57 research outputs found
Effective stresses and shear failure pressure from in situ Biot's coefficient, Hejre Field, North Sea:Stresses and shear failure pressure
Gγ1, a Downstream Target for the hmgcr-Isoprenoid Biosynthetic Pathway, Is Required for Releasing the Hedgehog Ligand and Directing Germ Cell Migration
The isoprenoid biosynthetic pathway leading from the production of mevalonate by HMGCoA reductase (Hmgcr) to the geranylation of the G protein subunit, Gγ1, plays an important role in cardiac development in the fly. Hmgcr has also been implicated in the release of the signaling molecule Hedgehog (Hh) from hh expressing cells and in the production of an attractant that directs primordial germ cells to migrate to the somatic gonadal precursor cells (SGPs). The studies reported here indicate that this same hmgcr→Gγ1 pathway provides a novel post-translational mechanism for modulating the range and activity of the Hh signal produced by hh expressing cells. We show that, like hmgcr, gγ1 and quemao (which encodes the enzyme, geranylgeranyl diphosphate synthetase, that produces the substrate for geranylation of Gγ1) are components of the hh signaling pathway and are required for the efficient release of the Hh ligand from hh expressing cells. We also show that the hmgcr→Gγ1 pathway is linked to production of the germ cell attractant by the SGPs through its ability to enhance the potency of the Hh signal. We show that germ cell migration is disrupted by the loss or gain of gγ1 activity, by trans-heterozygous combinations between gγ1 and either hmgcr or hh mutations, and by ectopic expression of dominant negative Gγ1 proteins that cannot be geranylated
A multidisciplinary approach to investigate the osteobiography of the Roman Imperial population from Muracciola Torresina (Palestrina, Rome, Italy)
The present research provides the osteobiographical reconstruction of the Roman Imperial population of the rural area of Muracciola Torresina (Palestrina, Rome, Italy) through an innovative multidisciplinary approach, combining evidence from skeletal biology, biomolecules and archaeobotany. The excavation of the site, unearthed 76 individuals: 84.2% adults and 15.8% non-adults. Morphological examination showed a higher prevalence of females with respect to males (M:F = 0.89). Musculoskeletal stress marker analysis highlighted a probable division of daily tasks between sexes; the observed modifications mainly affected the upper limbs with a particular involvement of shoulder and elbow joints. The population seems to have experienced physically strenuous life conditions, as suggested by the high frequency of degenerative and infectious diseases. Carbon and nitrogen stable isotope data supported an omnivorous diet mainly based on C3 plants and terrestrial animal protein. No statistically significant difference was found between sexes or age classes, even though a discrete variability of nitrogen isotopic values was observed which was hypothesized to reflect the consumption of pulses by certain individuals with the lowest values. Microscopic analysis of dental calculus detected Triticeae starch granules in the majority of the analyzed individuals. Chromatographic profiles additionally revealed the presence of ephedrine derivatives in the calculus of two individuals, an alkaloid which might indicate the consumption of Ephedra species used as medicinal plant due to its bronchodilator, nasal decongestant and vasoconstrictor properties. This use of multiple cutting-edge techniques has revealed a detailed snapshot of the diet and lifeways of the first Roman Imperial population to be recovered from the area of ancient Praeneste
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