Myocilin

MYOC
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 4WXQ, 4WXS, 4WXU
Identifiers
Aliases	MYOC, GLC1A, GPOA, JOAG, JOAG1, TIGR, myocilin
External IDs	MGI: 1202864 HomoloGene: 220 GeneCards: MYOC
Gene ontology Molecular function • frizzled binding • receptor tyrosine kinase binding • myosin light chain binding • protein binding • fibronectin binding • metal ion binding Cellular component • mitochondrial outer membrane • cytoplasmic vesicle • rough endoplasmic reticulum • node of Ranvier • mitochondrial intermembrane space • cell projection • cytoplasmic, membrane-bounded vesicle • extracellular exosome • membrane • endoplasmic reticulum • extracellular matrix • Golgi apparatus • proteinaceous extracellular matrix • extracellular region • mitochondrion • cilium • extracellular fluid • mitochondrial inner membrane Biological process • non-canonical Wnt signaling pathway via JNK cascade • regulation of cell-matrix adhesion • positive regulation of substrate adhesion-dependent cell spreading • myelination in peripheral nervous system • negative regulation of stress fiber assembly • positive regulation of focal adhesion assembly • positive regulation of phosphatidylinositol 3-kinase signaling • positive regulation of mitochondrial depolarization • ERBB2-ERBB3 signaling pathway • positive regulation of stress fiber assembly • clustering of voltage-gated sodium channels • bone development • positive regulation of cell migration • regulation of stress fiber assembly • negative regulation of Rho protein signal transduction • osteoblast differentiation • positive regulation of protein kinase B signaling • skeletal muscle hypertrophy • neuron projection development • regulation of MAPK cascade • negative regulation of cell-matrix adhesion Sources:Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	4653	17926
Ensembl	ENSG00000034971	ENSMUSG00000026697
UniProt	Q99972	O70624
RefSeq (mRNA)	NM_000261	NM_010865
RefSeq (protein)	NP_000252.1	NP_034995.3
Location (UCSC)	Chr 1: 171.64 – 171.65 Mb	Chr 1: 162.64 – 162.65 Mb
PubMed search	[1]	[2]
Wikidata

Myocilin, trabecular meshwork inducible glucocorticoid response, also known as MYOC, is a protein which in humans is encoded by the MYOC gene.^[3][4] Mutations in MYOC are a major cause of glaucoma.

Function

MYOC encodes the protein myocilin. The precise function of myocilin is unknown, but it is normally secreted into the aqueous humor of the eye. MYOC mutations, which cause myocilin to accumulate in the cells of the trabecular meshwork are a common cause of glaucoma.

Myocilin is believed to have a role in cytoskeletal function. MYOC is expressed in many ocular tissues, including the trabecular meshwork, and was revealed to be the trabecular meshwork glucocorticoid-inducible response protein (TIGR). The trabecular meshwork is a specialized eye tissue essential in regulating intraocular pressure, and mutations in MYOC have been identified as the cause of hereditary juvenile-onset open-angle glaucoma.^[5]

Clinical significance

MYOC contains a signal sequence for secretion, and is secreted into the aqueous humor of the eye by the trabecular meshwork. Mutations in MYOC are found in 4% of adult-onset primary open-angle glaucoma and >10% of juvenile-onset primary open-angle glaucoma. Overexpression or underexpression of MYOC does not cause glaucoma. However, the MYOC gene also contains a signal sequence, which is normally not functional, that directs intracellular proteins to peroxisomes. Glaucoma-associated mutations activate that signal sequence and direct myocilin to peroxisomes, where they accumulate in the cell, instead of being secreted. Decreased secretion and increased accumulation appear to be the initial steps in myocilin-associated glaucoma.^[6]

Interactions

MYOC has been shown to interact with OLFM3.^[7]

References

Further reading