Volume 11 Issue 6, June 2009

Author contribution statements are now mandatory and author responsibilities have been clarified.

Nature Cell Biology will publish online methods in more detail.

Stem cells achieve the remarkable task of generating both identical copies of themselves and lineage-restricted daughter cells that ultimately undergo terminal differentiation. The differential regulation of ribosomal protein biosynthesis helps to generate these two outcomes in Drosophila melanogaster.

Eighty years of microscopy have established a conventional view of nuclear organization: dark-staining heterochromatin at the nuclear periphery and light-staining euchromatin in the interior. This nuclear architecture is inverted in rod cells of nocturnal mammals, demonstrating a unique functional nuclear genome reorganization specifically adapted for light transmission.

Local regulation of protein translation is essential for synaptic plasticity. MicroRNA-mediated alteration in expression of an enzyme that regulates the palmitoylation of a specific synaptic protein determines dendritic spine size.

It is unclear how the growth rate and size of asymmetrically dividing stem cells are regulated. The U3snoRNP component Wicked, required for pre-ribosomal RNA maturation and thus ribosome formation, is localized asymmetrically and is critical for stem cell maintenance and function.

The tumour suppressor p53 inhibits cancer cell proliferation and induces apoptosis. A new tumour-suppressive effect of p53 is to induce MDM2-dependent degradation of the tumour invasion factor Slug, resulting in reduced metastasis.

Mir-138, identified in a screen for microRNAs associated with synapses, regulates dendritic spine morphogenesis through APT-1, a depalmitoylation enzyme that modulates the membrane localization of the heterotrimeric G protein alpha subunit.

Kinesin-14 (Ncd in Drosophila, and Klp2 in fission yeast) is a microtubule-based motor important for spindle assembly. Ncd and Klp2 mediate both sliding of anti-parallel microtubules and crosslinking of parallel ones.

Kinesin-14 (Ncd in Drosophila, and Klp2 in fission yeast) is a microtubule-based motor important for spindle assembly. Ncd and Klp2 mediate both sliding of anti-parallel microtubules and crosslinking of parallel ones.

Arabidopsis root-hair position and orientation in epithelial cells is directed by an auxin gradient maximum at the root tip. The Raf-like kinase CTR1 negatively regulates local auxin biosynthesis in the root to determine root hair position.

Shh acts as a survival factor and in its absence its receptor, Patched, induces cell death by recruiting a caspase-activating complex formed by the adaptor protein DRAL, the CARD domain containing proteins TUCAN or NALP1, and caspase-9.

The glycolytic enzyme Pfkfb3 is shown to be constitutively ubiquitylated by the APC/C ligase and degraded in neurons. These findings might explain the lower glycolytic metabolism in these cells relative to astrocytes.

The FANC and the BLM pathways collaborate during mitosis to prevent micronucleation and chromosome abnormalities.

The FANC and the BLM pathways collaborate during mitosis to prevent micronucleation and chromosome abnormalities.

Mutations in the MIP phosphatase MTMR14 are associated with human autosomal centronuclear myopathy. Mice that lack MIP have impaired muscle performance and enhanced fatigue due to the accumulation of MIP substrates PtdIns(3,5)P2 and PtdIns(3,4)P2, which cause alterations in intracellular Ca2+ levels.

In keratinocytes, the multifunctional protein CLIC4 mediates TGF-β-dependent growth inhibition through interaction with Schnurri-2, which is essential for CLIC4 nuclear translocation. Once in the nucleus, CLIC4 associates with phospho-Smad2 and 3 and protects them from dephosphorylation by nuclear phosphatases.