Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Drug
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Target Concepts:
Gene/Protein
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Query: UMLS:C0002736 (
amyotrophic lateral sclerosis
)
19,048
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In earlier studies of sporadic
amyotrophic lateral sclerosis
(
ALS
), a disease of unknown etiology, the amount of metallothioneins (MTs), a group of small (6-7 kDa) metal-binding proteins, appeared higher in liver, kidney and spinal cord from patients than from non-neurologic controls. Immunohistochemically, the expression of MT in the central nervous system appeared limited to glia. Since the highly conserved MTs isotypes share antigenic epitopes, they could not be distinguished by immunological methods. It thus proved necessary to estimate the expression of each individual MT messenger ribonucleic acid (mRNA) by performing reverse transcriptase polymerase chain reaction (RT-PCR)-mediated analysis of tissue samples. Tissues selected included liver, motor cortex and cervical cord at C6; MT mRNAs analyzed included MT1A, 1B, 1E, 1F, 1G, 2A, and 3. Also, special care was taken to avoid interference by amplification of the 6 MT pseudogenes. Except of MT3, already known as brain-specific, and
MT1B
which was not expressed in any tissue, mRNA levels of the other MT genes tended to be higher in
ALS
than in control liver samples, but the differences did not attain statistical significance. In the nervous system, the diverse MT genes were expressed over a greater range in
ALS
than in controls, but exhibited no change in a consistent direction. At the motor cortex, changes seemed to be less pronounced than at C6. MT3 was expressed in the motor cortex and the cord. The results provide no evidence for either the induction of a specific MT repertoire, or for the inability of glia to express any MT gene in
ALS
. Because the semi-quantitative RT-PCR technique does not permit detailed comparisons between the subtypes of MT expressed in the various tissues, the question whether a single inductor may be held responsible for the elevation of MT in the
ALS
liver and nervous system remains open. In conclusion,
ALS
tissue remains capable of expressing all the major MT genes. MT, present in protoplasmic glia, arises locally and is not secondary to increases of hepatic or renal MT. Because MT3 is also expressed by the normal and
ALS
spinal cord, it is a central nervous system-specific and not only a brain-specific protein. Thus, the excess of MT in
ALS
liver seems to be an effect of slower catabolism rather than faster synthesis of protein.
...
PMID:Expression of different metallothionein messenger ribonucleic acids in motor cortex, spinal cord and liver from patients with amyotrophic lateral sclerosis. 890 18