Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q00604 (X-linked)
 16,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several genes expressed in kidney and other tissues determine phosphate homeostasis in extracellular fluid. The major form of inherited hypophosphatemia in humans involves an X-linked locus (HPDR, Xp22.31-p21.3). It has two murine homologues (Hyp and Gy) which map to closely-linked but separate loci (crossover value 0.4%-0.8%). Both murine mutations impair Na(+)-phosphate cotransport in renal brush border membrane; an associated renal disorder of 1,25-dihydroxyvitamin D3 (1,25(OH)2D) metabolism has been characterized in Hyp mice. Whereas experiments with cultured Hyp renal epithelium indicate that the gene is expressed in kidney, studies showing the development of the mutant renal phenotype in normal mice parabiosed to Hyp mice implicate a circulating factor; these findings can be reconciled if the humoral factor is of renal origin. The gene dose effect of HPDR, Hyp and Gy on serum phosphorus values is consistently deviant and heterozygotes resemble affected hemizygotes. The deviant effect is also seen on renal phosphate transport; all mutant females (Hyp/Hyp and Hyp/+) have similar phenotypes. On the other hand, there is a normal gene dose effect of HPDR in mineralized tissue; tooth PRATIO (pulp area/tooth area) values for heterozygotes are distributed between those for affected males and normals. The tooth data imply that the X chromosome locus is expressed in both renal and non-renal cells. The polypeptide product of the X chromosome gene(s) is still unknown.
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PMID:Conserved loci on the X chromosome confer phosphate homeostasis in mice and humans. 217 24

Several highly homologous glyceraldehyde-3-phosphate dehydrogenase (GAPD)-related sequences have been identified previously in human DNA by Southern blot analysis. Protein studies have identified only a single expressed locus for this major glycolytic enzyme, and this maps to chromosome 12p13. Sequence analysis of a GAPD muscle cDNA clone and a GAPD-related clone retrieved from an X-chromosome recombinant library showed that the latter was a processed pseudogene that maps to Xp11-p21. In this study, we have determined the chromosomal locations of several of the additional GAPD-related human sequences using a short 3' end sequence from the cDNA to probe DNA from a series of human-rodent somatic cell hybrids on Southern blots. Eight HindIII GAPD-related sequences detected at high stringency have been mapped to 6 different chromosomes. Several of the additional sequences detected at more moderate stringency have been localized to a further 10 chromosomal sites. Together, these sites constitute the known expressed locus, the known X-linked pseudogene, and 15 GAPD-like loci.
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PMID:Members of the human glyceraldehyde-3-phosphate dehydrogenase-related gene family map to dispersed chromosomal locations. 279 78

Eleven families with X-linked dominant hypophosphataemic rickets (HPDR) have been typed for a series of X chromosome markers. Linkage with probe 99.6 (DXS41) was demonstrated with a peak lod score of 4.82 at 10% recombination. Multilocus linkage analysis showed that HPDR maps distal to 99.6; this probe has previously been located at Xp22.31-p21.3 by in situ hybridisation. In the mouse hypophosphataemia (Hyp) maps to the distal part of the X chromosome; our location in man is consistent with a scheme which relates the mouse and human X chromosomes by two rearrangements. No marker has yet been found which shows no recombination with HPDR.
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PMID:Mapping of human X-linked hypophosphataemic rickets by multilocus linkage analysis. 301 70

The physiological correlation between nucleoside-diphosphate kinases (NDP-kinases) and the 21-kDa guanine nucleotide-binding proteins (G1 and G2) which are copurified with the enzymes from the cell membrane fractions of Ehrlich ascites tumor cells has been biochemically investigated in vitro. We found that: incubation of the phosphoenzyme (enzyme-bound high-energy phosphate intermediate) of NDP-kinases (F-I and F-II) with one of the nucleoside 5'-diphosphates in the presence of 1 mM Mg2+ or 0.25 mM Ca2+ results in the rapid formation of nucleoside 5'-triphosphates without strict base specificity; GDP on the guanine nucleotide-binding proteins (G1, G2 and recombinant v-rasH p21) acts as a phosphate acceptor for the high-energy phosphates of the phosphoenzyme in the presence of 0.25 mM Ca2+; and [32P]GTP is preferentially formed from the 32P-labelled phosphoenzyme F-I and GDP-bound G1 or GDP-bound recombinant v-rasH p21 protein, even if any other nucleoside 5'-diphosphates are present in the reaction mixture. Although [32P]GTP formed was bound with the guanine nucleotide-binding proteins, it was immediately hydrolyzed by the proteins themselves in the presence of 5 mM Mg2+, but not in the presence of 0.25 mM Ca2+. Available evidence suggests that NDP-kinase may be responsible for the activation of the guanine nucleotide-binding proteins (G1, G2 and p21 proteins) through phosphate transfer by the enzyme.
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PMID:Physiological correlation between nucleoside-diphosphate kinases and the 21-kDa guanine-nucleotide binding proteins copurified with the enzymes from the cell membrane fractions of Ehrlich ascites tumor cells. 303 93

In a patient suffering from X-linked chronic granulomatous disease (X-CGD)--a disorder of phagocytesuperoxide generation--and McLeod syndrome, characterized by the absence of the red cell Kell antigen, we identified a deletion of the entire X-CGD gene by means of DNA hybridization with a cDNA probe. Our findings suggest that the X-CGD and McLeod loci are physically close in the p21 region of the X chromosome proximal to the Duchenne muscular dystrophy locus.
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PMID:Gene deletion in a patient with chronic granulomatous disease and McLeod syndrome: fine mapping of the Xk gene locus. 333 97

