ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Spectrin is the major protein of the membrane erythrocyte skeleton. More recently, homologous but non-identical spectrins (fodrins) were also found in various non-erythroid tissues. Spectrin mRNA in erythroid and various non-erythroid cells was examined by direct hybridization with human α-spectrin, β-spectrin (erythroid spectrins), and α-fodrin (non-erythroid spectrin) cDNA probes. Northern blot analysis of poly (A)+ RNA revealed a distinct pattern of expression in erythroid vs. non-erythroid cells. Erythroid cells from early erythroblasts to reticulocyte stage expressed two mRNA species of β-spectrin, whereas they expressed only a single speeies of α-spectrin, and no α-fodrin mRNA. In contrast, non-erythroid cells (platelets, myeloid cells, liver, muscle, heart, cerebellum, and eye lens) expressed either no α-spectrin mRNA or a different molecular weight transcript(s) of this gene, and a single species of β-fodrin mRNA. Additionally, they also expressed from none to multiple species of β-spectrin, and these were of different molecular size(s) from that found in erythroid cells (with the exception of platelets). Transcripts of non-erythroid spectrin, α-fodrin, were found as a single copy only in non-erythroid tissues. Human and murine erythroleukemia cells expressed both erythroid spectrin transcripts in addition to α-fodrin and raise the possibility that erythroid progenitors may have the potential to express both erythroid and non-erythroid species. These data indicated that several mRNA species of β-spectrin could be detected in both erythroid and some non-erythroid cells. Whether multiple spectrin peptides could also be found with functional heterogneity is unclear. However, in each case, the pattern combination observed appeared to be tissue-specific.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041440215
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