First Author | McMahon AP | Year | 1987 |
Journal | Differentiation | Volume | 34 |
Issue | 1 | Pages | 68-78 |
PubMed ID | 3038643 | Mgi Jnum | J:8797 |
Mgi Id | MGI:57262 | Doi | 10.1111/j.1432-0436.1987.tb00052.x |
Citation | McMahon AP, et al. (1987) cDNA cloning, sequencing and chromosome mapping of a non-erythroid spectrin, human alpha-fodrin [published erratum appears in Differentiation 1987;34(3):241]. Differentiation 34(1):68-78 |
abstractText | Several overlapping cDNA clones encompassing 2760 nucleotides of the alpha-subunit of a human non-erythroid spectrin (termed fodrin) were isolated from a human lung fibroblast cDNA library. DNA and RNA blot analyses indicated that a single copy alpha-fodrin gene encodes a 9-kb transcript. The cDNA clones were sequenced, and all were found to contain long open reading frames. The overlapping regions were identical except for a 60-nucleotide inframe insertion at position 1133 in the composite sequence. This result suggests that at least two distinct transcripts exist in fibroblast cells. The chromosomal location of human alpha-fodrin was assigned to 1p34-1p36.1 by hybridization to somatic cell hybrids, and it is thus distinct from that of human alpha-spectrin which has been mapped to 1q22-1q25. Alignment of the composite 919 amino acids of the predicted protein sequence of human alpha-fodrin with that of human alpha-spectrin indicated that alpha-fodrin has a similar 106-amino-acid repeating structure, which is homologous with alpha-spectrin repeats 7-15. Repeats 10 and 11 are anomalous in sequence and structure from other repeats. A comparison of nucleic acid and amino acid homologies between alpha-spectrin and the alpha-fodrin of several vertebrates indicated that human non-erythroid alpha-fodrin and the common alpha-subunit of erythroid and non-erythroid cells of non-mammalian vertebrates are closely related (90%-96% amino acid homology), whereas alpha-fodrin is only distantly related to the erythroid-specific alpha-spectrin subunit of mammals (55%-59% amino acid homology). These data suggest that mammalian erythroid alpha-spectrin evolved by duplication and rapid divergence from an ancestral alpha-fodrin-like gene. |