Gene and Protein Information
Species	TM	AA	Chromosomal Location	Gene Symbol	Gene Name	Reference
Human	-	724	5q13.1	PIK3R1	phosphoinositide-3-kinase regulatory subunit 1
Mouse	-	724	13 53.92 cM	Pik3r1	phosphoinositide-3-kinase regulatory subunit 1
Rat	-	724	2q12	Pik3r1	phosphoinositide-3-kinase regulatory subunit 1

Previous and Unofficial Names

GRB1 | p50alpha | p55alpha | PI3K regulatory subunit alpha | PI3-kinase regulatory subunit alpha | PtdIns-3-kinase regulatory subunit alpha | phosphoinositide-3-kinase, regulatory subunit 1 (alpha) | phosphatidylinositol 3-kinase, regulatory subunit, polypeptide 1 (p85 alpha)

Database Links
Alphafold	P27986 (Hs), P26450 (Mm), Q63787 (Rn)
CATH/Gene3D	3.30.505.10
ChEMBL Target	CHEMBL2506 (Hs), CHEMBL4106168 (Mm), CHEMBL4106132 (Mm), CHEMBL4106142 (Mm)
Ensembl Gene	ENSG00000145675 (Hs), ENSMUSG00000041417 (Mm), ENSRNOG00000018903 (Rn)
Entrez Gene	5295 (Hs), 18708 (Mm), 25513 (Rn)
Human Protein Atlas	ENSG00000145675 (Hs)
KEGG Gene	hsa:5295 (Hs), mmu:18708 (Mm), rno:25513 (Rn)
OMIM	171833 (Hs)
Pharos	P27986 (Hs)
RefSeq Nucleotide	NM_181523 (Hs), NM_001024955 (Mm), NM_013005 (Rn)
RefSeq Protein	NP_852664 (Hs), NP_001020126 (Mm), NP_037137 (Rn)
UniProtKB	P27986 (Hs), P26450 (Mm), Q63787 (Rn)
Wikipedia	PIK3R1 (Hs)

Immunopharmacology Comments

p85α is included in GtoImmuPdb as it is the regulatory subunit of several PI3Ks (e.g. PI3Kδ and PI3Kγ) with roles in leukocyte biology and therefore important for immunity [3]. Mutations in the PIK3R1 gene that generate proteins incapable of interacting with the catalytic p110 PI3K subunits (and causes elevated p110 activity) are reported to cause human immunodeficiency [2,4].

Immuno Process Associations

Immuno Process:  Inflammation

Immuno Process:  T cell (activation)

Immuno Process:  Immune regulation

Immuno Process:  Chemotaxis & migration

Immuno Process:  Cellular signalling

Immuno Process:  B cell (activation)

Immuno Process:  Immune system development

Immuno Process:  Cytokine production & signalling

Clinically-Relevant Mutations and Pathophysiology

Disease:  Agammaglobulinemia, autosomal recessive Description: A rare form of agammaglobulinemia associated with primary immunodeficiency. Caused by homozygous mutation in the PIK3R1 gene. Synonyms: agammaglobulinemia 7 agammaglobulinemia, non-Bruton type AGM7 OMIM: 615214 Orphanet: ORPHA33110 References:  1,4 Click column headers to sort Type Species Amino acid change Nucleotide change Description Reference Missense Human 301STOP c.901 C>T A novel recessive mutation in exon 7 of the PIK3R1 gene. 4