Colipase

Colipase, abbreviated CLPS, is a protein co-enzyme that counteracts the inhibitory effect of intestinal bile acid on the enzymatic activity of pancreatic lipase. It is secreted by the pancreas in an inactive form, procolipase, which is activated in the intestinal lumen by trypsin.

CLPS
Identifiers
Aliases	CLPS, entrez:1208, colipase
External IDs	OMIM: 120105; MGI: 88421; HomoloGene: 1383; GeneCards: CLPS; OMA:CLPS - orthologs
Gene location (Human) Chr. Chromosome 6 (human)[1] Band 6p21.31 Start 35,794,982 bp[1] End 35,797,344 bp[1]
Gene location (Mouse) Chr. Chromosome 17 (mouse)[2] Band 17|17 A3.3 Start 28,777,123 bp[2] End 28,779,740 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in body of pancreas islet of Langerhans testicle pancreatic epithelial cell beta cell right coronary artery ectocervix right uterine tube Descending thoracic aorta right lobe of liver Top expressed in stomach islet of Langerhans jejunum duodenum colon ileum esophagus morula quadriceps femoris muscle yolk sac More reference expression data BioGPS More reference expression data
Gene ontology Molecular function enzyme activator activity Cellular component extracellular region Biological process lipid catabolic process digestion positive regulation of catalytic activity lipid metabolism response to food response to bacterium retinoid metabolic process lipid digestion Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 1208 109791 Ensembl ENSG00000137392 ENSMUSG00000024225 UniProt P04118 Q9CQC2 RefSeq (mRNA) NM_001832 NM_001252597 NM_001252598 NM_025469 NM_001317065 RefSeq (protein) NP_001239526 NP_001239527 NP_001823 NP_001303994 NP_079745 Location (UCSC) Chr 6: 35.79 – 35.8 Mb Chr 17: 28.78 – 28.78 Mb PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse

Intestinal bile acids (which aid lipid digestion by facilitating micelle formation) adhere to the surface of emulsified fat droplets, displacing lipase (which is only active at the water-fat interface) from the droplet surface. Colipase acts as a bridging molecule, binding to both lipase and bile acids, thus anchoring lipase onto the droplet surface, preventing its displacement.^[5]

In humans, the colipase protein is encoded by the CLPS gene.^[6]

Protein domain

Colipase is also a family of evolutionarily related proteins.

Colipase is a small protein cofactor needed by pancreatic lipase for efficient dietary lipid hydrolysis. Efficient absorption of dietary fats is dependent on the action of pancreatic triglyceride lipase. Colipase binds to the C-terminal, non-catalytic domain of lipase, thereby stabilising an active conformation and considerably increasing the hydrophobicity of its binding site. Structural studies of the complex and of colipase alone have revealed the functionality of its architecture.^[7][8]

Colipase is a small protein (12K) with five conserved disulphide bonds. Structural analogies have been recognised between a developmental protein (Dickkopf), the pancreatic lipase C-terminal domain, the N-terminal domains of lipoxygenases and the C-terminal domain of alpha-toxin. These non-catalytic domains in the latter enzymes are important for interaction with membrane. It has not been established if these domains are also involved in eventual protein cofactor binding as is the case for pancreatic lipase.^[8]

Colipase N-terminal domain Structure of the pancreatic lipase-colipase complex inhibited by a C11 alkyl phosphonate.[9] Identifiers Symbol Colipase Pfam PF01114 InterPro IPR001981 PROSITE PDOC00111 SCOP2 1lpb / SCOPe / SUPFAM CDD cd00039 Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary PDB 1eth​, 1lpa​, 1lpb​, 1n8s​, 1pcn​, 1pco​

Colipase C-terminal domain
solution structure of porcine pancreatic procolipase as determined from 1h homonuclear two-and three-dimensional nmr
Identifiers
Symbol	Colipase_C
Pfam	PF02740
InterPro	IPR017914
PROSITE	PDOC00111
SCOP2	1lpb / SCOPe / SUPFAM
CDD	cd00039
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

See also

• Enterostatin