Duplication of an amphioxus myogenic bHLH gene is independent of vertebrate myogenic bHLH gene duplication
Gene duplication is thought to be a major genetic change that may have permitted the evolution of vertebrates from invertebrates. The myogenic genes encode basic helix-loop-helix (bHLH) transcriptional factors essential for the formation of skeletal muscle. The invertebrate genome contains only a si...
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Published in | Gene Vol. 171; no. 2; pp. 231 - 236 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Netherlands
Elsevier B.V
01.06.1996
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Subjects | |
Online Access | Get full text |
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Summary: | Gene duplication is thought to be a major genetic change that may have permitted the evolution of vertebrates from invertebrates. The myogenic genes encode basic helix-loop-helix (bHLH) transcriptional factors essential for the formation of skeletal muscle. The invertebrate genome contains only a single myogenic
bHLH gene, whereas the vertebrate genome contains four (
MyoD, Myf-5, myogenin and
MRF4). Since the tunicate genome contains a single myogenic
bHLH gene, its duplication might have occurred some time during chordate evolution. To determine whether the duplication of the myogenic
bHLH gene occurred prior to, or after the divergence of vertebrates from the cephalochordate lineage, we amplified target fragments from the amphioxus,
Branchiostoma floridae, by means of PCR. Sequence analysis and genomic Southern analysis revealed that the amphioxus genome contains two myogenic
bHLH genes (
BMD1 and
BMD2). A comparison of the amino acid sequences in the bHLH domain between BMD1, BMD2 and four vertebrate myogenic
bHLH gene products, however, showed that neither
BMD1 nor
BMD2 resembled any of the four genes. These results suggested that the duplication of amphioxus myogenic
bHLH gene occurred independently of that leading to the four myogenic
bHLH genes in vertebrates. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0378-1119 1879-0038 |
DOI: | 10.1016/0378-1119(96)00174-6 |