Disease:Defects in VHL are a cause of pheochromocytoma [MIM:171300]. The pheochromocytomas are catecholamine-producing , chromaffin tumors that arise in the adrenal medulla in 90% of cases. In the remaining 10% of cases , they develop in extra-adrenal sympathetic ganglia and may be referred to as "paraganglioma." Pheochromocytoma usually presents with hypertension. Approximately 10% of pheochromocytoma is hereditary. The genetic basis for most cases of non-syndromic familial pheochromocytoma is unknown. ,Disease:Defects in VHL are a cause of renal cell carcinoma type 1 (RCC1) [MIM:144700]; also called hypernephroma or adenocarcinoma of kidney. Familial renal cell carcinoma syndromes form a group of diseases characterized by a predisposition to development of renal cell carcinomas (RCCs) with various histological subtypes. ,Disease:Defects in VHL are the cause of erythrocytosis familial type 2 (ECYT2) [MIM:263400]; also called VHL-dependent polycythemia or Chuvash type polycythemia. ECYT2 is an autosomal recessive disorder characterized by an increase in serum red blood cell mass , hypersensitivity of erythroid progenitors to erythropoietin , increased erythropoietin serum levels , and normal oxygen affinity. Patients with ECYT2 carry a high risk for peripheral thrombosis and cerebrovascular events. ,Disease:Defects in VHL are the cause of von Hippel-Lindau disease (VHLD) [MIM:193300]. VHLD is a dominantly inherited familial cancer syndrome characterized by the development of retinal angiomatosis , cerebellar and spinal hemangioblastoma , renal cell carcinoma (RCC) , phaeochromocytoma and pancreatic tumors. VHL type 1 is without pheochromocytoma , type 2 is with pheochromocytoma. VHL type 2 is further subdivided into types 2A (pheochromocytoma , retinal angioma , and hemangioblastomas without renal cell carcinoma and pancreatic cyst) and 2B (pheochromocytoma , retinal angioma , and hemangioblastomas with renal cell carcinoma and pancreatic cyst) . VHL type 2C refers to patients with isolated pheochromocytoma without hemangioblastoma or renal cell carcinoma. The estimated incidence is 3/100000 births per year and penetrance is 97% by age 60 years. ,Domain:The elongin BC complex binding domain is also known as BC-box with the consensus [APST]-L-x (3) -C-x (3) -[AILV]. ,Function:Involved in the ubiquitination and subsequent proteasomal degradation via the von Hippel-Lindau ubiquitination complex. Seems to act as target recruitment subunit in the E3 ubiquitin ligase complex and recruits hydroxylated hypoxia-inducible factor (HIF) under normoxic conditions. Involved in transcriptional repression through interaction with HIF1A , HIF1AN and histone deacetylases. ,pathway:Protein modification; protein ubiquitination. ,subcellular location:Equally distributed between the nucleus and the cytoplasm but not membrane-associated. ,subcellular location:Found predominantly in the cytoplasm and with less amounts nuclear or membrane-associated. ,subunit:Component of the VCB (VHL-Elongin BC-CUL2) complex; this complex acts as a ubiquitin-ligase E3 and directs proteosome-dependent degradation of targeted proteins. Interacts with CUL2; this interaction is dependent on the integrity of the trimeric VBC complex. Interacts (via the beta domain) with HIF1A (via the NTAD domain) ; this interaction mediates degradation of HIF1A in normoxia and , in hypoxia , prevents ubiqitination and degradation of HIF1A by mediating hypoxia-induced translocation to the nucleus , a process which requires a hypoxia-dependent regulatory signal. Interacts with RNF139 and UBP33. Interacts with PHF17. ,tissue specificity:Expressed in the adult and fetal brain and kidney. ,
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