The Peroxisomal 3-keto-acyl-CoA thiolase B Gene Expression Is under the Dual Control of PPARα and HNF4α in the Liver

PPARα and HNF4α are nuclear receptors that control gene transcription by direct binding to specific nucleotide sequences. Using transgenic mice deficient for either PPARα or HNF4α, we show that the expression of the peroxisomal 3-keto-acyl-CoA thiolase B (Thb) is under the dependence of these two transcription factors. Transactivation and gel shift experiments identified a novel PPAR response element within intron 3 of the Thb gene, by which PPARα but not HNF4α transactivates. Intriguingly, we found that HNF4α enhanced PPARα/RXRα transactivation from TB PPRE3 in a DNA-binding independent manner. Coimmunoprecipitation assays supported the hypothesis that HNF4α was physically interacting with RXRα. RT-PCR performed with RNA from liver-specific HNF4α-null mice confirmed the involvement of HNF4α in the PPARα-regulated induction of Thb by Wy14,643. Overall, we conclude that HNF4α enhances the PPARα-mediated activation of Thb gene expression in part through interaction with the obligate PPARα partner, RXRα

Creating Conditions for Harnessing the Potential of Transitions to Agroecology in Europe and Requirements for Policy

Food systems require reorientation to take greater account of interactions with the environment, economy, health and society. Transitions to agroecological farming practices and systems can connect policy areas and realise environmental, economic and social aims. These transitions provide a lens for reviewing policy, practice and behaviours of actors in farming systems and value chains, identification of barriers to uptake, and policy areas to which they contribute or where there are gaps. Developing social and human capital, and governance structures that enable transitions to agroecology are key to their prospects of success. Education and life-long learning are key to developing the knowledge and skills of younger generations of land managers and other actors in value chains, throughout their careers. The outcome sought is for a shared understanding of the benefits of agroecological practices and systems, creating opportunities to rebalance policies towards delivering climate neutrality, reversing biodiversity loss, and enhancing rights of citizens. To realise those opportunities policies and strategies should be coherent across territorial and systems levels, and tailored to place, system, people, and stages of transitions. Overall, they should be designed to ensure all citizens are beneficiaries of transitions to agroecological farming systems, over the long term, and that no-one or place is disadvantaged by the processes of change or the outcome intended