The Role Of The Highly Conserved Non-Coding Element M2de1 On The Regulation Of The Expression Of The Meis2 And Zgc:154061 Genes

The Meis genes are members of the three amino acid loop extension (TALE) class, of the homeobox super gene family. Transcription factors encoded by Meis genes act as cofactors with other homeodomain proteins to regulate the expression of target genes during early embryonic development. The Zerucha lab, has identified four highly conserved noncoding elements (m2de1-4) associated with the Meis2 gene that are hypothesized to represent enhancers controlling Meis2 expression. In addition, m2de1 has been found to be in an intron of the zgc:154061 gene. One possible reason for the linkage of the Meis2 and zgc:154061 genes is that they are sharing regulatory elements. I report here that meis2a and zgc:154061 are expressed in a similar pattern as a transgene directed by m2de1. Excision of a region of m2de1 using CRISPR/Cas9 results in decreases in expression of both meis2a and zgc:154061 in these overlapping regions. In addition, knocking down pax6b expression in zebrafish lead to a similar decrease in expression of meis2a and zgc:154061. Together these results suggest that m2de1 is indeed a shared regulatory element controlling meis2a and zgc:154061 expression.