Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Rho GTPase family of intracellular molecular switches control multiple cellular functions via the regulation of the actin cytoskeleton. Increasing evidence implicates a critical involvement of these molecules in the nervous system, particularly during neuronal migration and polarity, axon and growth cone guidance, dendritic arborization and synaptic formation. However, the molecules regulating Rho GTPase activities in the nervous system are less known. Here, we present the cloning of rat ARHGAP4, a member of the Rho GTPase activating protein family, and also demonstrate its close linkage to the vasopressin 2 receptor gene. In vitro, recombinant ARHGAP4 stimulated the GTPase activity of three members of Rho GTPases, Rac1, Cdc42 and RhoA. ARHGAP4 mRNA expression was observed in multiple tissues with marked expression throughout the developing and adult nervous systems. On closer analysis of protein levels, ARHGAP4 was significantly restricted to specific regions in the nervous system. These included the stratum lucidem in the CA3 area of the hippocampus, neuronal fibers in the ventral region of the brainstem and striatum, and in the cerebellar granule cells. Subcellularly, endogenous ARHGAP4 expression localized to the Golgi complex and could redistribute to the microtubules, for example during mitosis. In addition, distinct protein expression was observed in the tips of differentiating neurites of PC12 cells. Collectively, these results demonstrate that ARHGAP4 is more widely expressed than previously thought but potentially possesses specialized activity in regulating members of the Rho GTPase family in specific cellular compartments of the nervous system.
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PMID:Cloning of rat ARHGAP4/C1, a RhoGAP family member expressed in the nervous system that colocalizes with the Golgi complex and microtubules. 1241 25

We report on an infant boy with congenital hydrocephalus due to L1 syndrome and polyuria due to diabetes insipidus. We initially believed his excessive urine loss was from central diabetes insipidus and that the cerebral malformation caused a secondary insufficient pituitary vasopressin release. However, he failed to respond to treatment with a vasopressin analogue, which pointed to nephrogenic diabetes insipidus (NDI). L1 syndrome and X-linked NDI are distinct clinical disorders caused by mutations in the L1CAM and AVPR2 genes, respectively, located in adjacent positions in Xq28. In this boy we found a deletion of 61,577 basepairs encompassing the entire L1CAM and AVPR2 genes and extending into intron 7 of the ARHGAP4 gene. To our knowledge this is the first description of a patient with a deletion of these three genes. He is the second patient to be described with L1 syndrome and NDI. During follow-up he manifested complications from the hydrocephalus and NDI including global developmental delay and growth failure with low IGF-1 and hypothyroidism.
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PMID:Nephrogenic diabetes insipidus in a patient with L1 syndrome: a new report of a contiguous gene deletion syndrome including L1CAM and AVPR2. 1855 46

Nephrogenic diabetes insipidus (NDI) is a rare disorder of the renal collecting tubules, characterized by an inability to concentrate urine due to an impaired response to arginine vasopressin (AVP), resulting in dilute urine and polyuria. Causes of NDI are heterogeneous and diagnosing congenital NDI (cNDI) in young infants is clinically challenging, as typical symptoms are often unappreciated or inconspicuous. Instead, young infants may present with non-specific signs such as vomiting, poor feeding, failure to thrive, unexplained fevers, irritability, constipation or diarrhea. We report a 37-day-old infant who presented with polyuria and severe hypernatremic dehydration that was unresponsive to vasopressin. The patient was treated with amiloride, indomethacin and hydrochlorothiazide. Genetic analysis revealed a novel contiguous deletion involving the entire AVPR2 gene and the last exon of the adjacent ARHGAP4 gene. A study of the family confirmed the carrier status in the mother. This case illustrates the importance of molecular testing in confirming the diagnosis in the index patient, as well as in identifying asymptomatic at-risk female carriers so that appropriate genetic counselling can be given for reproductive planning. All pediatric patients with suspected cNDI should undergo genetic analysis for a definitive diagnosis.
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PMID:Contiguous gene deletion in a Chinese family with X-linked nephrogenic diabetes insipidus: challenges in early diagnosis and implications for affected families. 3127 58