Golgi reassembly-stacking protein 1; Golgi peripheral membrane protein p65; Golgi phosphoprotein 5; GOLPH5; Golgi reassembly-stacking protein of 65 kDa; GRASP65 (GORASP1, GOLPH5, GRASP65)

Function

• stacking factor involved in the postmitotic assembly of Golgi stacks from mitotic Golgi fragments
• key structural protein required for maintenance of Golgi integrity
  • its caspase-mediated cleavage is required for fragmentation of the Golgi during apoptosis
• mediates, via its interaction with GM130, docking of transport vesicles with Golgi membranes
• phosphorylated by CDC2/cyclin B1 & PLK kinases during mitosis
• phosphorylation cycle correlates with the cisternal stacking cycle
• phosphorylation of the homodimer prevents association of dimers into higher order oligomers, leading to cisternal unstacking
• target for caspase-3 cleavage during apoptosis
  • cleavage contributes to Golgi fragmentation & occurs very early in the execution phase of apoptosis (putative)
• homodimer
  • forms higher order oligomers during interphase
  • does not form higher order oligomers during mitosis
  • dimers of the protein on one membrane might be able to interact with dimers on another & so stack cisternae
• interacts with the C-terminus of GM130 (mitosis-independent)
  • role in targeting of both proteins to the cis-Golgi
• the GORASP1/GM130 complex binds to vesicle docking protein p115
• interacts with TMED2 & TMED3 (putative)

Structure

• belongs to the GORASP family
• contains 1 PDZ domain (DHR domain)

Compartment

• Golgi, cis-Golgi network membrane
• peripheral membrane; cytoplasmic side
• undergoes rapid exchange with the cytosol

Alternative splicing

named isoforms=3

More general terms

• Golgi reassembly stacking protein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=64689
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:64689
• OMIM: https://mirror.omim.org/entry/606867
• UniProt: http://www.uniprot.org/uniprot/Q9BQQ3.html