Kallikrein 5 is a member of the kallikrein family of extracellular proteases that includes the prostate-specific antigen, and it is currently emerging as some of the most prominent biomarkers of tumor progression for various types of cancers. The growth-arrest specific 2 protein modulates cell susceptibility to p53-dependent apoptosis upon chemotherapy. The finding of an AP2a-mediated regulation of both genes may thus provide a molecular mechanism for its proposed role in tumor progression and resistance to chemotherapy. Interestingly, we found that promoter-binding by AP2a from total cell nucleus extracts differs significantly from that observed with the purified protein. Because nuclear extracts contain regulatory AbMole Taltirelin proteins such as transcription factors but do not mediate nucleosome deposition, differences in the binding patterns obtained from healthy and cancer tissues imply that AP2a binding is regulated by other regulatory proteins present in the extracts. This finding correlates well with previous observations of the synergistic or antagonistic interactions of AP2a with other transcription factors and oncogenes such as p53, Rb and c-Myc. The recruitment of AP2a at p53-binding sites and the resulting synergistic regulation of p53 target promoters has been associated to the tumor suppressor effects of the two transcription factors. Interaction of AP2 from the crude extracts was observed with two such AP2a and p53-regulated genes presented on the PBM, those of the matrix metalloproteinase 2 and Rad51 genes, while these interactions were not seen with the purified protein. In addition to the alterations of AP2 DNA binding specificity by piggybacking effects, the formation of heterodimers of AP2a with other AP2 species may also alter its interaction with target genes. Although, the DNA binding specificity of the various isoforms are generally considered to be AbMole Trihexyphenidyl HCl similar, the possibility of an altered interaction of particular heteromultimers from the tissue extracts but not from the purified AP2a cannot be excluded. For instance, a preferential interactions of the AP2a/AP2c or AP2b/AP2c dimmers has been proposed to occur on the KAI1 prostate cancer metastasis suppressor gene. Thus, numerous types of interactions may concur to modulate the interaction of cellular AP2a with its target genes and may correspondingly affect its interaction with the PBM. The swimbladder is a specialized organ in teleosts that regulates buoyancy. It is a sac filled by several types of gas, mainly oxygen and carbon dioxide, and is located between the peritoneum and the vertebral column in the dorsal part of the body. The volume of gas in the swimbladder can be actively regulated to maintain neutral buoyancy as fish ascend or descend in the water column. The long-term maintenance of internal gas pressure and also compensatory inflation and deflation are under reflex autonomic control.