TY  - JOUR
A1  - Raulf, F.
A1  - Robertson, S. M.
A1  - Schartl, Manfred
T1  - Evolution of the neuron-specific alternative splicing product of the c-src proto-oncogene
N2  - The observation of a slower migrating form of pp6oc-src in neural tissue of chicken and mouse has recently been shown to be due to an alternative transcript form of tbe c-src gene (Martinez et al.: Science 237:411-415, 1987; Levy et al.: Mol Cell Bio17:4142- 4145, 1987). An insertion of 18 basepairs between exons 3 and 4, presumed to be due to alternative splicing of a mini-exon, gives rise to six amino acid residues not found in the non-neuronal (termed flbroblastic) form of pp60\(^{c-src}\). Wehave addressed the question of the evolutionary origin of the c-src neuronal insert · and its functional signiflcance regarding neural-speciflc expression of the c-src gene. To this end we have investigated whether the c-src gene of a lower verlebrate (the teleost fish Xiphophorus) gives rise to a neural-specific transcript in an analogous manner. We could show that the fish c-src gene does encode for a "fibroblastic" and a "neuronal" form of transcript and that the neuronal transcript does indeed arise by way of alternative splicing of a mini-exon. The miniexon is also 18 basepairs long and we could demoostrate directly that this exon lies within the intron separating exons 3 and 4. For comparative purposes we have examined whether the fish c-yes gene, the member of the src gene family most closely related to c-src, also encodes a neural tissue-specific transcript. No evidence for a second transcript form in brain was obtained. This result suggests that the mini-exon arose within the c-src gene lineage sometime between the srclyes gene duplication event and the divergence of the evolutionary lineage giving rise to the teleost fish. Published genomic sequence of src-related genes in Drosophila and our own results with Hydra demoostrate no intron in these species at the analogous location, consistent with first appearance of this mini-exon sometime between 550 and 400 million years ago.
KW  - Physiologische Chemie
KW  - Xiphophorus
KW  - teleost flsh
KW  - polymerase
KW  - chain reaction
KW  - RT -PCR
KW  - mini-exon
KW  - pp6oc-src
Y1  - 1989
UR  - https://opus.bibliothek.uni-wuerzburg.de/frontdoor/index/index/docId/5928
UR  - https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-61796
ER  -