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- Global warming and chromosomal inversion adaptation in isolated islands: Drosophila subobscura populations from MadeiraPublication . Madrenas, Raquel; Balanyà, Joan; Arenas, Concepció; Khadem, Mahnaz; Mestres, FrancescGlobal warming is an environmental phenomenon to which species must adapt to survive. Drosophila sub obscura presents an adaptive capacity due to its chromosomal inversion polymorphism. Until now, the impact of global warming on this polymorphism has been studied in D. subobscura populations located either on a continental mainland or on islands not far from a continent. In this context, gene flow could be a relevant mechanism allowing the movement of thermally adapted inversions between populations. Our aim was to sample and study the chromosomal polymorphism on Madeira, a small isolated island in the Atlantic Ocean. We compared our findings with those reported in the same location approximately four and five decades ago. Moreover, we studied whether global warming has occurred on this island by analyz ing mean, maximum and minimum temperatures over a 55-year period. All atmospheric parameters have increased significantly, consistent with climate change expectations. Frequencies and chromosomal thermal index values of thermal adapted inversions remained quite stable over years. Furthermore, J, U and O chro mosomes are almost fixed for “warm” adapted inversions. Thus, if there is little genetic variability remaining and temperatures continue increasing, island populations of D. subobscura might be on the threshold of endangerment. However, apart from selection, genetic drift and inbreeding, other processes, such as phenotypic plasticity or thermoregulatory behavior, could be involved in the survival of the species’ populations. Finally, although in danger, D. subobscura is a generalist that lives in humanized environ ments, and this fact could favor its persistence on Madeira Island.
- Phytogeographical origin of Madeiran common beans based on phaseolin patternsPublication . Silva, Emanuel Marques da; Correia, Anísia Soraia Abreu; Lopes, Nuno Alexandre Amaral; Nóbrega, Humberto Gil Moreira; Ganança, José Filipe Teixeira; Domingues, Ana Maria; Khadem, Manhaz; Slaski, Jan Jacek; Carvalho, Miguel Ângelo Almeida Pinheiro deThe objective of this work was to determine the geographic origin of the Madeiran common bean (Phaseolus vulgaris) gene pool. Phaseolin patterns of 50 accessions representing the diversity of common bean collected in Madeira, Portugal, and conserved in the ISOPlexis Germplasm Bank, were analysed using the Experion automated electrophoresis system, based on lab-on-a-chip technology. Five common bean standard varieties with typical phaseolin patterns were used to determine the phytogeographical origin of the Madeiran common bean accessions. Ninety two percent of the accessions exhibited a phaseolin pattern consistent with the one of common bean types belonging to the Andean gene pool, while the origin of the remaining 8% of the accessions was indistinguishable. The application of a similarity coefficient of 85%, based on Pearson correlations, increases the number of accessions with uncertain pattern. The analytical approach used permitted the determination of the origin of the common bean gene pool, which is Andean in 98% of the cases, and clustering of the observed variability among the Madeiran common beans.
- Wolbachia (Alphaproteobacteria: Rickettsiales) infections in isolated aphid populations from oceanic islands of the azores archipelago: revisiting the supergroups M and NPublication . Moreira, Marta; Aguiar, António M. F.; Bourtzis, Kostas; Latorre, Amparo; Khadem, MahnazAphids (Hemiptera: Aphididae) have provided a suitable model to study endosymbionts, their community, and dynamics since the discovery of the obligate endosymbiont Buchnera aphidicola in these organisms. In previous studies, Wolbachia was found in some aphid species. In the present study, we report the prevalence of Wolbachia in aphids sampled from a geographically isolated region (Azores Islands), aiming at a better understanding and characterization of the two newly reported supergroups, M and N. The description of the supergroup M was based on 16S rRNA as well as some protein-coding genes. However, the assignment of the supergroup N was according to 16S rRNA gene sequences of a very few samples. We collected aphid samples and performed phylogenetic analysis of 16S rRNA gene as well as four protein-coding genes (gatB, ftsZ, coxA, and hcpA). The results demonstrate that the 16S rRNA gene data can unambiguously assign the strain supergroup and that the two supergroups, N and M, are equally prevalent in Azorean aphids. The available sequence data for the protein-coding markers can identify supergroup M but the status of supergroup N is inconclusive, requiring further studies. The data suggest that horizontal transmission of Wolbachia (Hertig and Wolbach) between two phylogenetically distant aphid species cohabiting the same plant host.
