Characterization of the Meis2a Downstream Regulatory Element Dr-m2de1

We have identified four highly conserved noncoding elements associated with the vertebrate Meis2 gene and named them m2de1-4 (for Meis2 downstream element). Using the Tol2 system we have generated transgenic zebrafish in which the zebrafish element (dr-m2de1) has been seen to direct reporter transgene expression the mid and hindbrain of developing embryos.The m2de1 sequence was recently described by another group (Parker et al., 2011), however their data showed dissimilar expression from that of which we have observed. Upon examination of the sequences, we determined that our m2de1 sequence contains an additional 19bp on the 3’ end and an additional 17bp on the 5’. This suggests the possibility that their sequence does not represent the full-length element. In this study I found that that both the Parker paper element and m2de1 both drive broad expression patterns in mid and hindbrain, and that m2de1 also drove expression in the muscle fibers of developing zebrafish while 3288 and any other generated fragment of m2de1 did not. This would appear to suggest that both 3’ and 5’ basepairs not found in 3288 are both necessary for the enhancer to drive complete expression.