Cloning and gene map assignment of the Xiphophorus DNA ligase 1 gene |
| |
Authors: | Walter RB; Rolig RL; Kozak KA; McEntire B; Morizot DC; Nairn RS |
| |
Institution: | Department of Biology, Southwest Texas State University, San Marcos 78666. |
| |
Abstract: | Fishes represent the stem vertebrate condition and have maintained several
gene arrangements common to mammalian genomes throughout the 450 Myr of
divergence from a common ancestor. One such syntenic arrangement includes
the GPI-PEPD enzyme association on Xiphophorus linkage group IV and human
chromosome 19. Previously we assigned the Xiphophorus homologue of the
human ERCC2 gene to linkage group U5 in tight association with the CKM
locus. CKM is also tightly linked to the ERCC2 locus on human chromosome
19, leading to speculation that human chromosome 19 may have arisen by
fusion of two ancestral linkage groups which have been maintained in
fishes. To investigate this hypothesis further, we isolated and sequenced
Xiphophorus fish genomic regions exhibiting considerable sequence
similarity to the human DNA ligase 1 amino acid sequence. Comparison of the
fish DNA ligase sequence with those of other species suggests several modes
of amino acid conservation in this gene. A 2.2-kb restriction fragment
containing part of an X. maculatus DNA ligase 1 exon was used in backcross
hybrid mapping with 12 enzyme or RFLP loci. Significant linkage was
observed between the nucleoside phosphorylase (NP2) and the DNA ligase
(LIG1) loci on Xiphophorus linkage group VI. This assignment suggests that
the association of four DNA repair-related genes on human chromosome 19 may
be the result of chance chromosomal rearrangements.
|
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|