Conversely in mink, it has been shown that feeding a low protein diet to the dam reduced the FBP1 mRNA expression in the liver of the offspring. The expression of PCK1, however, was not affected. The latter is in agreement with the present study where a reduced FBP1 protein level and a trend for decreased FBP1 mRNA level was found. Since in mammalian models of prenatal protein undernutrition, differences in gene expression are often found, the mRNA expression of the differential proteins was measured to examine if the same might be true for programming effects in the chicken. Expression of PCK2 and HIBADH, however, was not altered between different groups. The gene expression of FBP1 tended to be numerically lower in the liver of the albumendeprived chicks, compared to a 40% reduction in protein abundance. Most likely, the different abundance in these proteins are regulated via post-transcriptional or post-translational modifications. Finally, the lower embryonic survival of the albumen-deprived chicks compared to both the sham and the control group is in agreement with studies in literature after performance of similar egg manipulations and with our previous results. The reduced survival is the result of an increased early embryonic mortality caused by the manipulation of the egg and inherent to this animal model. Furthermore, if the embryo survived the early stages of the embryonic development, the chance of a successful hatch was the same in the three treatments, as no differences in mid and late death were detected. The four Proteinase-Activated Receptors belong to a superfamily of seven transmembrane, G-protein coupled cell-surface receptors. PARs receive various extracellular signals and mediate them to intracellular responses and play a prominent role in a variety of physiological processes. Activation of PARs occurs usually via proteolytic cleavage of their N-terminal exodomain through extracellular proteases like thrombin. Cleavage creates a new N-terminus that serves as tethered ligand and allows the activation of intracellular signal cascades. PAR1 as the prototype of this group is a high-affinity thrombin receptor and it is therefore critical e.g. in thrombosis, inflammation and angiogenesis. PAR1 can also be activated by MMP-1, a matrix metalloprotease. Absence of Par1 is partially incompatible with embryonic development, since at least half of Par1-deficient mice die around embryonic day E9.5 due to severe bleeding that could be rescued by the introduction of Par1 expression in embryonic endothelial cells. The surviving mice do not exhibit obvious abnormalities. Yue et al. recently demonstrated that Par1 plays a role in the in vitro differentiation of mouse embryonic stem cells into hematopoietic progenitors and in endothelial-to-hematopoietic transition in zebrafish. However, the function of Par1 in adult hematopoiesis has not yet been addressed.