Phosphorus nuclear magnetic resonance spectra of the Ha-ras oncogene product p21 and its nucleotide complexes have been obtained. It is shown that the 31P nuclear magnetic resonance spectra of a number of nucleotide-enzyme complexes show some common features. In particular, the chemical shift values of the beta-phosphorus resonance of enzyme-bound NTP and NDP (N = A, G) of hydrolases exhibit a downfield shift virtually identical for myosin, elongation factor Tu, and the Ha-ras oncogene product p21. This suggests that the stereochemistry around the beta-phosphorus might be similar in these compounds.
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PMID:31P-NMR spectra of the Ha-ras p21.nucleotide complexes. 348 74

We have examined the relationship between chromosomal location and regulation of the two human genes encoding the sarcomeric muscle actins. The human genes encoding skeletal alpha-actin and cardiac alpha-actin are co-expressed in both human skeletal muscle and heart. We have subcloned a single-copy DNA fragment from an intervening sequence in the human cardiac alpha-actin gene and a single-copy DNA sequence from the 3' untranslated region of a human skeletal alpha-actin cDNA. Using these two gene-specific probes, we examined DNA isolated from human-mouse somatic cell hybrid lines segregating human chromosomes. We observed the segregation of restriction endonuclease-generated DNA cleavage fragments that hybridize to the two probes. The two striated muscle genes do not co-segregate and are on different autosomes. The human cardiac alpha-actin gene (ACTC) is on chromosome 15 in the q11----qter region whereas the skeletal alpha-actin gene (ACTSK) is on chromosome 1 in the p21----qter region. The co-expression of these two genes is not a function of chromosomal linkage. Neither of these muscle genes can be the primary target resulting in X-linked muscular dystrophies.
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PMID:Chromosomal location of the co-expressed human skeletal and cardiac actin genes. 658 14

We describe an infant with adrenal insufficiency who was subsequently diagnosed with Duchenne muscular dystrophy (DMD) and hyperglycerolemia due to glycerol kinase deficiency. Karyotyping showed a deletion on the short arm of the X chromosome (p21.1 to p22.1). Molecular mapping revealed that the deletion extended from the 3' end of the DMD gene to a site telomeric to the loci for X-linked congenital adrenal hypoplasia and glycerol kinase deficiency. These results are diagnostic for an Xp21 contiguous gene deletion syndrome--so named because the deletion manifests as a distinctive cluster of otherwise unrelated single-gene disorders in the same individual. The Xp21 syndrome should be considered in any infant with adrenal insufficiency. Measurement of serum triglycerides (without glycerol blanking) and creatine kinase activity are simple screening tests that may facilitate early diagnosis and appropriate genetic counseling about risks of recurrence in subsequent offspring.
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PMID:Congenital adrenal hypoplasia, Duchenne muscular dystrophy, and glycerol kinase deficiency: importance of laboratory investigations in delineating a contiguous gene deletion syndrome. 795 86

In view of recent advancement in the field of medical genetics, one approach to work-up a dysmorphic patient is to focus on how to study the patient clinically, cytogenetically, and molecularly. A clear understanding about major and minor anomalies, classification and terminologies of errors of morphogenesis, history taking, physical examination, laboratory studies including molecular cytogenetic techniques, genomic imprinting, uniparental disomy, and mosaicism is essential. Several clinical cases from my own experience are provided to illustrate my approach to work-up of dysmorphic patients. Case 1 was a newborn with multiple congenital anomalies (MCA) and a de novo dup (1) (pter-->q25::q12-->qter). Fluorescent in situ hybridization (FISH) unequivocally identified the duplicated region. Case 2 was a stillborn who had frontonasal dysplasia, arrhinencephaly, and other MCA with 46,XX,-7,+der(7), t(2;7) (q31;q36)mat. Her MCA were due to combined effect of trisomy 2q and monosomy 7q. This case helped to define the physical mapping of the critical region for a mild form of holoprosencephaly to 7q36. Case 3 had a classic de Lange phenotype with genital abnormality and sex reversal (46,XX male). Presence of SRY suggests X-Y interchange during paternal meiosis I. Case 4 was a female with primary amenorrhea, short stature, and 45,X/46,X,idic(Y)/47,X,idic(Y),idic(Y). This case demonstrates the need for molecular analyses to confirm the cytogenetic interpretations and allowed the refinement of the breakpoint in the isodicentric Y and karyotype/phenotype correlations. Case 5 & 6 were half sibs with ambiguous genitalia, minor somatic abnormalities, and dup (X) (p21.2-->p22.11)mat. Limited extent of the Xp duplication in these cases allows assignment of the X-linked sex-reversal (SRVX) locus to Xp21.2-->p22.11.
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PMID:An approach to work-up of dysmorphic patients: clinical, cytogenetic, and molecular aspects. 808 61

Subchromosomal localizations for 19 X-linked expressed sequence tags (ESTs) have been determined. Two ESTs are located in Xq28, adding two novel genes to this disease-rich region. The remaining ESTs are located primarily in the pericentromeric region, with most mapping to Xp11.1-p21.1. YAC and cosmid genomic clones have been isolated for several of these loci. Available cDNAs have been used to characterize the corresponding transcripts by Northern analysis in multiple human tissues.
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PMID:Regional assignment of 19 X-linked ESTs. 828 Nov 54


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