Genetic control of neutrophil superoxide production in diabetes-resistant ALR/Lt mice.
The neutrophil oxidative burst reaction differentiates ALR/Lt mice, known for an unusual systemic elevation of antioxidant defenses, from ALS/Lt mice, a related strain known for reduced ability to withstand oxidative stress. Neutrophils from marrow of ALS mice produced a normal neutrophil oxidative burst following phorbol ester stimulation. In contrast, ALR mice exhibited a markedly suppressed superoxide burst. F1 progeny from reciprocal outcrosses between ALR and ALS mice exhibited an intermediate burst level, higher than ALR but significantly lower than ALS. To elucidate the genetic basis for this strain difference, F1 mice were backcrossed to ALS mice, and marrow neutrophils isolated from the progeny were phenotyped for oxidative burst capacity. A genome-wide sweep using polymorphic markers distinguishing the two parental strains was performed to map the trait. A 1:1 phenotypic distribution was observed, and a locus (Suppressor of superoxide production, Susp) controlling this phenotype was mapped to Chromosome 3 near D3Mit241 at 33.1 cM. This locus probably represents an important regulatory element in the overall ALR strain resistance to oxidative stress, since diminished ability to mount a neutrophil burst in backcross segregants correlated with elevated hepatic superoxide dismutase 1 (SOD1) activity, an ALR strain characteristic.
Mathews
Clayton E
CE
The Jackson Laboratory, Bar Harbor, ME, USA. cem65@pitt.edu
Dunn
Brian D
BD
Hannigan
Michael O
MO
Huang
Chi-Kuang
CK
Leiter
Edward H
EH
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D003921:Diabetes Mellitus, Experimental / Q000235:genetics*; D005260:Female; D005799:Genes, Dominant; D005819:Genetic Markers / Q000502:physiology; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005947:Glucose / Q000494:pharmacology; D007113:Immunity, Innate / Q000502:physiology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009504:Neutrophils / Q000201:enzymology* / Q000378:metabolism; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism*
D001786:Blood Glucose; D005819:Genetic Markers; D013481:Superoxides; D013482:Superoxide Dismutase; D005947:Glucose