MYOC

MYOC encodes the protein myocilin, which is believed to have a role in cytoskeletal function. MYOC is expressed in many occular 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. [provided by RefSeq, Jul 2008]

Myocilin

Secreted glycoprotein regulating the activation of different signaling pathways in adjacent cells to control different processes including cell adhesion, cell-matrix adhesion, cytoskeleton organization and cell migration. Promotes substrate adhesion, spreading and formation of focal contacts. Negatively regulates cell-matrix adhesion and stress fiber assembly through Rho protein signal transduction. Modulates the organization of actin cytoskeleton by stimulating the formation of stress fibers through interactions with components of Wnt signaling pathways. Promotes cell migration through activation of PTK2 and the downstream phosphatidylinositol 3-kinase signaling. Plays a role in bone formation and promotes osteoblast differentiation in a dose-dependent manner through mitogen-activated protein kinase signaling. Mediates myelination in the peripheral nervous system through ERBB2/ERBB3 signaling. Plays a role as a regulator of muscle hypertrophy through the components of dystrophin-associated protein complex. Involved in positive regulation of mitochondrial depolarization. Plays a role in neurite outgrowth. May participate in the obstruction of fluid outflow in the trabecular meshwork.

Bone development Source: UniProtKB
Clustering of voltage-gated sodium channels Source: UniProtKB
ERBB2-ERBB3 signaling pathway Source: UniProtKB
Myelination in peripheral nervous system Source: UniProtKB
Negative regulation of cell-matrix adhesion Source: UniProtKB
Negative regulation of Rho protein signal transduction Source: UniProtKB
Negative regulation of stress fiber assembly Source: UniProtKB
Neuron projection development Source: UniProtKB
Non-canonical Wnt signaling pathway via JNK cascade Source: UniProtKB
Osteoblast differentiation Source: UniProtKB
Positive regulation of cell migration Source: UniProtKB
Positive regulation of focal adhesion assembly Source: UniProtKB
Positive regulation of mitochondrial depolarization Source: UniProtKB
Positive regulation of phosphatidylinositol 3-kinase signaling Source: UniProtKB
Positive regulation of protein kinase B signaling Source: UniProtKB
Positive regulation of stress fiber assembly Source: UniProtKB
Positive regulation of substrate adhesion-dependent cell spreading Source: UniProtKB
Regulation of MAPK cascade Source: UniProtKB
Signal transduction Source: GO_Central
Skeletal muscle hypertrophy Source: UniProtKB

Secreted
extracellular space
extracellular matrix
extracellular exosome
Golgi apparatus
Endoplasmic reticulum
Rough endoplasmic reticulum
Mitochondrion
Mitochondrion intermembrane space
Mitochondrion inner membrane
Mitochondrion outer membrane
Other locations
Cytoplasmic vesicle
Cell projection
cilium
Note: Located preferentially in the ciliary rootlet and basal body of the connecting cilium of photoreceptor cells, and in the rough endoplasmic reticulum (PubMed:9169133). It is only imported to mitochondria in the trabecular meshwork (PubMed:17516541). Localizes to the Golgi apparatus in Schlemm's canal endothelial cells (PubMed:11053284). Appears in the extracellular space of trabecular meshwork cells by an unconventional mechanism, likely associated with exosome-like vesicles (PubMed:15944158). Localizes in trabecular meshwork extracellular matrix (PubMed:15944158).
Myocilin, C-terminal fragment:
Secreted
Myocilin, N-terminal fragment:
Endoplasmic reticulum
Note: Remains retained in the endoplasmic reticulum.

Glaucoma 1, open angle, A (GLC1A):
A form of primary open angle glaucoma (POAG). POAG is characterized by a specific pattern of optic nerve and visual field defects. The angle of the anterior chamber of the eye is open, and usually the intraocular pressure is increased. However, glaucoma can occur at any intraocular pressure. The disease is generally asymptomatic until the late stages, by which time significant and irreversible optic nerve damage has already taken place.

Different isoforms may arise by post-translational modifications.
Glycosylated.
Palmitoylated.
Undergoes a calcium-dependent proteolytic cleavage at Arg-226 by CAPN2 in the endoplasmic reticulum. The result is the production of two fragments, one of 35 kDa containing the C-terminal olfactomedin-like domain, and another of 20 kDa containing the N-terminal leucine zipper-like domain.