Characterizing endocrine and transcriptional determinants of P utilization mediated by the environment-host-microbiota interaction in laying hens and quails

该项目研究了饲料×微生物组×宿主复杂相互作用中的宿主转录组和内分泌表型，这些表型影响蛋鸡和鹌鹑的肠道植酸盐（InsP6）降解、磷酸肌醇（InsPx）模式、肌醇水平和磷（P）利用。影响肠内植酸酶活性和InsPx代谢的可变P供应引起内分泌、旁分泌和自分泌调节P稳态的适应性反应，这也反映在转录组水平上。这些反应是由于饲料和饲料中发现的P、InsPx和肌醇的可用性以及微生物群组成变化的间接影响。此外，在P利用存在相当大的变化，物种之间和内部突出遗传和潜在的遗传变异。基于本研究单元项目1中描述的饲养实验和项目2中描述的育种实验的综合表型和基因型记录，我们计划对肠道样品进行整体表达分析，以鉴定由于P利用的表型差异而发生转移的基因和分子途径，可变矿物质钙和磷补充剂和个体发育从开始和在产蛋期在两个蛋鸡品系。在每种情况下，将记录对实验改变的内分泌反应，并分析内分泌和转录组反应之间的关系。该项目将提供深入了解参与肠道维持P稳态的分子途径。内分泌和旁分泌调节途径将与代表复杂饮食×微生物组×宿主相互作用的宿主部分的分子内表型一起沿着阐明。这些数据将在本研究单位的其他项目中收集的大量信息的背景下进行分析和解释，这些信息涉及影响肠道InsP6降解，InsPx模式，肌醇水平和P利用的宿主和微生物机制。

The project addresses the host transcriptomic and endocrine endo-phenotypes in the complex interaction of diet × microbiome × host that affect intestinal phytate (InsP6) degradation, inositol phosphate (InsPx) pattern, myo-inositol levels, and phosphorus (P) utilization in laying hens and quails. Variable P supply affecting enteral phytase activity and the metabolism of InsPx provokes adaptive responses of the endocrine, paracrine, and autocrine regulation of P homeostasis that are mirrored also at the transcriptome level. These responses result from the availability of P, InsPx, and myo-inositol found in the feedstuff and digesta as well as the indirect effects of changes in microbiota composition. Furthermore, considerable variation in P utilization exists among and within species highlighting heritability and underlying genetic variation. Based on comprehensive phenotypic and genotypic records of the feeding experiments described in Project 1 and of the breeding experiment described in Project 2 of this Research Unit, we plan holistic expression analyses of gut samples in order to identify genes and molecular pathways that are shifted due to phenotypic divergence in P utilization, variable mineral Ca and P supplements and ontogenetic development from the onset and during the laying period in two laying hen strains. In each of these conditions, the endocrine response to experimental alterations will be recorded and the relationship among endocrine and transcriptomic responses analyzed. This project will provide insight into the molecular routes engaged in the gut to maintain P homeostasis. Endocrine and paracrine regulatory pathways will be elucidated along with the molecular endo-phenotypes that represent the host part of the complex diet × microbiome × host interaction. The data will be analysed and interpreted at the background of the vast amount of information gathered in the other projects of this Research Unit about the host- and the microbiota-mechanisms affecting the intestinal InsP6 degradation, InsPx pattern, myo-inositol levels, and P utilization.