Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
There is a lack of trained scientists to fill the increasing number of jobs and funding opportunities in the Indian scientific research sector. This is a great opportunity for the international scientific community to help build and nurture a vibrant cell biology research community in India.
The establishment and maintenance of cell polarity requires targeted recruitment of polarity regulators to the plasma membrane. Phosphatidylserine is now shown to have a key role in polarization of yeast cells and the localization of the central polarity regulator Cdc42.
In mitotic spindles, each sister chromatid is directly attached to a spindle pole through microtubule bundles known as kinetochore fibres. Microspherule protein 1 (MCRS1) is now shown to support spindle assembly by localizing to the minus ends of kinetochore fibres and protecting them from depolymerization.
To establish and maintain their internal organization, living cells must move molecules to their correct locations. Long-range intracellular movements are often driven by motor molecules moving along microtubules, similarly to trucks driving along a highway. Recent work demonstrates that some randomly dispersed cargos can generate actin filaments that form a connected network whose contraction drives collective cargo movement.
The transcriptional role of c-Myc in maintaining tissue homeostasis is still unclear. Using mice conditionally expressing an activated form of c-Myc in the epidermis, and genome-wide approaches, Frye and colleagues show that c-Myc modulates the expression of the epidermal differentiation complex locus in the skin by displacing or recruiting specific transcriptional regulators. c-Myc activity is negatively regulated in vivo in this context by Sin3a.
Chromosomal microtubules participate in formation of kinetochore fibres by attaching their plus ends at kinetochores and focusing their minus ends at the spindle poles. Vernos and colleagues show that the centrosome-localized protein MCRS1 accumulates to chromosomal microtubule minus ends in a RanGTP-dependent manner to prevent microtubule depolymerization and to promote kinetochore-fibre stability and spindle assembly.
Wallerian degeneration occurs in axons following cutting or crush injuries; however, the molecular mechanisms that regulate this process remain elusive. Araki and colleagues find that the ubiquitin ligase ZNRF1 promotes Wallerian degeneration by ubiquitylating AKT, which leads to increased GSK3B activity and subsequent inhibition of the tubulin-binding protein CRMP2.
In yeast, polarized localization of Cdc42 is essential for budding and mating, but how polarity is attained has been elusive. Grinstein and colleagues show that phosphatidylserine accumulates in a polar fashion in yeast, and is required for the proper localization of Cdc42.
In mammalian cells, long-range vesicular transport is thought to occur via microtubule tracks. However, Schuh reports the existence of an actin-based pathway for long-range trafficking in mouse oocytes by showing that Rab11a-positive vesicles are decorated with actin-nucleating formin proteins. She finds that these proteins assemble actin networks that guide vesicles to the cell surface.
Caspase 8 is known to suppress necroptosis, but its relevant target protein was unknown. Ting and colleagues show that caspase 8 cleaves the deubiquitylase CYLD to inhibit necroptosis and promote cell survival.
The MYC proto-oncogene modulates transcription through binding to E-boxes. Di Croce and colleagues find that PAK-2-mediated phosphorylation confers a tumour-suppressive function to MYC, in which MYC cooperates with differentiation signals to positively modulate the transcription of genes targeted by retinoic acid, independently of E-boxes.
Aragón and colleagues show that the phosphatase Cdc14 acts on the CDT subunit of RNA polymerase II to silence transcription of repetitive regions of the yeast genome. At telomeres this event promotes condensin loading and mitotic segregation.
Bershadsky and colleagues show that fibroblast polarization depends on matrix rigidity and focal adhesion mechanosensing. They target protein tyrosine kinases through RNAi to identify signalling molecules that regulate traction force generation, focal adhesion assembly and mechanosensitivity.
