Volume 17 Issue 5, May 2015

How proteins migrate through the interconnected organelles of the endolysosomal system is poorly understood. A piece of the puzzle has been added with the identification of a complex of tethering factors that functions in the recycling of proteins towards the cell surface.

Whether the cancer cells responsible for the growth of primary tumours are also able to re-initiate tumour growth after seeding to distant organs is unclear. The characterization of breast cancer cells with both of these attributes now identifies the functional and molecular determinants necessary to mediate primary tumour formation and re-initiation at the secondary site.

Mostoslavsky and colleagues reveal that in embryonic stem cells (ESC) the deacetylase SIRT6 regulates pluripotency genes, which in turn controls ESC differentiation though the activity of Tet enzymes.

Gavis and colleagues characterize RNP trafficking and assembly using quantitative single-molecule imaging and find mRNAs destined for the germ cells are assembled differently from oskar, the germline determinant mRNA.

Hopyan and colleagues show that tension in the mesoderm and ectoderm leads to formation of a stress pattern that drives the rearrangements of ectodermal cells during limb bud morphogenesis in mouse embryos.

Keller and colleagues show that haemogenic and vascular endothelium represent distinct lineages and that haemogenic endothelium gives rise to multipotent haematopoietic progenitors through a NOTCH-dependent endothelial-to-haematopoietic transition.

Fuchs and colleagues report a role for the F-actin binding protein Wdr1 in the establishment of planar polarity in the mouse embryonic epidermis by mediating tension.

Using large-volume correlative electron tomography, Brunner and colleagues show that microtubules provide forces for the sealing of the epidermis during dorsal closure in Drosophila.

By deciphering the transcriptional network of human embryonic pancreatic progenitors, Ferrer and colleagues identify the Hippo-responsive transcription factor TEAD1 as a regulator of the pancreatic progenitor enhancer programme.

Tzahor and colleagues show that ErbB2 signalling is required for cardiomyocyte proliferation in fetal and postnatal mouse hearts, and that its activation in adult hearts promotes cardiomyocyte proliferation and regeneration following myocardial ischaemic injury.

Bonifacino and colleagues identify a four-protein complex, called the endosome-associated recycling protein (EARP) complex, that associates with Rab4-positive endosomes and promotes recycling-endosome tethering and fusion.

Using in vivo tumour-cell selection approaches Tavazoie and colleagues identify LAMA4 among the factors that enhance tumour-forming capacity and metastatic efficiency to promote primary and metastatic tumour re-initiation.

Zhang and colleagues show that the ITIM-containing receptor LAIR1 supports self-renewal and survival of acute myeloid leukaemia stem cells through a signalling pathway that includes the SHP-1 phosphatase, CAMK1 kinase and CREB transcription factor.

Yang and colleagues report that increased extracellular matrix stiffness promotes nuclear localization of Twist1 to drive epithelial–mesenchymal transition, cancer cell invasion and metastasis.

Lehmann and colleagues describe a role for the ATP synthase in Drosophila germline stem cell differentiation that is independent of ATP synthesis, and involves the maturation of mitochondrial cristae.

Using C. elegans zygotes, Dumont and colleagues find that kinetochore proteins, including KNL-1, participate in assembly of central spindle microtubules for cytokinesis.