Of mice and ... snakes
Vertebrates exhibit a remarkable variation in trunk and tail lengths. However, how this diversity comes about is mostly unknown. Rita Aires et al. report in Developmental Cell that Oct4 is a key regulator of vertebrate trunk length diversity. They show that snake embryos express Oct4 for longer periods than mouse embryos and provide evidence to suggest that differential genomic rearrangements of noncoding regions near the Oct4 locus may underlie this phenomenon in snakes. Also see Latest News in Science.
Fetal heart ECM shows enhanced potential to support cardiac cells.
A main challenge in cardiac tissue engineering is the limited data on microenvironmental cues that sustain survival, proliferation and functional proficiency of cardiac cells. The group of Microenvironments for New Therapies at i3S at University of Porto, addressed this issue by comparing the potential of fetal (E18) and adult myocardial extracellular matrix (ECM) to support cardiac cells. Their findings, in an article by Ana Silva et al entitled “Three-dimensional scaffolds of fetal decellularized hearts exhibit enhanced potential to support cardiac cells in comparison to the adult” published in Biomaterials, demonstrate the superior potential of the 3D fetal microenvironment to support and instruct cardiac cells. This knowledge should be integrated in the design of next-generation biomimetic materials for heart repair.
Review on Drosophila imaginal discs
Jorge Beira and Renato Paro publish a review entitled "The legacy of Drosophila imaginal discs". The study of Drosophila imaginal discs has contributed to a number of discoveries in developmental and cellular biology and have become established models for studying cellular interactions and complex genetic pathways. This comprehensive review article revisits older and highlights new studies using this fantastic developmental model.
Dilp8–Lgr3 critical to ensure developmental stability in Drosophila
The group of Alisson Gontijo at CEDOC discovered a novel neuroendocrine circuit responsive to growth aberrations. Different organs need to sense growth perturbations in distant tissues to coordinate their size and differentiation status during development. The Gontijo team determined that the sensing of peripheral growth perturbations in the fruit fly (Drosophila melanogaster) requires a novel population of CNS neurons expressing the Lgr3 relaxin receptor. Neuronal Lgr3 is required for the transmission of the peripheral growth aberration signal, Dilp8, to the prothoracic gland, which controls the onset of metamorphosis and thereby the cessation of imaginal disc growth. This work reveals a new Dilp8–Lgr3 pathway that is critical to ensure developmental stability in Drosophila. See the paper here.
aECM to F-actin feedback mechanism
Sofia Araújo and collaborators discovered an apical ECM to F-actin feedback mechanisms in tracheal cells which was recently published in eLife. The authors show that there is an active feedback mechanism between apical ECM (aECM) and the apical F-actin in tracheal cells. Cell-cell junctions are shown to be key players in this aECM patterning and organisation and that individual cells contribute autonomously to their aECM. Strikingly, changes in the aECM influence the levels of phosphorylated Src42A (pSrc) at cell junctions. The authors propose that Src42A phosphorylation levels provide a link for the extracellular matrix environment to ensure proper cytoskeletal organisation. See paper here.