There's more than one way to scale a synapse

TNFalpha has been proposed to underlie synaptic scaling, but the mechanism and functional significance of this remain unclear. In this issue of Neuron, Cingolani et al. demonstrate that TNFalpha can mediate scaling through the regulation of beta3 integrins. Kaneko et al. show that TNFalpha-dependent synaptic scaling plays an important role in visual cortical plasticity.     

A20: more than one way to skin a cat

In this issue of Molecular Cell, Skaug et al. (2011) propose a polyubiquitin-dependent, noncatalytic mechanism by which the deubiquitinase A20 inhibits IκB kinase and NF-κB activation.     

Left-right asymmetry: more than one way to coil a shell

Snail shells can be left-handed or right-handed, sometimes within one species. For over a century, it has commonly been assumed that mirror-image shell coiling in snails is correlated with a mirror- image reversal of early spindle orientation and cleavage. The results of an exciting and elegant new study refute this model, showing that right doesn't have to be the mirror image of left.     

Virus membrane-fusion proteins: more than one way to make a hairpin

Structure-function studies have defined two classes of viral membrane-fusion proteins that have radically different architectures but adopt a similar overall 'hairpin' conformation to induce fusion of the viral and cellular membranes and therefore initiate infection. In both classes, the hairpin conformation is achieved after a conformational change is triggered by interaction with the target cell. This review will focus in particular on the properties of the more recently described class II proteins.     

ER export: more than one way out

Protein export from the ER is mediated by COPII vesicles. Glycosylphosphatidylinositol-linked proteins seem to be segregated from other cargo proteins during ER export, suggesting that ER membranes produce more than one type of vesicle.     

There is more than one way to skin a G matrix

Because of its importance in directing evolutionary trajectories, there has been considerable interest in comparing variation among genetic variance-covariance (G) matrices. Numerous statistical approaches have been suggested but no general analysis of the relationship among these methods has previously been published. In this study, we used data from a half-sib experiment and simulations to explore the results of applying eight tests (T method, modified Mantel test, Bartlett's test, Flury hierarchy, jackknife-manova, jackknife-eigenvalue test, random skewers, selection skewers). Whereas a randomization approach produced acceptable estimates, those from a bootstrap were typically unacceptable and we recommend randomization as the preferred method. All methods except the jackknife-eigenvalue test gave similar results although a fine-scale analysis suggested that the former group can be subdivided into two or possibly three groups, hierarchical tests, skewers and the rest (jackknife-manova, modified Mantel, T method, probably Bartlett's). An advantage of the jackknife methods is that they permit tests of association with other factors, such as in this case, temperature and sex. We recommend applying all the tests described in this article, with the exception of the T method, and provide R functions for this purpose.     

Cytokinesis in flowering plants: cellular process and developmental integration

In phragmoplast-assisted cytokinesis of somatic cells, vesicle fusion generates a cell plate that matures into a new cell wall and its flanking plasma membranes. Insight into this dynamic process has been gained in the past few years and additional molecular components of the basic machinery of cytokinesis have been identified. Specialized modes of cytokinesis occur in meiosis and gametophyte development, and recent studies indicate that they are genetically distinct from somatic cytokinesis.     

Asymmetric cell division: a new way to divide unequally

It has long been known that cells can divide unequally by shifting the mitotic spindle to one side. Two recent reports identify an alternative way to generate daughter cells of different sizes.