High-throughput screening of mouse knockout lines identifies true lean and obese phenotypes.
We developed a high-throughput approach to knockout (KO) and phenotype mouse orthologs of the 5,000 potential drug targets in the human genome. As part of the phenotypic screen, dual-energy X-ray absorptiometry (DXA) technology estimates body-fat stores in eight KO and four wild-type (WT) littermate chow-fed mice from each line. Normalized % body fat (nBF) (mean KO % body fat/mean WT littermate % body fat) values from the first 2322 lines with viable KO mice at 14 weeks of age showed a normal distribution. We chose to determine how well this screen identifies body-fat phenotypes by selecting 13 of these 2322 KO lines to serve as benchmarks based on their published lean or obese phenotype on a chow diet. The nBF values for the eight benchmark KO lines with a lean phenotype were > or =1 s.d. below the mean for seven (perilipin, SCD1, CB1, MCH1R, PTP1B, GPAT1, PIP5K2B) but close to the mean for NPY Y4R. The nBF values for the five benchmark KO lines with an obese phenotype were >2 s.d. above the mean for four (MC4R, MC3R, BRS3, translin) but close to the mean for 5HT2cR. This screen also identifies novel body-fat phenotypes as exemplified by the obese kinase suppressor of ras 2 (KSR2) KO mice. These body-fat phenotypes were confirmed upon studying additional cohorts of mice for KSR2 and all 13 benchmark KO lines. This simple and cost-effective screen appears capable of identifying genes with a role in regulating mammalian body fat.
Brommage
Robert
R
Lexicon Pharmaceuticals, Inc., The Woodlands, Texas, USA.
Desai
Urvi
U
Revelli
Jean-Pierre
JP
Donoviel
Dorit B
DB
Fontenot
Gregory K
GK
Dacosta
Christopher M
CM
Smith
Deon D
DD
Kirkpatrick
Laura L
LL
Coker
Kenneth J
KJ
Donoviel
Michael S
MS
Eberhart
Derek E
DE
Holt
Kathleen H
KH
Kelly
Michael R
MR
Paradee
William J
WJ
Philips
Anne V
AV
Platt
Kenneth A
KA
Suwanichkul
Adisak
A
Hansen
Gwenn M
GM
Sands
Arthur T
AT
Zambrowicz
Brian P
BP
Powell
David R
DR
D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000000981:diagnostic imaging / Q000503:physiopathology*; D050154:Adiposity / Q000235:genetics*; D000818:Animals; D004041:Dietary Fats / Q000008:administration & dosage; D004195:Disease Models, Animal; D005260:Female; D005838:Genotype; D008279:Magnetic Resonance Imaging; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009765:Obesity / Q000000981:diagnostic imaging / Q000235:genetics / Q000503:physiopathology*; D010641:Phenotype; D015203:Reproducibility of Results; D013851:Thinness / Q000000981:diagnostic imaging / Q000235:genetics / Q000503:physiopathology*
D004041:Dietary Fats