Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Charcot-Marie-Tooth (CMT) disease type 1A is an autosomal dominant peripheral neuropathy characterized by slow progressive distal muscle wasting and weakness, and decreased nerve conduction velocities. Most CMT1A cases (>98%) are caused by a duplication of a 1.5 Mb region on the short arm of chromosome 17 containing the PMP22 gene. A couple with a previous history of CMT followed by termination of pregnancy was referred to our centre for preimplantation genetic diagnosis (PGD). The husband carries the CMT1A duplication which can be detected by polymerase chain reaction (PCR) analysis using polymorphic (CA)n markers localized within the duplication. PCR amplification of genomic DNA of the parents-to-be with one of the two primers labelled with fluorescein, followed by automated laser fluorescence (ALF) gel electrophoresis of the amplified fragments allows the distinction between both genotypes. Embryos obtained after intracytoplasmic sperm injection (ICSI) were evaluated for the presence of the normal allele of the father. PCR with single Epstein-Barr virus-transformed lymphoblasts and blastomeres resulted in 91.4 and 93.5% amplification efficiency respectively, whereas none of the blank controls gave a positive signal. Allele drop-out (ADO) was observed in eight out of 32 lymphoblasts (25%) or in five out of 21 blastomeres (23.8%). However, within this set-up ADO will never lead to transfer of an affected embryo. A first ICSI-PGD cycle did not result in embryo transfer for the patient. A second cycle involved 10 mature oocytes of which eight were fertilized, resulting in five embryos for biopsy. Two unaffected embryos were available for transfer and resulted in a singleton pregnancy. The genotype of the fetus has been confirmed healthy by chorionic villus sampling.
Mol Hum Reprod 1998 Oct
PMID:Pregnancy after preimplantation genetic diagnosis for Charcot-Marie-Tooth disease type 1A. 980 80

Spinal muscular atrophy (SMA) is a common autosomal recessive neuromuscular disorder characterized by degeneration of motor neurons of the spinal cord and muscular atrophy. SMA is caused by alterations to the survival of motor neuron (SMN) gene, the function of which has hitherto been unclear. Here, we present immunoblot analyses showing that normal SMN protein expression undergoes a marked decay in the postnatal period compared with fetal development. Morphological and immunohistochemical analyses of the SMN protein in human fetal tissues showed a general distribution in the cytoplasm, except in muscle cells, where SMN protein was immunolocalized to large cytoplasmic dot-like structures and was tightly associated with membrane-free heavy sedimenting complexes. These cytoplasmic structures were similar in size to gem. The SMN protein was markedly deficient in tissues derived from type I SMA fetuses, including skeletal muscles and, as previously shown, spinal cord. While our data do not help decide whether SMA results from impaired SMN expression in spinal cord, skeletal muscle or both, they suggest a requirement for SMN protein during embryo-fetal development.
Hum Mol Genet 1998 Nov
PMID:The distribution of SMN protein complex in human fetal tissues and its alteration in spinal muscular atrophy. 981 37

Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are responsible for autosomal recessive proximal spinal muscular atrophy (SMA). SMN orthologues have been identified in the nematode worm Caenorhabditis elegans and the yeast Schizosaccharomyces pombe but, to date, no human paralogues have been described. Here we describe identification and characterization of an SMN-related protein (SMNrp) gene that encodes a novel protein of 239 amino acids, which has recently been identified as a constituent of the spliceosome complex and designated SPF30. Significant similarity to the SMN protein is apparent only within a central region of SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped to chromosome 10q23. It is differentially expressed, with abundant levels in skeletal muscle. An exclusively nuclear localization for SMNrp in cultured cells and muscle sections was revealed using GFP fusion constructs and thereafter confirmed with a polyclonal antibody raised against SMNrp. Overexpression of SMNrp as a fusion protein in HeLa cells in culture induced dose-dependent apoptosis with positive TUNEL staining. In addition to a possible role for this protein as a pro-apoptotic factor, SMN and its related protein share significant similarities in sequence and cellular function.
Hum Mol Genet 1998 Dec
PMID:Characterization of a gene encoding survival motor neuron (SMN)-related protein, a constituent of the spliceosome complex. 981 34

