Historical biogeography and mitogenomics of two endemic Mediterranean gorgonians (Holaxonia,Plexauridae)

Among the Mediterranean plexaurids, four species are endemic and despite their ecological importance, comprehensive studies on the evolution and biogeography of these organisms are lacking. Here, we explore the mitogenomic variability of two endemic, ecologically important Mediterranean Paramuricea species. We assess their phylogenetic relationships and provide first insights into their evolution and biogeography. Complete mitogenome sequences of Paramuricea clavata and Paramuricea macrospina were obtained using long-range PCR, primer-walking and Sanger sequencing. For an enlarged sample of Paramuricea species, maximum likelihood and Bayesian phylogenetic trees of the mitochondrial gene mtMutS were obtained and used to study the biogeographic history of Paramuricea through a statistical Dispersal-Vicariance (S-DIVA) method and a Dispersal Extinction Cladogenesis (DEC) model. Divergence time was estimated under strict and relaxed molecular clock models in BEAST using published octocoral mutation rates. Our results revealed high nucleotide diversity (2.6%) among the two Mediterranean endemics; the highest mutation rates were found in the mtMutS, Nad4 and Nad5. In addition, we found length polymorphisms in several intergenic regions and differences in mitochondrial genome size. The red gorgonian P. clavata was closely related to the Eastern Atlantic Paramuricea grayi rather than its Mediterranean congener, P. macrospina. Our biogeographic results provide evidence for the independent speciation of the Mediterranean species and point to a Miocene origin of the two endemics, highlighting the role played by the Messinian Salinity Crisis in the evolutionary history of Mediterranean organisms.     

Eating Behaviors and Indexes of Body Composition in Men and Women from the Québec Family Study

Objective: To put into relationship the dietary and anthropometric profile of men and women with their eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) and to assess whether gender and obesity status influence these associations. Research Methods and Procedures: Anthropometric measurements (including visceral adipose tissue accumulation), dietary profile (3‐day food record), and eating behaviors (Three‐Factor Eating Questionnaire) were determined in a sample of 244 men and 352 women. Results: Women had significantly higher cognitive dietary restraint and disinhibition scores than men (p < 0.0001). In both genders, scores for disinhibition and susceptibility to hunger, but not for cognitive dietary restraint, were higher in obese subjects than in overweight and nonobese subjects (p < 0.05). Positive correlations were observed between rigid restraint and most of the anthropometric variables studied (0.12 ≤ r ≤ 0.16). Moreover, in women, flexible restraint was negatively associated with body fat and waist circumference (r = ?0.11). Cognitive dietary restraint and rigid restraint were positively related to BMI among nonobese women (0.19 ≤ r ≤ 0.20), whereas in obese men, cognitive dietary restraint and flexible restraint tended to be negatively correlated with BMI (?0.20 ≤ r ≤ ?0.22; p = 0.10). Discussion: Gender could mediate associations observed between eating behaviors and anthropometric profile. It was also found that disinhibition and susceptibility to hunger are positively associated with the level of obesity. On the other hand, cognitive dietary restraint is not consistently related to body weight and adiposity, whereas rigid and flexible restraint are oppositely associated to obesity status, which suggests that it is important to differentiate the subscales of cognitive dietary restraint. Finally, counseling aimed at coping with disinhibition and susceptibility to hunger could be of benefit for the long‐term treatment of obesity.     

Structural properties of the protein SV-IV.

We have investigated the molecular mechanisms that produce different structural and functional behavior in the monomeric and trimeric forms of seminal vesicle protein no. 4, a protein with immunomodulatory, anti-inflammatory, and procoagulant activity secreted from the rat seminal vesicle epithelium. The monomeric and trimeric forms were characterized in solution by CD. Details of the self-association process and structural changes that accompany aggregation were investigated by different experimental approaches: trypsin proteolysis, sequence analysis, chemical modification, and computer modeling. The self-association process induces conformational change mainly in the 1-70 region, which appears to be without secondary structure in the monomer but contains alpha-helix in the trimer. In vivo, proteolysis of seminal vesicle protein no. 4 generates active peptides and this is affected by the monomer/trimer state, which is regulated by the concentration of the protein. The information obtained shows how conformational changes between the monomeric and trimeric forms represent a crucial aspect of activity modulation.     

