Normal V(D)J coding junction formation in DNA ligase I deficiency syndromes.
Bloom syndrome and a clinically related syndrome represented by the cell line 46BR have been associated with reduction in DNA ligase I activity. In these syndromes, DNA ligase I deficiency severely impairs the development and function of the immune system. We undertook analysis of DNA ligase I-deficient cells to determine whether the observed immune deficiency is attributable to a perturbation in the process of V(D)J recombination. V(D)J recombination in Bloom syndrome cell lines and 46BR was examined by a transient transfection assay. No effect on the fidelity of coding and signal junction formation in DNA ligase I-deficient cells was observed. The frequency of V(D)J recombination in DNA ligase I-deficient cells was also examined using recombination substrates modified to function in human cells. Similar recombination frequencies were observed in normal and DNA ligase I-deficient cells, demonstrating that the efficiency of the V(D)J recombination process is unaffected by alterations in DNA ligase I activity. Rearranged immunoglobulin loci from Bloom syndrome cell lines and patient material were molecularly cloned by an inverse polymerase chain reaction strategy which should be applicable to a variety of human immunodeficiency syndromes and were indistinguishable from those found in normal bone marrow samples. Our data argue that the immune system defects associated with DNA ligase I deficiency do not result from perturbation of the V(D)J recombination pathway.
Petrini
J H
JH
Division of Tumor Immunology, Dana Farber Cancer Institute, Boston, MA 02115.
Donovan
J W
JW
Dimare
C
C
Weaver
D T
DT
D001483:Base Sequence; D001816:Bloom Syndrome / Q000201:enzymology / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000172:deficiency*; D004260:DNA Repair / Q000235:genetics; D015321:Gene Rearrangement; D005803:Genes, Immunoglobulin; D006801:Humans; D007128:Immunoglobulin Fragments / Q000235:genetics; D007153:Immunologic Deficiency Syndromes / Q000201:enzymology / Q000235:genetics* / Q000276:immunology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic
D007128:Immunoglobulin Fragments; C000607892:LIG1 protein, human; D011088:DNA Ligases; D000072481:DNA Ligase ATP