<Emphasis Type="Italic">MEFV</Emphasis> heterogeneity in Turkish Familial Mediterranean Fever patients

Turkey is one of the few countries in the world where Familial Mediterranean Fever (FMF), an autoinflammatory disease caused by mutations in MEFV, the gene encoding pyrin, is not rare. Many interesting studies regarding the genetics of Familial Mediterranean Fever in Turkey have been already published. Despite that different MEFV genetic profiles have been revealed for Turkish FMF patients, deriving from different regions of Turkey, a systematic population genetics analysis has not been carried out yet. The present study aims to investigate the population genetics of MEFV in Turkish FMF patients so as to additionally facilitate the clinical interpretation of individualized genetic data. All relevant studies have been recruited by searching PubMed with the terms “MEFV”, “FMF”, and “Turkey”. Seven of them, including 3,061 FMF patients, contained all necessary data concerning allelic and genotypic frequencies of the 4 commonest MEFV mutations in Turkey (M694V, V726A, M680I, E148Q). From all 6,122 MEFV alleles analyzed, the M694V mutation was recognized in 15.6–52.2% (mean 29.3%), the V726A in 1.5–9.7% (mean 4.8%), the M680I in 1.5–15.5% (mean 7.6%), and the E148Q in 3.2–13.9% (mean 5.5%). Unidentified mutations ranged from 0–42.9% (mean 16.8%). No mutations were found in 0–54.5% (mean 36.0%) of the patients. The allelic and genotypic frequencies of the most frequent mutation (M694V) showed aberration of the Hardy–Weinberg law for all 7 populations studied. By application of the Arlequin 2.0 population genetics software, the Fixation index (F _ST) was found to be 0.09994, thus demonstrating that the observed variability is mainly within (90.006%) and not among (9.994%) populations (P < 0.00001). Moreover, the global test of differentiation demonstrated that every population differs from each other (P < 0.00325). Finally, the Ewens–Watterson test of selective neutrality yielded to statistical significance in only 3 populations. In conclusion, Turkish FMF patients are characterized by an increased genetic heterogeneity, explained by the intrapopulation differentiation. Thus, the regional origin should be regarded as a determining factor in the diagnosis of FMF in Turkish patients.     

Polymorphism of a new Ty1-copia retrotransposon in durum wheat under salt and light stresses

Long terminal repeat retrotransposons are the most abundant mobile elements in the plant genome and play an important role in the genome reorganization induced by environmental challenges. Their success depends on the ability of their promoters to respond to different signaling pathways that regulate plant adaptation to biotic and abiotic stresses. We have isolated a new Ty1-copia-like retrotransposon, named Ttd1a from the Triticum durum L. genome. To get insight into stress activation pathways in Ttd1a, we investigated the effect of salt and light stresses by RT-PCR and S-SAP profiling. We screened for Ttd1a insertion polymorphisms in plants grown to stress and showed that one new insertion was located near the resistance gene. Our analysis showed that the activation and mobilization of Ttd1a was controlled by salt and light stresses, which strengthened the hypothesis that stress mobilization of this element might play a role in the defense response to environmental stresses.     

Kinetics of Aggregate Formation in Social Insects

A model for the kinetics of aggregation in social insects which accounts for stochastic effects arising from individual variability and covers both the early and the mature stages of the process is developed. Different aggregation scenarios are studied, depending on the degree of cooperativity and the mean population density. It is shown that under certain conditions, the system evolves slowly to a single cluster incorporating all individuals, or to two coexisting clusters of similar sizes. Present address: Department of Zoology, University of Oxford, OX1 3PS Oxford, UK.     

Wild type and <Emphasis Type="Italic">H43Y</Emphasis> variant of human <Emphasis Type="Italic">TRIM5α</Emphasis> show similar anti-human immunodeficiency virus type 1 activity both in vivo and in vitro

Polymorphisms in human genes have been shown to affect the rate of disease progression to acquired immune deficiency syndrome in human immunodeficiency virus type 1 (HIV-1)-infected individuals. Recently, tripartite motif 5α (TRIM5α) was identified as a factor that confers resistance to HIV-1 infection in Old World monkey cells. Subsequently, Sawyer et al. (Curr Biol 16:95–100, 2006) reported a single nucleotide polymorphism (H43Y) in the human TRIM5α gene and TRIM5α protein with 43Y was found to lose its ability to restrict HIV-1. In the present study, we reevaluated effects of this allele on in vitro anti-HIV-1 activity as well as on HIV-1 disease progression in European and Asian cohorts of HIV-1-infected individuals. Our epidemiological and molecular biological findings clearly indicate H43Y has a very minor effect on anti-HIV-1 activity of TRIM5α, suggesting that this allele is immaterial, at least in HIV-1-infected Europeans and Asians.     