Dramatic modulation of electron transfer in protein complexes by crosslinking.

The transfer of electrons between proteins is an essential step in biological energy production. Two protein redox partners are often artificially crosslinked to investigate the poorly understood mechanism by which they interact. To better understand the effect of crosslinking on electron transfer rates, we have constructed dimers of azurin by crosslinking the monomers. The measured electron exchange rates, combined with crystal structures of the dimers, demonstrate that the length of the linker can have a dramatic effect on the structure of the dimer and the electron transfer rate. The presence of ordered water molecules in the protein-protein interface may considerably influence the electronic coupling between redox centers.     

Production of phenyllactic acid by lactic acid bacteria: an approach to the selection of strains contributing to food quality and preservation

The ability of lactic acid bacteria (LAB) to produce phenyllactic (PLA) and 4-hydroxy-phenyllactic (OH-PLA) acids, metabolites involved in food quality and preservation, has been evaluated by HPLC analysis in 29 LAB strains belonging to 12 species widely used in the production of fermented foods. Metabolite production was demonstrated for all strains of the species Lactobacillus plantarum, Lactobacillus alimentarius, Lactobacillus rhamnosus, Lactobacillus sanfranciscensis, Lactobacillus hilgardii, Leuconostoc citreum, and for some strains of Lactobacillus brevis, Lactobacillus acidophilus and Leuconostoc mesenteroides subsp. mesenteroides. Strains were distinguished by analysis of variance in three groups including 15 strains that produced both metabolites (0.16-0.46 mM PLA and 0.07-0.29 mM OH-PLA), five strains accumulating in culture only PLA (0.17-0.57 mM) and nine non-producer strains (< or = 0.10 mM PLA and < or = 0.02 mM OH-PLA). Improvement of phenyllactic acid production was obtained in a selected L. plantarum strain by increasing the concentration of phenylalanine in culture and using low amounts of tyrosine.     

A herbivore that manipulates plant defence

Phytopathogens and herbivores induce plant defences. Whereas there is evidence that some pathogens suppress these defences by interfering with signalling pathways involved in the defence, such evidence is scarce for herbivores. We found that the invasive spider mite Tetranychus evansi suppresses the induction of the salicylic acid and jasmonic acid signalling routes involved in induced plant defences in tomato. This was reflected in the levels of inducible defence compounds, such as proteinase inhibitors, which in mite-infested plants were reduced to even lower levels than the constitutive levels in herbivore-free plants. Additionally, the spider mite suppressed the release of inducible volatiles, which are implicated in plant defence. Consequently, the mites performed much better on previously attacked plants than on non-attacked plants. These findings provide a new perspective on plant-herbivore interactions, plant protection and plant resistance to invasive species.     

An efficient method for producing alpha(1,3)-galactosyltransferase gene knockout pigs

We have reported relatively efficient methods for somatic cell nuclear transfer and for knocking out the alpha(1,3)-galactosyltransferase (alpha1,3-GT) gene in porcine fetal fibroblasts using a nonisogenic promoterless construct approach. Here we report the production of alpha1,3-GT gene knockout pigs using these procedures. Seven alpha1,3-GT gene knockout cell clones were identified by long-range PCR from 108 neomycin resistant (neo(R)) colonies, giving a 6.5% targeting efficiency. Three cell clones were used for nuclear transfer. Nuclear transfer was performed using a fusion before activation protocol using in vitro-matured adult oocytes. Between 51 and 110 fused couplets were transferred to 10 recipients synchronized 1 day behind the embryos. Parturition was induced on day 115, and piglets were delivered by caesarean section. Four recipients gave birth to a total of 18 live piglets. All pigs were female, and all three clones resulted in the birth of live pigs. alpha1,3-GT gene knockout pigs were identified by long-range PCR and confirmed by Southern blot analysis. The efficiency (embryos transferred/piglets born) of our cloning protocol was 1.9% for all transfers and 4.6% for animals that gave birth.