind predominantly to the 1st ITIM motif.
• N- & O-glycosylated
• phosphorylated on Tyr
• contains 1 Ig-like V-type domain (immunoglobulin-like)

Compartment

• isoforms 1 & 2: cell membrane
• isoforms 3 & 4: secreted

Alternative splicing

named isoforms=4

Expression

• predominantly detected in hemopoietic tissues
  • expressed by monocytes, macrophages, granulocytes, but not lymphocytes
• strongly expressed by dendritic cells
  • preferentially expressed by CD14+/CD1a- derived from CD34+ dentritic cell progenitors
  • also expressed by CD11c+ blood & tonsil dentritic cells, but not by CD11c- dentritic cell precursors

More general terms

• cell surface receptor

Additional terms

• paired immunoglobulin-like type 2 receptor beta (activating receptor PILR-beta, cell surface receptor FDFACT, PILRB FDFACT, PP1551)

Database

• OMIM: https://mirror.omim.org/entry/605341
• UniProt: http://www.uniprot.org/uniprot/Q9UKJ1.html