From Wikipedia, the free encyclopedia
Jump to: navigation, search
Adaptor-related protein complex 4, sigma 1 subunit
Symbols AP4S1 ; AP47B; CLA20; CLAPS4; CPSQ6; SPG52
External IDs OMIM607243 MGI1337065 HomoloGene32513 GeneCards: AP4S1 Gene
Species Human Mouse
Entrez 11154 11782
Ensembl ENSG00000100478 ENSMUSG00000020955
UniProt Q9Y587 Q9WVL1
RefSeq (mRNA) NM_001128126 NM_021710
RefSeq (protein) NP_001121598 NP_068356
Location (UCSC) Chr 14:
31.03 – 31.1 Mb
Chr 12:
51.69 – 51.74 Mb
PubMed search [1] [2]

AP-4 complex subunit sigma-1 is a protein that in humans is encoded by the AP4S1 gene.[1]


The heterotetrameric adaptor protein (AP) complexes sort integral membrane proteins at various stages of the endocytic and secretory pathways. AP4 is composed of 2 large chains, beta-4 (AP4B1) and epsilon-4 (AP4E1), a medium chain, mu-4 (AP4M1), and a small chain, sigma-4 (AP4S1, this gene).[1]

Clinical relevance[edit]

It is currently hypothesized that AP4-complex-mediated trafficking plays a crucial role in brain development and functioning.[2]


  1. ^ a b "Entrez Gene: adaptor-related protein complex 4". 
  2. ^ Abou Jamra R, Philippe O, Raas-Rothschild A, Eck SH, Graf E, Buchert R, Borck G, Ekici A, Brockschmidt FF, Nöthen MM, Munnich A, Strom TM, Reis A, Colleaux L (May 2011). "Adaptor Protein Complex 4 Deficiency Causes Severe Autosomal-Recessive Intellectual Disability, Progressive Spastic Paraplegia, Shy Character, and Short Stature". Am J Hum Genet 88 (6): 788–95. doi:10.1016/j.ajhg.2011.04.019. PMC 3113253. PMID 21620353. 

Further reading[edit]