UniProt functional annotation for Q13231



	UniProt functional annotation for Q13231

UniProt code: Q13231.

Organism: Homo sapiens (Human).

Taxonomy: Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.

Function: Degrades chitin, chitotriose and chitobiose. May participate in the defense against nematodes and other pathogens. Isoform 3 has no enzymatic activity. {ECO:0000269|PubMed:7592832, ECO:0000269|PubMed:7836450}.

Catalytic activity: Reaction=Random endo-hydrolysis of N-acetyl-beta-D-glucosaminide (1->4)-beta-linkages in chitin and chitodextrins.; EC=3.2.1.14; Evidence={ECO:0000269|PubMed:15664516, ECO:0000269|PubMed:19725875, ECO:0000269|PubMed:7836450};

Subunit: Monomer. {ECO:0000269|PubMed:11960986, ECO:0000269|PubMed:12639956, ECO:0000269|PubMed:15664516}.

Subcellular location: Secreted. Lysosome. Note=A small proportion is lysosomal.

Tissue specificity: Detected in spleen. Secreted by cultured macrophages. {ECO:0000269|PubMed:7836450}.

Polymorphism: A 24 bp duplication in exon 10 leads to the activation of an alternative splice site and the production of an inactive protein resulting in chitotriosidase deficiency [MIM:614122]. About 6% of the population are deficient for CHIT1 activity, while 35% are carriers and show reduced enzyme levels. People with CHIT1 deficiency appear perfectly healthy. {ECO:0000269|PubMed:9748235}.

Miscellaneous: Very high plasma levels of CHIT1 are found in patients with Gaucher disease type 1 (GD I). Can be used as diagnostic aid and to evaluate the success of treatment that brings levels back to normal.

Miscellaneous: [Isoform 3]: Duplication of 24 bp in exon 10 leads to the use of a cryptic splice site. The normal splice site is still present but not used. {ECO:0000305}.

Similarity: Belongs to the glycosyl hydrolase 18 family. Chitinase class II subfamily. {ECO:0000305}.

Sequence caution: Sequence=BAG51478.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305};

Annotations taken from UniProtKB at the EBI.


Organism:		Homo sapiens (Human).
Taxonomy:		Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo.



Function:		Degrades chitin, chitotriose and chitobiose. May participate in the defense against nematodes and other pathogens. Isoform 3 has no enzymatic activity. {ECO:0000269\|PubMed:7592832, ECO:0000269\|PubMed:7836450}.


Catalytic activity:		Reaction=Random endo-hydrolysis of N-acetyl-beta-D-glucosaminide (1->4)-beta-linkages in chitin and chitodextrins.; EC=3.2.1.14; Evidence={ECO:0000269\|PubMed:15664516, ECO:0000269\|PubMed:19725875, ECO:0000269\|PubMed:7836450};
Subunit:		Monomer. {ECO:0000269\|PubMed:11960986, ECO:0000269\|PubMed:12639956, ECO:0000269\|PubMed:15664516}.
Subcellular location:		Secreted. Lysosome. Note=A small proportion is lysosomal.
Tissue specificity:		Detected in spleen. Secreted by cultured macrophages. {ECO:0000269\|PubMed:7836450}.
Polymorphism:		A 24 bp duplication in exon 10 leads to the activation of an alternative splice site and the production of an inactive protein resulting in chitotriosidase deficiency [MIM:614122]. About 6% of the population are deficient for CHIT1 activity, while 35% are carriers and show reduced enzyme levels. People with CHIT1 deficiency appear perfectly healthy. {ECO:0000269\|PubMed:9748235}.
Miscellaneous:		Very high plasma levels of CHIT1 are found in patients with Gaucher disease type 1 (GD I). Can be used as diagnostic aid and to evaluate the success of treatment that brings levels back to normal.
Miscellaneous:		[Isoform 3]: Duplication of 24 bp in exon 10 leads to the use of a cryptic splice site. The normal splice site is still present but not used. {ECO:0000305}.
Similarity:		Belongs to the glycosyl hydrolase 18 family. Chitinase class II subfamily. {ECO:0000305}.
Sequence caution:		Sequence=BAG51478.1; Type=Erroneous initiation; Note=Extended N-terminus.; Evidence={ECO:0000305};