NRAS
This is an N-ras oncogene encoding a membrane protein that shuttles between the Golgi apparatus and the plasma membrane. This shuttling is regulated through palmitoylation and depalmitoylation by the ZDHHC9-GOLGA7 complex. The encoded protein, which has intrinsic GTPase activity, is activated by a guanine nucleotide-exchange factor and inactivated by a GTPase activating protein. Mutations in this gene have been associated with somatic rectal cancer, follicular thyroid cancer, autoimmune lymphoproliferative syndrome, Noonan syndrome, and juvenile myelomonocytic leukemia.
Involvement in disease
Leukemia, juvenile myelomonocytic (JMML):
An aggressive pediatric myelodysplastic syndrome/myeloproliferative disorder characterized by malignant transformation in the hematopoietic stem cell compartment with proliferation of differentiated progeny. Patients have splenomegaly, enlarged lymph nodes, rashes, and hemorrhages.
Noonan syndrome 6 (NS6):
A form of Noonan syndrome, a disease characterized by short stature, facial dysmorphic features such as hypertelorism, a downward eyeslant and low-set posteriorly rotated ears, and a high incidence of congenital heart defects and hypertrophic cardiomyopathy. Other features can include a short neck with webbing or redundancy of skin, deafness, motor delay, variable intellectual deficits, multiple skeletal defects, cryptorchidism, and bleeding diathesis. Individuals with Noonan syndrome are at risk of juvenile myelomonocytic leukemia, a myeloproliferative disorder characterized by excessive production of myelomonocytic cells.
RAS-associated autoimmune leukoproliferative disorder (RALD):
A disorder of apoptosis, characterized by chronic accumulation of non-malignant lymphocytes, defective lymphocyte apoptosis, and an increased risk for the development of hematologic malignancies.
Melanocytic nevus syndrome, congenital (CMNS):
A syndrome characterized by congenital pigmentary skin lesions which can occur at any site and can cover most of the body surface. These lesions may or may not be hairy. Congenital melanocytic nevi are associated with neuromelanosis (the presence of melanin-producing cells within the brain parenchyma or leptomeninges). Less commonly they are associated with malignant melanoma in childhood, both in the skin and the central nervous system. CMNS patients also tend to have a characteristic facial appearance, including wide or prominent forehead, periorbital fullness, small short nose with narrow nasal bridge, round face, full cheeks, prominent premaxilla, and everted lower lip.
Melanosis, neurocutaneous (NCMS):
A rare congenital disease characterized by the presence of giant or multiple melanocytic nevi on the skin, foci of melanin-producing cells within the brain parenchyma, and infiltration of leptomeninges by abnormal melanin deposits. Neurologic abnormalities include seizures, hydrocephalus, arachnoid cysts, tumors, and syringomyelia. Some patients may develop malignant melanoma.
Keratinocytic non-epidermolytic nevus (KNEN):
Epidermal nevi of the common, non-organoid and non-epidermolytic type are benign skin lesions and may vary in their extent from a single (usually linear) lesion to widespread and systematized involvement. They may be present at birth or develop early during childhood.
Thyroid cancer, non-medullary, 2 (NMTC2):
A form of non-medullary thyroid cancer (NMTC), a cancer characterized by tumors originating from the thyroid follicular cells. NMTCs represent approximately 95% of all cases of thyroid cancer and are classified into papillary, follicular, Hurthle cell, and anaplastic neoplasms.
PTM
Palmitoylated by the ZDHHC9-GOLGA7 complex (PubMed:16000296).
Depalmitoylated by ABHD17A, ABHD17B and ABHD17C (PubMed:26701913).
A continuous cycle of de- and re-palmitoylation regulates rapid exchange between plasma membrane and Golgi (PubMed:16000296, PubMed:15705808, PubMed:2661017, PubMed:26701913).
Acetylation at Lys-104 prevents interaction with guanine nucleotide exchange factors (GEFs).
Fatty-acylated at Lys-169 and/or Lys-170.
Ubiquitinated by the BCR(LZTR1) E3 ubiquitin ligase complex at Lys-170 in a non-degradative manner, leading to inhibit Ras signaling by decreasing Ras association with membranes.
Phosphorylation at Ser-89 by STK19 enhances NRAS-association with its downstream effectors.
(Microbial infection) Glucosylated at Thr-35 by P.sordellii toxin TcsL.