The PRPS1 gene encodes phosphoribosyl pyrophosphate synthetase 1 (PRS-1). The phenotypes associated with PRPS1 mutations include DFN2 (mild PRS-1 deficiency), CMTX5 (moderate PRS-1 deficiency), Arts ...syndrome (severe PRS-1 deficiency), and PRS-1 superactivity1. X-linked Charcot-Marie-Tooth disease type 5 (CMTX5) is a very rare hereditary neuropathy characterized by deafness, optic atrophy, and polyneuropathy. We herein report a Japanese patient with CMTX5 who had a novel hemizygous mutation c.82 G>C in PRPS1. Despite showing a typical clinical picture, the decrease in enzyme activity measured in the patient's erythrocytes was milder than in previously reported cases.
Abstract
Objectives
Phosphoribosylpyrophosphate synthetase (PRPS1) superactivity is an X-linked disorder characterized by urate overproduction Online Mendelian Inheritance in Man (OMIM) gene ...reference 300661. This condition is thought to rarely affect women, and when it does, the clinical presentation is mild. We describe a 16-year-old African American female who developed progressive tophi, nephrolithiasis and acute kidney failure due to urate overproduction. Family history included a mother with tophaceous gout who developed end-stage kidney disease due to nephrolithiasis and an affected sister with polyarticular gout. The main aim of this study was to describe the clinical manifestations of PRPS1 superactivity in women.
Methods
Whole exome sequencing was performed in affected females and their fathers.
Results
Mutational analysis revealed a new c.520 G > A (p.G174R) mutation in the PRPS1 gene. The mutation resulted in decreased PRPS1 inhibition by ADP.
Conclusion
Clinical findings in previously reported females with PRPS1 superactivity showed a high clinical penetrance of this disorder with a mean serum urate level of 8.5 (4.1) mg/dl 506 (247) μmol/l and a high prevalence of gout. These findings indicate that all women in families with PRPS1 superactivity should be genetically screened for a mutation (for clinical management and genetic counselling). In addition, women with tophaceous gout, gout presenting in childhood, or a strong family history of severe gout should be considered for PRPS1 mutational analysis.
Disorders of purine biosynthesis metabolism Dewulf, Joseph P.; Marie, Sandrine; Nassogne, Marie-Cécile
Molecular genetics and metabolism,
07/2022, Letnik:
136, Številka:
3
Journal Article
Recenzirano
Purines are essential molecules that are components of vital biomolecules, such as nucleic acids, coenzymes, signaling molecules, as well as energy transfer molecules. The de novo biosynthesis ...pathway starts from phosphoribosylpyrophosphate (PRPP) and eventually leads to the synthesis of inosine monophosphate (IMP) by means of 10 sequential steps catalyzed by six different enzymes, three of which are bi-or tri-functional in nature. IMP is then converted into guanosine monophosphate (GMP) or adenosine monophosphate (AMP), which are further phosphorylated into nucleoside di- or tri-phosphates, such as GDP, GTP, ADP and ATP. This review provides an overview of inborn errors of metabolism pertaining to purine synthesis in humans, including either phosphoribosylpyrophosphate synthetase (PRS) overactivity or deficiency, as well as adenylosuccinate lyase (ADSL), 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase (ATIC), phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), and adenylosuccinate synthetase (ADSS) deficiencies. ITPase deficiency is being described as well. The clinical spectrum of these disorders is broad, including neurological impairment, such as psychomotor retardation, epilepsy, hypotonia, or microcephaly; sensory involvement, such as deafness and visual disturbances; multiple malformations, as well as muscle presentations or consequences of hyperuricemia, such as gouty arthritis or kidney stones. Clinical signs are often nonspecific and, thus, overlooked. It is to be hoped that this is likely to be gradually overcome by using sensitive biochemical investigations and next-generation sequencing technologies.
Phosphoribosyl pyrophosphate synthetase 1 (PRPS1) is the first enzyme in the
de novo
purine nucleotide synthesis pathway and is essential for cell development. However, the effect of PRPS1 on ...melanoma proliferation and metastasis remains unclear. This study aimed to investigate the regulatory mechanism of PRPS1 in the malignant progression of melanoma. Here, we found PRPS1 was upregulated in melanoma and melanoma cells. In addition, our data indicated that PRPS1 could promote the proliferation and migration and invasion of melanoma both
in vitro
and
in vivo
. PRPS1 also could inhibit melanoma cell apoptosis. Furthermore, we found NRF2 is an upstream transcription factor of PRPS1 that drive malignant progression of melanoma.
Growing evidences suggest that long non-coding RNAs (lncRNAs) are closely correlated to the development of human cancer, such as colorectal cancer (CRC). A previous report suggested that DLEU1 ...accelerated CRC development. However, DLEU1’s underlying mechanism in CRC remains unclear. In our study, the level of DLEU1 in CRC tissues is investigated by qRT-PCR. Our data exhibited that DLEU1 level was observably increased in CRC tissues and CRC cell lines and was closely associated with bad prognosis of CRC patients. CRC cell proliferation was repressed by sh-LncRNA DLEU1, whereas cell apoptosis was markedly stimulated. Moreover, knockdown of DLEU1 inhibited cell migration and invasion. Mechanistically, through interacting with miR-320b in CRC, DLEU1 promoted the level of PRPS1 which was a target of miR-320b. The rescue experiment confirmed that knockdown of DLEU1 repressed cell proliferation, migration and invasion while stimulated cell apoptosis via miR-320b/phosphoribosyl pyrophosphate synthetase 1 (PRPS1) axis. Meanwhile, the data of xenograft model exhibited that inhibition of DLEU1 suppressed tumor growth
in vivo
. In summary, DLEU1 knockdown may repress PRPS1 expression via miR-320b, and then repress cell proliferation, migration and invasion while stimulate cell apoptosis. Our research may provide a novel target for the treatment of CRC.
