Back to Search
Start Over
An Erythroid-Specific Transcript Generates the Soluble Form of NADH-Cytochrome b5 Reductase in Humans
- Source :
- Europe PubMed Central
- Publication Year :
- 1998
- Publisher :
- American Society of Hematology, 1998.
-
Abstract
- Two forms of NADH-cytochrome b5 reductase (b5R), an erythrocyte-restricted soluble form, active in methemoglobin reduction, and a ubiquitous membrane-associated form involved in lipid metabolism, are produced from one gene. In the rat, the two forms are generated from alternative transcripts differing in the first exon, however, biogenesis of human b5R was less understood. Recently, two different transcripts (M and S), differing in the first exon were also described in humans. Here, we have investigated the tissue-specificity and the role of the S-transcript in the generation of soluble b5R. By RNase protection assays designed to simultaneously detect alternative b5R transcripts in the same sample, the S transcript was undetectable in nonerythroid and in erythroleukemic K562 cells induced to differentiate, but was present in terminal erythroblast cultures, and represented a major b5R transcript in reticulocytes. Analysis of the translation products of the M- and S-transcripts in HeLa cells transfected with the corresponding cDNAs demonstrated that the S-transcript generates soluble b5R, presumably from an internal initiation codon. Our results indicate that the S-transcript is expressed at late stages of erythroid maturation to generate soluble b5R.
- Subjects :
- Cytochrome-B(5) Reductase
DNA, Complementary
Erythrocytes
Transcription, Genetic
Molecular Sequence Data
Immunology
Biology
Reductase
HeLa Cell
Transfection
Biochemistry
Exon
Start codon
Erythroblast
Animals
Humans
Amino Acid Sequence
Cytochrome Reductase
Gene
Cytochrome Reductases
Cytochrome b5 reductase
Animal
Cell Differentiation
Cell Biology
Hematology
Rats
Erythrocyte
Rat
Biogenesis
Human
HeLa Cells
Subjects
Details
- ISSN :
- 15280020 and 00064971
- Volume :
- 92
- Database :
- OpenAIRE
- Journal :
- Blood
- Accession number :
- edsair.doi.dedup.....8c1acf0b5eab676391958170818c7d89