Differenetial Gene Expression in Limbs of Wild Type and Lmx1b KO mice during limb dorsalization (e11.5, e12.5 & e13.5)

Lmx1b regulates dorsalization of limb fates, but the mechanism of this regulation has not been characterized. To identify candidate genes regulated by Lmx1b we compared the limbs from Lmx1b KO mice to wild type mice during limb dorsalization (e11.5-13.5). Differentially expressed genes that we common to all three stages examined were considered to be likely candidates for Lmx1b regulation and further evaluated. At 11.5 and 12.5 dpc, embryos were harvested and the limb buds with the limb girdles were isolated. Embryos at 13.5dpc were also harvested and their distal limb buds (zeugopods and autopods) were isolated. Embryos were genotyped to confirm Lmx1b homozygosity (-/- or +/+). RNA from embryonic forelimbs and hindlimbs of wild type (WT) and Lmx1b KO mice was harvested using the Rneasy Kit (Qiagen). RNA was pooled to decrease genetic variability, i.e., six limbs at 11.5 dpc, three limbs at 12.5 dpc and six limbs at 13.5 dpc. Duplicate samples were generated using different embryos for each stage and then hybridized to the Affymetrix GeneChip® Mouse Genome 430 2.0 Array (UCI, Irvine, CA). Grant ID: 5R03HD039421-02 Funding source: Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), National Institutes of Health (NIH) Title: Dorsoventral Patterning in Limb Development Recipient: Kerby C. Oberg