- Molecular identification and VOMs characterization of Saccharomyces cerevisiae strains isolated from Madeira region winery environmentsPublication . Castillo, Mariangie; Silva, Emanuel da; Câmara, José S.; Khadem, MahnazThe quality and typical characteristic of wines depends, among other factors, on the volatile organic metabolites (VOMs) that are biosynthesized by yeasts, mainly Saccharomyces cerevisiae species. The yeast strain influences the diversity and proportions of the VOMs produced during the fermentation process, as the genetic predisposition of the strains is a by-product of selective adaptation to the ecosystem. The present work reports the characterization of S. cerevisiae strains isolated from grape must, used in the Demarcated Region of Madeira (DRM) for winemaking. Yeast species were identified by amplification and by restriction fragment length polymorphism (RFLP) analysis of the region 5.8S-internal transcribed spacers (PCR-RFLP of 5.8S-ITS) of ribosomal DNA (rDNA). The strains identification was performed by analyzing the RFLP pattern of mitochondrial DNA (RFLP-mtDNA). The representative strains were selected for the characterization of the volatile profile through headspace solid-phase microextraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. A total of 77 VOMs were identified. Higher alcohols, esters, and fatty acids were the major chemical families representing 63%, 16%, and 9%, respectively, in strain A and 54%, 23%, and 15% in strain B. The results indicate the influence of the strain metabolism in the production of VOMs, many of which probably participate in the aroma of the corresponding wines.
- Multilocus analysis of nucleotide variation in Drosophila madeirensis, an endemic species of the Laurisilva forest in MadeiraPublication . Khadem, M.; Munté, A.; Camacho, R.; Aguadé, M.; Segarra, C.Drosophila madeirensis is an endemic species of Madeira that inhabits the island Laurisilva forest. Nucleotide variation in D. madeirensis is analysed in six genomic regions and compared to that previously reported for the same regions in Drosophila subobscura, an abundant species in the Palearctic region that is closely related to D. madeirensis. The gene regions analysed are distributed along the O3 inversion. The O3 arrangement is monomorphic in D. madeirensis, and it was present in ancestral populations of D. subobscura but went extinct in this species after the origin of the derived OST and O3+4 arrangements. Levels of nucleotide polymorphism in D. madeirensis are similar to those present in the OST and O3+4 arrangements of D. subobscura, and the frequency spectrum is skewed towards rare variants. Purifying selection against deleterious nonsynonymous mutations is less effective in D. madeir ensis. Although D. madeirensis and D. subobscura coexist at present in Madeira, no clear evidence of introgression was detected in the studied regions.
- Genetic variability of high molecular weight glutenin subunits in bread wheat from continental Portugal, Madeira and Canary IslandsPublication . Santos, Teresa M. M. dos; Nóbrega, Humberto; Ganança, José Filipe Teixeira; Silva, Emanuel; Afonso, Desire; Gutiérres, Abílio F. M.; Slaski, Jan J.; Khadem, Manhaz; Carvalho, Miguel Â. A. Pinheiro deThe genetic variability of high molecular weight glutenin subunits (HMWGS) composition at the Glu-1 loci in bread wheat (Triticum aestivum L.) was studied electrophoretically using the SDS–PAGE in 3,470 individuals representing 159 populations originated from the Canary Islands (Spain), the Archipelago of Madeira (Portugal) and the continental Portugal. A total of 25 alleles were detected, resulting in 69 different allele combinations. The geographical distribution of the high molecular weight glutenin alleles confirms historical data regarding circulation of wheat germplasm between the Iberian Peninsula and Madeira and between Madeira and the Canary Islands and vice versa.