Spinal bulbar muscular atrophy is a neurodegenerative disorder caused by a polyglutamine expansion in the androgen receptor (AR). We show in transiently transfected HeLa cells that an AR containing 48 glutamines (ARQ48) accumulates in a hormone-dependent manner in both cytoplasmic and nuclear aggregates. Electron microscopy reveals both types of aggregates to have a similar ultrastructure. ARQ48 aggregates sequester mitochondria and steroid receptor coactivator 1 and stain positively for NEDD8, Hsp70, Hsp90 and HDJ-2/HSDJ. Co-expression of HDJ-2/HSDJ significantly represses aggregate formation. ARQ48 aggregates also label with antibodies recognizing the PA700 proteasome caps but not 20S core particles. These results suggest that ARQ48 accumulates due to protein misfolding and a breakdown in proteolytic processing. Furthermore, the homeostatic disturbances associated with aggregate formation may affect normal cell function.
Hum Mol Genet 1999 May
PMID:Polyglutamine-expanded androgen receptors form aggregates that sequester heat shock proteins, proteasome components and SRC-1, and are suppressed by the HDJ-2 chaperone. 1019 62

During the last years many investigations have shown that a major catalyst within the mechanism of skeletal muscle wasting occurring under conditions like sepsis, injuries, trauma, cancer cachexia, chronic acidosis, fasting, glucocorticoid treatment, and insulinopenia is the ubiquitin-proteasome system. Evidence for this was obtained by findings that the rate of ATP-dependent protein degradation is increased, that m-RNA concentrations of several proteasome subunits and ubiquitin are increased and the amount of ubiquitin-protein conjugates is elevated under these conditions. Additionally, the enhanced protein breakdown was shown to be suppressed by proteasome inhibitors. In the present report we show that most but not all of the proteolytic activities of partially purified 20S/26S proteasomes from skeletal muscle of rats increase after induction of Diabetes mellitus. This finding suggests that part of the mechanism of acceleration of muscle protein breakdown is due to changes in proteasome activities.
Mol Biol Rep 1999 Apr
PMID:Alterations of proteasome activities in skeletal muscle tissue of diabetic rats. 1036 52

Muscular functions decline and muscle mass decreases during ageing. In the rat, there is a 27% decrease in muscle protein between 18 and 34 months of age. We examined age-related changes in the proteasome-dependent proteolytic pathway in rats at 4, 18, 24, 29 and 34 months of age. The three best characterised activities of the proteasome (chymotrypsin-like, trypsin-like and peptidylglutamyl peptide hydrolase) increased to 29 months and then decreased in the senescent animal. These variations in activity were accompanied by an identical change in the quantity of 20S proteasome measured by Western blot, whereas the S4 subunit of the 19S regulator and the quantity of ubiquitin-linked proteins remained constant. mRNA of subunits C3, C5, C9, and S4 increased in the senescent animal, but ubiquitin mRNA levels were unchanged. These findings suggest that the 20S proteasome may be partly responsible for the muscular atrophy observed during ageing in the rat.
Mol Biol Rep 1999 Apr
PMID:Changes in 20S proteasome activity during ageing of the LOU rat. 1036 53

The development of pharmacological approaches for preventing the loss of muscle proteins would be extremely valuable for cachectic patients. For example, severe wasting in cancer patients correlates with a reduced efficacy of chemotherapy and radiotherapy. Pentoxifylline (PTX) is a very inexpensive xanthine derivative, which is widely used in humans as a haemorheological agent, and inhibits tumor necrosis factor transcription. We have shown here that a daily administration of PTX prevents muscle atrophy and suppresses increased protein breakdown in Yoshida sarcoma-bearing rats by inhibiting the activation of a nonlysosomal, Ca(2+)-independent proteolytic pathway. PTX blocked the ubiquitin pathway, apparently by suppressing the enhanced expression of ubiquitin, the 14-kDa ubiquitin conjugating enzyme E2, and the C2 20S proteasome subunit in muscle from cancer rats. The 19S complex and 11S regulator associate with the 20S proteasome and regulate its peptidase activities. The mRNA levels for the ATPase subunit MSS1 of the 19S complex increased in cancer cachexia, in contrast with mRNAs of other regulatory subunits. This adaptation was suppressed by PTX, suggesting that the drug inhibited the activation of the 26S proteasome. This is the first demonstration of a pharmacological manipulation of the ubiquitin-proteasome pathway in cachexia with a drug which is well tolerated in humans. Overall, the data suggest that PTX can prevent muscle wasting in situations where tumor necrosis factor production rises, including cancer, sepsis, AIDS and trauma.
Mol Biol Rep 1999 Apr
PMID:Manipulation of the ubiquitin-proteasome pathway in cachexia: pentoxifylline suppresses the activation of 20S and 26S proteasomes in muscles from tumor-bearing rats. 1036 54