Leaf anatomy and chloroplast ultrastructure of Mn-deficient orange plants

Leaf samples of Mn-deficient and Mn-sufficient (control) ‘Navelate’ orange plants grown in a greenhouse were taken to investigate the effects of Mn deficiency in leaf structure and chloroplast ultrastructure. Total leaf chlorophyll concentration was significantly lower in Mn-deficient plants than in control ones. Entire lamina thickness was not altered due to Mn deficiency. However, Mn deficiency resulted in disorganization of mesophyll cells, mainly of palisade parenchyma cells. The number of mesophyll chloroplasts per cellular area and their length were both affected negatively. The membranous system of chloroplasts was also disorganized. The percentages of starch grains and plastoglobuli per chloroplast of Mn-deficient leaves were significantly greater than those of control leaves.     

Identification of the major constituents of Hypericum perforatum by LC/SPE/NMR and/or LC/MS

The newly established hyphenated instrumentation of LC/DAD/SPE/NMR and LC/UV/(ESI)MS techniques have been applied for separation and structure verification of the major known constituents present in Greek Hypericum perforatum extracts. The chromatographic separation was performed on a C18 column. Acetonitrile-water was used as a mobile phase. For the on-line NMR detection, the analytes eluted from column were trapped one by one onto separate SPE cartridges, and hereafter transported into the NMR flow-cell. LC/DAD/SPE/NMR and LC/UV/MS allowed the characterization of constituents of Greek H. perforatum, mainly naphtodianthrones (hypericin, pseudohypericin, protohypericin, protopseudohypericin), phloroglucinols (hyperforin, adhyperforin), flavonoids (quercetin, quercitrin, isoquercitrin, hyperoside, astilbin, miquelianin, I3,II8-biapigenin) and phenolic acids (chlorogenic acid, 3-O-coumaroylquinic acid). Two phloroglucinols (hyperfirin and adhyperfirin) were detected for the first time, which have been previously reported to be precursors in the biosynthesis of hyperforin and adhyperforin.     

Interdomain association in fibronectin: insight into cryptic sites and fibrillogenesis

The process by which fibronectin (FN), a soluble multidomain protein found in tissue fluids, forms insoluble fibrillar networks in the extracellular matrix is poorly understood. Cryptic sites found in FN type III domains have been hypothesized to function as nucleation points, thereby initiating fibrillogenesis. Exposure of these sites could occur upon tension-mediated mechanical rearrangement of type III domains. Here, we present the solution structures of the second type III domain of human FN ((2)FNIII), and that of an interaction complex between the first two type III domains ((1-2)FNIII). The two domains are connected through a long linker, flexible in solution. A weak but specific interdomain interaction maintains (1-2)FNIII in a closed conformation that associates weakly with the FN N-terminal 30 kDa fragment (FN30 kDa). Disruption of the interdomain interaction by amino-acid substitutions dramatically enhances association with FN30 kDa. Truncation analysis of (1-2)FNIII reveals that the interdomain linker is necessary for robust (1-2)FNIII-FN30 kDa interaction. We speculate on the importance of this interaction for FN function and present a possible mechanism by which tension could initiate fibrillogenesis.     

Mechanisms of programmed cell death during oogenesis in <Emphasis Type="Italic">Drosophila virilis</Emphasis>

We describe the features of programmed cell death occurring in the egg chambers of Drosophila virilis during mid-oogenesis and late oogenesis. During mid-oogenesis, the spontaneously degenerating egg chambers exhibit typical characteristics of apoptotic cell death. As revealed by propidium iodide, rhodamine-conjugated phalloidin staining, and the TUNEL assay, respectively, the nurse cells contain condensed chromatin, altered actin cytoskeleton, and fragmented DNA. In vitro caspase activity assays and immunostaining procedures demonstrate that the atretic egg chambers possess high levels of caspase activity. Features of autophagic cell death are also observed during D. virilis mid-oogenesis, as shown by monodansylcadaverine staining, together with an ultrastructural examination by transmission electron microscopy. During the late stages of oogenesis in D. virilis, once again, the two mechanisms, viz., nurse cell cluster apoptosis and autophagy, operate together, manifesting features of cell death similar to those detailed above. Moreover, an altered form of cytochrome c seems to be released from the mitochondria in the nurse cells proximal to the oocyte. We propose that apoptosis and autophagy function synergistically during oogenesis in D. virilis in order to achieve a more efficient elimination of the degenerated nurse cells and abnormal egg chambers. The present study was co-financed within Op. Education by the European Social Fund and by National Resources via a grant (HRAKLEITOS 70/3/7164) to Professor L.H. Margaritis.