- Larval cestodes infecting the deep-water fish, Cataetyx laticeps (Pisces: Bythitidae) from Madeira Archipelago, Atlantic OceanPublication . Costa, Graça; Khadem, Mahnaz; Dellinger, Thomas; Biscoito, Manuel; Moreira, Egberto MeloParasites of deep-water fishes are less known in comparison to the parasites of fishes living in the demersal and epipelagic ocean zones. In the present research note we report the occurrence of larval trypanorhynch cestodes in a rare deep-water fish, the deep-water brotula, Cataetyx laticeps. Based on the 28S rDNA (region D1-D3) sequence homology and the phylogenetic analysis, the larval cestodes are putatively assigned to the genus Grillotia. It is suggested that the definitive host of this trypanorhynch is a batoid.
- Endohelminth parasites of the blacktail comber Serranus atricauda (Pisces: Serranidae), from Madeira Archipelago (Atlantic Ocean)Publication . Costa, Graça; Khadem, Mahnaz; Silva, Sofia; Moreira, Egberto Melo; D’Amélio, StefanoFour different endohelminth parasite taxa were found in the viscera of the blacktail comber Serranus atricauda Günther, 1874 caught in the Madeira Archipelago. Nematodes were the dominant group, represented by 2 different taxa, Hysterothylacium spp. Ward & Magath, 1917 and Procamallanus (Spirocamallanus) halitrophus Fusco & Overstreet, 1978 comb. n. Plerocerci of the trypanorhynch Pseudogrillotia epinepheli (synonym: Grillotia epinepheli) Scholz, Garippa & Scala, 1993, and cystacanths of the acanthocephalan Bolbosoma vasculosum Rudolphi, 1819 were found in the visceral cavity. New host records for P. (S.) halitrophus and P. epinepheli and the extension of the geographic distribution of these 2 parasite species provide evidence of parasite transference between the Madeira Archipelago, the Mediterranean and the Gulf of Mexico. The paucity of the parasite fauna of blacktail comber reflect a combination of fish host selective feed ing on particular dietary items and its territorial behaviour.
- Helminth parasites of the Atlantic chub mackerel, Scomber colias Gmelin, 1789 from Canary Islands, Central North Atlantic, with comments on their relations with other Atlantic regionsPublication . Costa, Graça; Cavallero, Serena; D’Amélio, Stefano; Paggi, Lia; Santamaria, Maria; Perera, Clara; Santos, Maria; Khadem, MahnazEleven parasite taxa were found infecting 68 Atlantic chub mackerel, Scomber colias Gmelin, 1789 from the Canary Islands, Central North Atlantic. The most abundant parasites were the gill monogenean Pseudokuhnia minor (P = 54.4%), larval anisakid nematodes (P = 11.8%) in the body cavity, a larval tetraphyllidean infecting bile ducts (P = 8.8%) and didymozoid digeneans infecting the gills (P = 7.4%). No correlation between fish length and abundance of infection with these parasites was found. Within the Atlantic, the comparison of present results with previous reports on the occurrence of parasites in this fish host, might suggest that there is more than one population unit of Atlantic chub mackerel in the Eastern Atlantic
- Effects of nonthermal atmospheric-pressure plasma on Drosophila developmentPublication . Ferreira, Margarida I.; Gomes, José Gabriel Lira; Benilov, Mikhail S.; Khadem, MahnazNonthermal atmospheric-pressure plasma (NTAPP) is known to induce a wide range of responses at the cellular level. This study is concerned with the effects of NTAPP on a eukaryotic organism as a whole: Drosophila melanogaster. Exposure influenced the larval viability and caused an array of traits that can be classified into three major groups: (1) phenotypic anomalies in larvae (such as melanotic masses, melanized and broken trachea, incomplete shedding of the old cuticle during molting), morphological anomalies of pupae (small size, abnormal form, aberrant development, cryptocephalic forms), and developmental anomalies in adults (abnormal formation of wing, legs, and thorax); (2) larval behavior alteration (nonfeeding of first and second instar larvae, premature wandering, running away from food, immature pupae formation); and (3) excessive fat accumulation and lipid oxidation. The majority of the observed traits can be linked to molting and metamorphosis controlled by the endocrine system, in particular with the steroid hormone ecdysone. Results support the hypothesis that the interaction of NTAPP with the membranes of various organs can have a major role in the interruption of normal ecdysogenesis.