Discussion

• Cux2 is a transcription factor containing four well conserved DNA-binding domains, three Cut domains and one Homeodomain. To excert its function it could be blocking the DNA from other factors, or interacting with other proteins through still unknown domains.

• Cux2 itself is regulated by other transcription factors. There is very little evidence of alternative splicing.

• Cux2 is mainly expressed in different compartments of the brain, and to some extent liver and prostate.

• There might be miRNA target sites in Cux2, but the evidence is minimal. However, if hsa-miR-216 is a bonafide miRNA against Cux2, then it might be regulating other genes as well that are somehow important for the development or function of the fetal liver, olfactory bulb or kidney.

• Two suggested direct targets of Cux2 expression, Neurod1 and P27 Kip1 both have CCAAT response elements in their promoter regions.

• There are four different SNP in the Cux2 locus, only one of them is in a conserved region (rs6490073) and more importantly it is in the coding region of Cux2. However, it remains to be resolved what the most common nucleotide is on the position of this SNP, since there is conflicting data from other mammalian species. The SNP will probably not affect the protein function of Cux2.