Thus, some of the existent non-coding DNA may have a connection with maintaining optimal regulation of gene expression after a WGD, as previously proposed in a different context. Transformation of coding regions into non expressed pseudogenes and allowing selfish DNA proliferation might help stabilize the nuclear/cellular volume and thus, the functioning of cellular circuits and pathways. According to this scenario,Navitoclax non-functionalized genes and selfish DNA are obviously not completely devoid of function. Another outstanding biophysical effect of non-coding DNA that cannot be overlooked in a WGD process involves protein-DNA interactions. DNA binding proteins may recognize sequences that are similar to their real target sites giving rise to non-specific interactions. This is obvious for proteins such as basic-HLH and leucine zipper-containing factors that have a basic DNA-binding domain, allowing non-specific electrostatic interac-tions with DNA. Given the size of eukaryotic genomes, the amount of DNA available for non-specific interactions is enormous with respect to the specific binding sites for a particular factor. For simplicity, we disregard potential differences in the contribution of euchromatin and heterochromatin to non-specific binding. The existence of a substantial amount of non-specific interactions is likely to pose a problem when genomic DNA is deleted and not replaced. This can be explored by the analysis of the binding of a transcription factor,SJN 2511 TF, to specific and non-specific sites. In the context of a recently formed tetraploid, let us consider a TF that specifically recognizes a few binding sites/ nucleus. Specific recognition will take place with high affinity while non-specific recognition will normally take place with much lower affinity. The concentration of irrelevant DNA binding sites can be several orders of magnitude higher, which can easily be the case in plant genomes, because each short sequence is in principle a non-specific binding site.