presenilin

Function

• PS1 & PS2 are involved in the Notch signalling pathway
• PS1 contains aspartyl protease activity of APP gamma secretase; PS2 may have a similar role
• proteins that interact with presenilins include:
  • nicastrin
  • catenins (alpha?, beta & gamma)
  • cadherins
  • calsenilin
  • PARL, DOCK3, KCNIP4
• putative substrates* for aspartyl protease activity include:
  • amyloid precursor protein (APP) {gamma-secretase}
  • amyloid precursor-like proteins (APLP1 & APLP2)
  • notch-homolog protein
  • Ire-1 protein

* specifity may be broad, including many single transmembrane proteins that undergo cytoplasmic domain release from membrane

Structure

• PS1 & PS2 contain 7-9 transmembrane domains, most likely 8
• presenilins are similar to C elegans sel-12 gene (suppressor &/or enhancer of lin-12)

Compartment

• PS1 & PS2 are associated with membranes of the secretory pathway & appear to be involved in protein trafficking, but may also be associated with the plasma membrane.

Pathology

• presenilins PS-1 &/or PS-2 are found as components of neurofibrillary tangles, but not neuropil threads or dystrophic neurites (as determined by immunohistochemical staining with antibodies raised to sequences shared by PS-1 & PS-2)

More general terms

• membrane protein
• glycoprotein
• enzyme catalytic subunit

More specific terms

• presenilin-1; PS-1; EC=3.4.23.-; protein S182; contains: presenilin-1 NTF subunit; contains: presenilin-1 CTF subunit; contains: presenilin-1 CTF12; PS1-CTF12 (PSEN1, AD3, PS1, PSNL1)
• presenilin-2; PS-2; STM-2; E5-1; AD3LP; AD5; contains: presenilin-2 NTF subunit; contains: presenilin-2 CTF subunit (PSEN2, AD4, PS2, PSNL2, STM2)

Additional terms

• APP gamma-secretase
• presenilin-like protein