Soluble low-molecular-mass protein isoforms were purified from chemosensory organs (antennae, tarsi and labrum) of the desert locust Schistocerca gregaria. Five genes encoding proteins of this group were amplified by PCR from cDNAs of tarsi and sequenced. Their expression products are polypeptide chains of 109 amino acids showing 40±50% sequence identity with putative olfactory proteins from Drosophila melanogaster and Cactoblastis cactorum. Direct structural investigation on isoforms purified from chemosensory organs revealed the presence in the expression products of two of the genes cloned. Two additional protein isoforms were detected and their molecular structure exhaustively characterized. MS analysis of all isoforms demonstrated that the four cysteine residues conserved in the polypeptide chain were involved in disulfide bridges (Cys29±Cys38 and Cys57±Cys60) and indicated the absence of any additional post-translational modifications. Immunocytochemistry experiments, performed with rabbit antiserum raised against the protein isoform mixture, showed selective labelling of the outer lymph in contact sensilla of tarsi, maxillary palps and antennae. Other types of sensilla were not labelled, nor were the cuticle and dendrites of the sensory cells. No binding of radioactively labelled glucose or bicarbonate was detected, in disagreement with the hypothesis that this class of proteins is involved in the CO 2 -sensing cascade. Our experimental data suggest that the proteins described here could be involved in contact chemoreception in Orthoptera.Keywords: chemosensory proteins; contact sensilla; disulfide bridges; Schistocerca gregaria; sequence analysis.Locusts and grasshoppers are major pests in agriculture. They have a solitary and a gregarious phase, characterized by different behaviour and morphological features [1]. All crop damage is caused by individuals in the gregarious phase.In the species Schistocerca gregaria, the shift from the solitary to the gregarious phase is preceded by an associating phase, triggered by volatile aromatic compounds, such as guaiacol, veratrol and phenylacetonitrile [2]. In the gregarious phase, the same chemicals, and perhaps related structures, induce aggregation of great numbers of individuals. Under these conditions this species becomes a plague and can destroy entire crops. Therefore, it is evident that these insects rely on chemical communication and that their populations could be controlled by the use of the appropriate chemical stimuli.Despite such pressing objectives, biochemical study of the olfactory system had been limited until recently to Lepidopteran species with large antennae. In the last few years, however, molecular biology techniques have made such research feasible in small insects of wider interest, such as Drosophila melanogaster. In this paper we report the isolation of soluble low-molecularmass proteins in antennae, tarsi and labrum of S. gregaria, their complete structural characterization by combined Edman degradation/MS procedures and the cloning of...

The relative importance that biomechanical and biochemical leaf traits have on photosynthetic capacity would depend on a complex interaction of internal architecture and physiological differences. Changes in photosynthetic capacity on a leaf area basis and anatomical properties during leaf development were studied in a deciduous tree, Prunus persica, and an evergreen shrub, Olea europaea. Photosynthetic capacity increased as leaves approached full expansion. Internal CO 2 transfer conductance (g i ) correlated with photosynthetic capacity, although, differences between species were only partially explained through structural and anatomical traits of leaves. Expanding leaves preserved a close functional balance in the allocation of resources of photosynthetic component processes. Stomata developed more rapidly in olive than in peach. Mesophyll thickness doubled from initial through final stages of development when it was twice as thick in olive as in peach. The surface area of mesophyll cells exposed to intercellular air spaces per unit leaf area tended to decrease with increasing leaf expansion, whereas, the fraction of mesophyll volume occupied by the intercellular air spaces increased strongly. In the sclerophyllous olive, structural protection of mesophyll cells had priority over efficiency of photochemical mechanisms with respect to the broad-leaved peach. The photosynthetic capacity of these woody plants during leaf development relied greatly on mesophyll properties, more than on leaf mass per area ratio (LMA) or nitrogen (N) allocation. Age-dependent changes in diffusion conductance and photosynthetic capacity affected photosynthetic relationships of peach versus olive foliage, evergreen leaves maturing functionally and structurally a bit earlier than deciduous leaves in the course of adaptation for xeromorphy.

The quality of virgin olive oil (VOO) is strictly related to the concentrations of phenolic and volatile compounds, which are strongly affected by the operative conditions of the VOO mechanical extraction process. The aim of this work is to study the impact of a new technology such as flash thermal conditioning (FTC) on olive paste structural modification and on VOO quality. The evaluation of olive paste structure modification by cryo-scanning electron microscopy (cryo-SEM) showed that the application of FTC after crushing produces significant differences in terms of the breaking of the parenchyma cells and aggregation of oil droplets in comparison to the crushed pastes. The virgin olive oil flash thermal conditioning (VOO-FTC) featured a higher concentration of volatile compounds compared to that in the control, particularly of all saturated and unsaturated aldehydes and esters, whereas the phenolic concentration was higher in VOO obtained from the traditional process (VOO-C).

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Fibrin is a suitable matrix for EPC growth, differentiation and angiogenesis capability, suggesting that fibrin gel may be very useful for regenerative medicine.