In mammals, the postnatal loss of more than 99% of female germ cells is due mainly to the process of ovarian follicular atresia. Atresia is known to be mediated by apoptotic granulosa cell-death. Here we show the involvement of neuronal apoptosis inhibitory protein (NAIP) in ovarian folliculogenesis in which it prevents granulosa cell-death. NAIP has been isolated in association with a neurodegenerative disorder, spinal muscular atrophy (SMA), in which it has been shown to suppress mammalian cell-death induced by a variety of stimuli (Liston et al., 1996, Nature 379:349-353). In an in situ hybridization analysis with mouse ovaries, active expression of NAIP mRNA was localized in the granulosa cells of developing follicles from the primary stage to the Graafian stages, whereas the NAIP gene was not expressed or was weakly expressed in follicles that might be undergoing atresia. Gonadotropin, which is known to inhibit apoptosis in ovarian follicles, caused a 2.4-fold increase in NAIP gene expression in the ovary. To study the role of ovarian NAIP, antisense NAIP oligonucleotides were locally delivered into the ovarian bursa. Suppression of ovarian NAIP expression with antisense oligonucleotides evoked a decrease in the number of morphologically normal ovulated oocytes, implying an indirect involvement of NAIP in germ cell development by enhancing the survival of granulosa cells. These findings suggest that gonadotropin-inducible NAIP may indirectly affect oocyte survival as a result of the inhibition of apoptotic granulosa cell-death during folliculogenesis.
Mol Reprod Dev 1999 Oct
PMID:Neuronal apoptosis inhibitory protein (NAIP) may enhance the survival of granulosa cells thus indirectly affecting oocyte survival. 1047 69

A great majority of patients seeking preimplantation genetic diagnosis (PGD) are women >35 years of age. In addition to being carriers for single gene defects, these women also have a higher risk of having children with Down's syndrome (trisomy 21). For these patients, it would be advantageous if a diagnostic test for trisomy 21 was developed, which could be used in conjunction with tests for single gene defects. Here, we assessed the feasibility of developing an accurate genetic test for diagnosing trisomy 21 and the mutation causing spinal muscular atrophy (SMA) in single cells using multiplex fluorescence polymerase chain reaction (PCR). Single- and two-round PCR were developed using a combination of primers for the survival motor neuron (SMN) gene exons 7 and 8 and two chromosome 21 short tandem repeats (STRs), D21S226 and D21S11. After only 36 cycles, 88 and 68% of normal single cells were screened for SMA mutations and trisomy 21 respectively. In multiplex PCR using only two primers (SMN exon 7 and D21S11) instead of four, the efficiency of SMA diagnosis was increased to 93%. In the same reactions, the D21S11 alleles were detected in 83% of the normal single cells. Clinical applications of this assay should enable detection of those embryos that have inherited three heterozygous alleles and, therefore, benefit many PGD patients who are at an increased risk of Down's syndrome.
Mol Hum Reprod 1999 Dec
PMID:Assessment of multiplex fluorescent PCR for screening single cells for trisomy 21 and single gene defects. 1058 73

The subcellular localization of the survival motor neuron (SMN) protein, encoded by the spinal muscular atrophy determining gene, was investigated in motor neurons of the developing and adult rat spinal cord by light and electron microscopy immunocytochemistry. The experiments were carried out with a panel of anti-SMN antibodies, all recognizing an SMN-specific protein band at 39 kDa in HeLa cells and rat spinal cord protein extracts. SMN protein expression decreased during postnatal spinal cord development, but it remained unchanged in distribution and intensity in motor neurons at all ages examined. SMN protein was mainly organized in immunoreactive aggregates sparse in the nucleoplasm and cytoplasm of both mature and developing motor neurons, and it was more rarely localized within the endoplasmic reticulum and in apposition to the external mitochondrial membrane. Most strikingly, the SMN protein was found in association with cytoskeletal elements in spinal dendrites and axons, where it was particularly evident during postnatal development. The present findings suggest that SMN protein may be transported via axoplasmic flow in maturing neurons. Given the RNA-binding activity of SMN, the SMN protein could be involved in the transport of specific mRNAs in axons and dendrites of motor neurons. The reduced transport of specific mRNAs within motor neurons during development could play a role in the motoneuronal degeneration and impaired axonal sprouting observed in spinal muscular atrophy.
Hum Mol Genet 2000 Jan 01
PMID:Subcellular localization and axonal transport of the survival motor neuron (SMN) protein in the developing rat spinal cord. 1058 77


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