University of Nice Sophia Antipolis

About: University of Nice Sophia Antipolis is a education organization based out in Nice, France. It is known for research contribution in the topics: Population & Stars. The organization has 10291 authors who have published 19964 publications receiving 680762 citations. The organization is also known as: UNS & University of Nice-Sophia Antipolis.

The hypoxia-inducible-factor hydroxylases bring fresh air into hypoxia signalling

Abstract: Metazoans rapidly respond to changes in oxygen availability by regulating gene expression. The transcription factor hypoxia-inducible-factor (HIF), which controls the expression of several genes, ‘senses' the oxygen concentration indirectly through the hydroxylation of two proline residues that earmarks the HIF-α subunits for proteasomal degradation. We review the expression, regulation and function of the HIF prolyl hydroxylases or prolyl hydroxylases domain proteins, which are genuine oxygen sensors.

Principles and roles of mRNA localization in animal development

Abstract: Intracellular targeting of mRNAs has long been recognized as a means to produce proteins locally, but has only recently emerged as a prevalent mechanism used by a wide variety of polarized cell types. Localization of mRNA molecules within the cytoplasm provides a basis for cell polarization, thus underlying developmental processes such as asymmetric cell division, cell migration, neuronal maturation and embryonic patterning. In this review, we describe and discuss recent advances in our understanding of both the regulation and functions of RNA localization during animal development.

Oncogenicity of the Developmental Transcription Factor Sox9

Abstract: SOX9 [sex-determining region Y (SRY)-box 9 protein], a high mobility group box transcription factor, plays critical roles during embryogenesis and its activity is required for development, differentiation, and lineage commitment in various tissues including the intestinal epithelium. Here, we present functional and clinical data of a broadly important role for SOX9 in tumorigenesis. SOX9 was overexpressed in a wide range of human cancers, where its expression correlated with malignant character and progression. Gain of SOX9 copy number is detected in some primary colorectal cancers. SOX9 exhibited several pro-oncogenic properties, including the ability to promote proliferation, inhibit senescence, and collaborate with other oncogenes in neoplastic transformation. In primary mouse embryo fibroblasts and colorectal cancer cells, SOX9 expression facilitated tumor growth and progression whereas its inactivation reduced tumorigenicity. Mechanistically, we have found that Sox9 directly binds and activates the promoter of the polycomb Bmi1, whose upregulation represses the tumor suppressor Ink4a/Arf locus. In agreement with this, human colorectal cancers showed a positive correlation between expression levels of SOX9 and BMI1 and a negative correlation between SOX9 and ARF in clinical samples. Taken together, our findings provide direct mechanistic evidence of the involvement of SOX9 in neoplastic pathobiology, particularly, in colorectal cancer.

Images of Asteroid 21 Lutetia: A Remnant Planetesimal from the Early Solar System

Abstract: Images obtained by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) cameras onboard the Rosetta spacecraft reveal that asteroid 21 Lutetia has a complex geology and one of the highest asteroid densities measured so far, 3.4 ± 0.3 grams per cubic centimeter. The north pole region is covered by a thick layer of regolith, which is seen to flow in major landslides associated with albedo variation. Its geologically complex surface, ancient surface age, and high density suggest that Lutetia is most likely a primordial planetesimal. This contrasts with smaller asteroids visited by previous spacecraft, which are probably shattered bodies, fragments of larger parents, or reaccumulated rubble piles.

Type ID unconventional myosin controls left–right asymmetry in Drosophila

Abstract: From flies to humans, the left and right side of the body plan differs. Exactly how symmetry is broken in the early embryo is a mystery. But now two groups working independently report a genetic defect in the fly that may help uncover the mechanism. Both groups studied a mutant with reversed looping of the viscera, and discovered that the mutation lies in an unconventional myosin. Myosin directs right-handed looping and represses the default left-handed fate. This discovery now links actin-based molecular motors and the actin cytoskeleton to left–right patterning in vertebrates. One of a pair of papers separately showing that an unconventional myosin directs handedness of the viscera of Drosophila. Breaking left–right symmetry in Bilateria embryos is a major event in body plan organization that leads to polarized adult morphology, directional organ looping, and heart and brain function1,2,3,4. However, the molecular nature of the determinant(s) responsible for the invariant orientation of the left–right axis (situs choice) remains largely unknown. Mutations producing a complete reversal of left–right asymmetry (situs inversus) are instrumental for identifying mechanisms controlling handedness, yet only one such mutation has been found in mice (inversin)5 and snails6,7. Here we identify the conserved type ID unconventional myosin 31DF gene (Myo31DF) as a unique situs inversus locus in Drosophila. Myo31DF mutations reverse the dextral looping of genitalia, a prominent left–right marker in adult flies. Genetic mosaic analysis pinpoints the A8 segment of the genital disc as a left–right organizer and reveals an anterior–posterior compartmentalization of Myo31DF function that directs dextral development and represses a sinistral default state. As expected of a determinant, Myo31DF has a trigger-like function and is expressed symmetrically in the organizer, and its symmetrical overexpression does not impair left–right asymmetry. Thus Myo31DF is a dextral gene with actin-based motor activity controlling situs choice. Like mouse inversin8, Myo31DF interacts and colocalizes with β-catenin, suggesting that situs inversus genes can direct left–right development through the adherens junction.