FoxH1 (Fast1) was first characterized as the transcriptional partner for Smad proteins. Together with Smad2/4, it forms the activin response factor(ARF) that binds to the Mix.2 promoter in Xenopus embryos. Foxh1 is expressed maternally in Xenopus. Depletion of maternal Foxh1 mRNA results in abnormalities of head and dorsal axis formation. We show that FoxH1 is required, together with XTcf3/β catenin,to activate the zygotic expression of the nodal gene, Xnr3 in a Smad2-independent manner. In contrast, maternal FoxH1 acts as an inhibitor of Xnr5 and 6 transcription, preventing their upregulation on the ventral side of the embryo, by the maternal T-box transcription factor VegT. We conclude that maternal FoxH1 has essential, context-dependent roles in regulating the pattern of zygotic gene expression in the early embryo.

Wnt signaling pathways have essential roles in developing embryos and adult tissue, and alterations in their function are implicated in many disease processes including cancers. The major nuclear transducers of Wnt signals are the Tcf/LEF family of transcription factors, which have binding sites for both the transcriptional co-repressor groucho, and the co-activator beta-catenin. The early Xenopus embryo expresses three maternally inherited Tcf/LEF mRNAs, and their relative roles in regulating the expression of Wnt target genes are not understood. We have addressed this by using antisense oligonucleotides to deplete maternal XTcf1 and XTcf4 mRNAs in oocytes. We find that XTcf1 represses expression of Wnt target genes ventrally and laterally, and activates their expression dorsally. Double depletions of XTcf1 and XTcf3 suggest that they act cooperatively to repress Wnt target genes ventrally. In contrast, XTcf4 has no repressive role but is required to activate expression of Xnr3 and chordin in organizer cells at the gastrula stage. This work provides evidence for distinct roles for XTcfs in regulating Wnt target gene expression.

Although there have been many studies reporting the attitudes of medical students to the clinical importance of gross anatomy, little is known about their opinions concerning the clinical importance of embryology. Using Thurstone and Chave methods to assess attitudes, nearly 1,600 medical students across Europe in the early stages of their training provided responses to a survey that tested the hypothesis that they do not regard embryology as highly clinically relevant. Indeed, we further proposed that student attitudes to gross anatomy are much more positive than those toward embryology. Our findings show that our hypotheses hold, regardless of the university and country surveyed and regardless of the teaching methods employed for embryology. Clearly, embryology has a significant part to play in medical education in terms of understanding prenatal life, of appreciating how the organization of the mature human body has developed, and of providing essential information for general medical practice, obstetrics and pediatrics, and teratology. However, while newly recruited medical students understand the importance of gross anatomy in the development of professional competence, understanding the importance of embryology requires teachers, medical educationalists, and devisors of medical curricula to pay special attention to informing students of the significant role played by embryology in attaining clinical competence and achieving the knowledge and understanding of the biomedical sciences that underpins becoming a learned member of a health care profession.

Internationalization has commanded an ever-more prominent position in higher education over recent years, and is now firmly entrenched. While academia has long been outward looking-international research collaborations, conferences and student exchanges are well-established practices-it is relatively recently that internationalization has become a goal in its own right, rather than a consequence of normal academic activity. There are multiple interdependent drivers behind this: a focus on graduate employability and development of broad competencies and transferable skills in addition to subject-specific training, 'international awareness' being confirmed as a graduate attribute that is highly valued by employers, the availability of detailed information enabling prospective students to choose between Higher Education Institutions on the basis of their international opportunities and graduate employment rates, increasing competition between Institutions to attract the best students and to ascend national and international league tables, and (both driving and reflecting these trends) national policy frameworks. This minireview focuses on two aspects of internationalization of direct relevance to microbiology students and academic staff in a typical Higher Education Institution: student research placements overseas, and the impact of international mobility on teaching practice and the student experience. Practical strategies for developing intercultural awareness and enhancing employability are highlighted.

The Wingless (Wg)/Wnt signal transduction pathway regulates many developmental processes through a complex of Armadillo(Arm)/β-catenin and the HMG-box transcription factors of the Tcf family. We report the identification of a new component, Pygopus (Pygo), that plays an essential role in the Wg/Wnt signal transduction pathway. We show that Wg signaling is diminished during embryogenesis and imaginal disc development in the absence of pygo activity. Pygo acts downstream or in parallel with Arm to regulate the nuclear function of Arm protein. pygo encodes a novel and evolutionarily conserved nuclear protein bearing a PHD finger that is essential for its activity. We further show that Pygo can form a complex with Arm in vivo and possesses a transcription activation domain(s). Finally, we have isolated a Xenopus homolog of pygo (Xpygo). Depletion of maternal Xpygo by antisense deoxyoligonucleotides leads to ventralized embryonic defects and a reduction of the expression of Wnt target genes. Together, these findings demonstrate that Pygo is an essential component in the Wg/Wnt signal transduction pathway and is likely to act as a transcription co-activator required for the nuclear function of Arm/β-catenin.