signal-induced proliferation-associated 1 like protein 1; SIPA1-like protein 1; high-risk human papilloma viruses E6 oncoproteins targeted protein 1; E6-targeted protein 1 (SIPA1L1, E6TP1, KIAA0440)

Function

• stimulates the GTPase activity of RAP2A
• promotes reorganization of the actin cytoskeleton & recruits DLG4 to F-actin
• contributes to the regulation of dendritic spine morphogenesis (putative)
• ubiquitinated & degraded by the SCF(BTRC) following phosphorylation by PLK2 (putative)
• phosphorylated at Ser-1349 by CDK5, creating a docking site for the POLO box domains of PLK2. subsequently, PLK2 binds & phosphorylates SIPA1L1, leading to ubiquitination & degradation by the proteasome (putative)
• interacts with DLG4, PDLIM5, PDLIM7 & PROSAPIP1
• interacts with the actin cytoskeleton (putative)
• interacts (via PDZ domain) with EPHA4 (via PDZ motif); controls neuronal morphology through regulation of RAP1 (RAP1A or RAP1B) & RAP2 (RAP2A, RAP2B or RAP2C) GTPases
• interacts with HPV E6

Structure

• contains 1 PDZ domain (DHR domain)
  • contains 1 rap-GAP domain

Compartment

• cytoplasm, cytoskeleton (putative)
• cell junction, synapse, postsynaptic cell membrane, postsynaptic density (putative)
• cell junction, synapse, synaptosome
• associated with the actin cytoskeleton
• detected at synapses & dendritic spines of cultured hippocampal neurons

Alternative splicing

named isoforms=2

Expression

widely expressed

More general terms

• rap GTPase-activating protein (rap-GAP)
• phosphoprotein

Additional terms

• papillomavirus
• papillomavirus oncoprotein E6
• signal-induced proliferation-associated protein 1; Sipa-1; GTPase-activating protein Spa-1; p130 SPA-1 (SIPA1, SPA1)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=26037
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:26037
• UniProt: http://www.uniprot.org/uniprot/O43166.html