This study describes how the diagnosis of Usher syndrome was revised to PRPS1-associated retinopathy and Charcot-Marie-Tooth disease type 5.
A 38-year-old female with bilaterally subnormal vision and ...non-congenital hearing loss was initially diagnosed with Usher syndrome, based on finding variants in three genes (MYO7A, USH2A, and PCDH15), was re-evaluated at the inherited retinal disorders clinic. She had asymmetric retinopathy and right macular pseudocoloboma. She was also found to have myopathic facies, poor grip strength and atrophy of the calf muscles. Whole exome sequencing including variants in PRPS1 showed a variant (NM_002764.4:c.287 G > A; p.Arg96Gln), which was not detected by targeted Sanger sequencing of the DNA from her mother and sister.
The constellation of asymmetric retinopathy and non-congenital hearing impairment should prompt the clinician to search for other diagnoses that may not be covered by an Usher syndrome next generation sequencing panel. Interpretation of genetic testing results should be correlated with a detailed clinical phenotype.
Objective·To study whether mutations at the I72 site of phosphoribosyl pyrophosphate synthetase 1 (PRPS1) can induce resistance in acute lymphoblastic leukemia (ALL) cells to thiopurine chemotherapy ...drugs 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG), and explain their mechanisms of action.Methods·The PRPS1 gene mutations (I72F, R177S and V316L) found in clinical practice and PRPS1 gene mutations (V208A and V289A) present in two ALL cell lines (KOPN72bi and RS4;11) were constructed into the vector pGV303 fused with green fluorescent protein (GFP), respectively. The PRPS1 A190T mutation that has been proven to be resistant to thiopurine chemotherapy drugs was used as the positive control, and the empty vector pGV303 (Vector), PRPS1 wild-type (WT) and PRPS1 I72V were used as the negative controls. The various mutants of PRPS1 were transiently transfected into HEK-293T cells (referred to as 293T cells), and the expression of these exogenous PRPS1 was detected by Western blotting. The half maximal inhibitory c
Phosphoribosyl pyrophosphate synthetases (EC 2.7.6.1) are key enzymes in the biological synthesis of phosphoribosyl pyrophosphate and are involved in diverse developmental processes. In our previous ...study, the PRPS1 gene was discovered as a key disease-resistance candidate gene in yellow drum, Nibea albiflora, in response to the infection of Vibrio harveyi, through genome-wide association analysis. This study mainly focused on the characteristics and its roles in immune responses of the PRPS1 gene in yellow drum. In the present study, the NaPRPS1 gene was cloned from yellow drum, encoding a protein of 320 amino acids. Bioinformatic analysis showed that NaPRPS1 was highly conserved during evolution. Quantitative RT-PCR demonstrated that NaPRPS1 was highly expressed in the head-kidney and brain, and its transcription and translation were significantly activated by V. harveyi infection examined by RT-qPCR and immunohistochemistry analysis, respectively. Subcellular localization revealed that NaPRPS1 was localized in cytoplasm. In addition, semi-in vivo pull-down assay coupled with mass spectrometry identified myeloid differentiation factor 88 (MyD88) as an NaPRPS1-interacting patterner, and their interaction was further supported by reciprocal pull-down assay and co-immunoprecipitation. The inducible expression of MyD88 by V. harveyi suggested that the linker molecule MyD88 in innate immune response may play together with NaPRPS1 to coordinate the immune signaling in yellow drum in response to the pathogenic infection. We provide new insights into important functions of PRPS1, especially PRPS1 in the innate immunity of teleost fishes, which will benefit the development of marine fish aquaculture.
X‐linked Charcot‐Marie‐Tooth disease‐5 (CMTX5) is a rare hereditary disorder caused by mutations in the gene for phosphoribosyl pyrophosphate synthetase‐1 (PRPS1). We investigated a boy with a novel ...PRPS1 mutation (c.334G>C, p.V112L) via genetic, neuropathological and enzymatic tests. The proband was a 13‐year‐old boy with congenital non‐syndromic sensorineural deafness. At 3 year old, he developed progressive distal weakness of all limbs with muscle atrophy of both hands and shanks. Nerve conduction study revealed the loss of sensory nerve action potentials, and slowing down of motor nerve conduction velocities with a decrease of amplitudes of compound motor action potentials. Visual evoked potentials and brainstem auditory evoked potentials were not bilaterally evocable. Sural biopsy proved the loss of myelinated nerve fibers, with axonal degeneration, regenerating clusters and onion bulbs. Enzymatically, PRPS1 activity was close to zero in the proband and mildly reduced in his mother, compared with controls. To our knowledge, this is the first report of CMTX5 in a Chinese population. The genetic finding has expanded the genotypic spectrum of PRPS1 mutations.
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