CENP-V is required for proper chromosome segregation through interaction with spindle microtubules in mouse oocytes.

Proper chromosome segregation is essential to avoid aneuploidy, yet this process fails with increasing age in mammalian oocytes. Here we report a role for the scarcely described protein CENP-V in oocyte spindle formation and chromosome segregation. We show that depending on the oocyte maturation state, CENP-V localizes to centromeres, to microtubule organizing centers, and to spindle microtubules.

Live cell X-ray imaging of autophagic vacuoles formation and chromatin dynamics in fission yeast.

Seeing physiological processes at the nanoscale in living organisms without labeling is an ultimate goal in life sciences. Using X-ray ptychography, we explored in situ the dynamics of unstained, living fission yeast Schizosaccharomyces pombe cells in natural, aqueous environment at the nanoscale. In contrast to previous X-ray imaging studies on biological matter, in this work the eukaryotic cells were alive even after several ptychographic X-ray scans, which allowed us to visualize the chromatin motion as well as the autophagic cell death induced by the ionizing radiation.

Meiotic Nuclear Oscillations Are Necessary to Avoid Excessive Chromosome Associations.

Pairing of homologous chromosomes is a crucial step in meiosis, which in fission yeast depends on nuclear oscillations. However, how nuclear oscillations help pairing is unknown. Here, we show that homologous loci typically pair when the spindle pole body is at the cell pole and the nucleus is elongated, whereas they unpair when the spindle pole body is in the cell center and the nucleus is round.

Pulled Polymer Loops as a Model for the Alignment of Meiotic Chromosomes.

During recombination, the DNA of parents exchange their genetic information to give rise to a genetically unique offspring. For recombination to occur, homologous chromosomes need to find each other and align with high precision. Fission yeast solves this problem by folding chromosomes in loops and pulling them through the viscous nucleoplasm.

Pivoting of microtubules around the spindle pole accelerates kinetochore capture.

During cell division, spindle microtubules attach to chromosomes through kinetochores, protein complexes on the chromosome. The central question is how microtubules find kinetochores. According to the pioneering idea termed search-and-capture, numerous microtubules grow from a centrosome in all directions and by chance capture kinetochores.

Focal adhesion kinase regulates actin nucleation and neuronal filopodia formation during axonal growth.

The establishment of neural circuits depends on the ability of axonal growth cones to sense their surrounding environment en route to their target. To achieve this, a coordinated rearrangement of cytoskeleton in response to extracellular cues is essential. Although previous studies have identified different chemotropic and adhesion molecules that influence axonal development, the molecular mechanism by which these signals control the cytoskeleton remains poorly understood.

FAK: dynamic integration of guidance signals at the growth cone.

During the formation of neural circuitry, axons are known to be guided to their specific targets by a relatively small arsenal of guidance signals. However, the molecular integration of this guidance information inside the axonal growth cone (GC) is still baffling. Focal adhesion kinase (FAK) is a cytosolic kinase which interacts with a complex molecular network via multiple phosphorylation sites.

Focal adhesion kinase functions downstream of Sema3A signaling during axonal remodeling.

Axon refinement is a necessary event for sculpting the final wiring of neural circuits. Although some factors have been identified that cause axonal arbor remodeling, the molecular pathways transducing these extracellular signals to adhesion disassembly and the cytoskeleton are poorly understood. Here we show that conditional ablation of Focal adhesion kinase (Fak) abolishes axon remodeling induced by Semaphorin-3A (Sema3A) in hippocampal neurons.

Microscopic and transcriptome analyses of early colonization of tomato roots by Trichoderma harzianum.

The capacity of the fungus Trichoderma harzianum CECT 2413 to colonize roots and stimulate plant growth was analyzed. Tobacco seedlings (Nicotiana benthamiana) transferred to Petri dishes inoculated with T. harzianum conidia showed increased plant fresh weight (140%) and foliar area (300%), as well as the proliferation of secondary roots (300%) and true leaves (140%).