translocon-associated protein subunit alpha; TRAP-alpha; signal sequence receptor subunit alpha; SSR-alpha (SSR1, TRAPA, PSEC0262)

Function

• subunit of signal sequence receptor whose function is to bind Ca+2 to the ER membrane & thus regulate retention of ER resident proteins
• may be involved in recycling of the translocation apparatus
• may function as a membrane-bound chaperone facilitating folding of translocated proteins
• phosphorylated in its cytoplasmic tail (putative)
• seems to bind Ca+2

Structure

• bipoar molecule:
  • negatively charged N-terminus
  • positively charged C-terminus
• belongs to the TRAP-alpha family

Compartment

• endoplasmic reticulum membrane

Alternative splicing

named isoforms=2

More general terms

• glycoprotein
• membrane protein
• protein subunit
• phosphoprotein

Component of

• endoplasmic reticulum signal sequence receptor (SSR, translocon-associated protein, TRAP)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6745
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6745
• OMIM: https://mirror.omim.org/entry/600868
• UniProt: http://www.uniprot.org/uniprot/P43307.html