Catastrophic events offer unique opportunities to study rapid population response to stress in natural settings. In concert with genetic variation, epigenetic mechanisms may allow populations to ...persist through severe environmental challenges. In 2010, the Deepwater Horizon oil spill devastated large portions of the coastline along the Gulf of Mexico. However, the foundational salt marsh grass, Spartina alterniflora, showed high resilience to this strong environmental disturbance. Following the spill, we simultaneously examined the genetic and epigenetic structure of recovering populations of S. alterniflora to oil exposure. We quantified genetic and DNA methylation variation using amplified fragment length polymorphism and methylation sensitive fragment length polymorphism (MS‐AFLP) to test the hypothesis that response to oil exposure in S. alterniflora resulted in genetically and epigenetically based population differentiation. We found high genetic and epigenetic variation within and among sites and found significant genetic differentiation between contaminated and uncontaminated sites, which may reflect nonrandom mortality in response to oil exposure. Additionally, despite a lack of genomewide patterns in DNA methylation between contaminated and uncontaminated sites, we found five MS‐AFLP loci (12% of polymorphic MS‐AFLP loci) that were correlated with oil exposure. Overall, our findings support genetically based differentiation correlated with exposure to the oil spill in this system, but also suggest a potential role for epigenetic mechanisms in population differentiation.
The information characteristics of AFLP and ISSR techniques were compared in the analysis of length polymorphism of gamma-treated mutant lines of Amaranthus cruentus and Amaranthus hypochondriacus x ...Amaranthus hybridus. Both of the techniques are widely used in the manner of universal marker system suitable for the analysis of any plant species, but differ in the time needed for the analyse and costs. Binary data matrices were used for statistical analyses. Cluster analysis was performed in UPGMA method using Euclidean distance to construct dendrograms and principal component analyses was used for generated data, too. Comparison of techniques was made on the graphs obtained from result of PCA and dendrograms that were obtained from results of cluster analysis. Matrix comparisons of Mantel test, for the correspondence of the similarity matrices was performed for the null hypothesis that there is no association between similarity matrices. In the analyzed set used in this study, ISSR primers produced 59% polymorphic bands, while AFLP primers produced 48% polymorphic bands and both of techniques were similar in their obtained information characteristics.
While traits and trait plasticity are partly genetically based, investigating epigenetic mechanisms may provide more nuanced understanding of the mechanisms underlying response to environment. Using ...AFLP and methylation‐sensitive AFLP, we tested the hypothesis that differentiation to habitats along natural salt marsh environmental gradients occurs at epigenetic, but not genetic loci in two salt marsh perennials. We detected significant genetic and epigenetic structure among populations and among subpopulations, but we found multilocus patterns of differentiation to habitat type only in epigenetic variation for both species. In addition, more epigenetic than genetic loci were correlated with habitat in both species. When we analysed genetic and epigenetic variation simultaneously with partial Mantel, we found no correlation between genetic variation and habitat and a significant correlation between epigenetic variation and habitat in Spartina alterniflora. In Borrichia frutescens, we found significant correlations between epigenetic and/or genetic variation and habitat in four of five populations when populations were analysed individually, but there was no significant correlation between genetic or epigenetic variation and habitat when analysed jointly across the five populations. These analyses suggest that epigenetic mechanisms are involved in the response to salt marsh habitats, but also that the relationships among genetic and epigenetic variation and habitat vary by species. Site‐specific conditions may also cloud our ability to detect response in replicate populations with similar environmental gradients. Future studies analysing sequence data and the correlation between genetic variation and DNA methylation will be powerful to identify the contributions of genetic and epigenetic response to environmental gradients.
Summary
Epigenetic mosaicism is a possible source of within‐plant phenotypic heterogeneity, yet its frequency and developmental origin remain unexplored. This study examines whether extant epigenetic ...heterogeneity within Lavandula latifolia (Lamiaceae) shrubs reflects recent epigenetic modifications experienced independently by different plant parts or, alternatively, it is the cumulative outcome of a steady lifetime process.
Leaf samples from different architectural modules (branch tips) were collected from three L. latifolia plants and characterized epigenetically by global DNA cytosine methylation and methylation state of methylation‐sensitive amplified fragment‐length polymorphism (MS‐AFLP) markers. Epigenetic characteristics of modules were then assembled with information on the branching history of plants. Methods borrowed from phylogenetic research were used to assess genealogical signal of extant epigenetic variation and reconstruct within‐plant genealogical trajectory of epigenetic traits.
Plants were epigenetically heterogeneous, as shown by differences among modules in global DNA methylation and variation in the methylation states of 6 to 8% of MS‐AFLP markers. All epigenetic features exhibited significant genealogical signal within plants. Events of epigenetic divergence occurred throughout the lifespan of individuals and were subsequently propagated by branch divisions.
Internal epigenetic diversification of L. latifolia individuals took place steadily during their development, a process which eventually led to persistent epigenetic mosaicism.
See also the Commentary on this article by Wetzel, 231: 1667–1669.
Acute fatty liver of pregnancy (AFLP) merupakan kegawatan obstetrik yang fatal akibat kegagalan hati yang ditandai dengan akumulasi lemak mikrovaskuler dalam hepatosit. Diagonis ditegakkan ...berdasarkan kriteria Swansea. Gejala umum yang terjadi pada AFLP berupa disfungsi hati yang berat dan cepat, disseminnated intravascular coagulopathy, hipoglikemia dan ensefalopati. Wanita 24 tahun, G1P0A0 31 minggu dengan AFLP dan hipoglikemia. Gejala muntah muntah empat hari, penurunan kesadaran tiga hari. Klinis apatis, sklera ikterik, dan anemia. Hasil laboratorium menunjukkan fungsi hati abnormal dan kadar glukosa darah rendah. Pemeriksaan ultrasonografi dan kardiotokografi menunjukkan stres janin. Pasien ASA III menjalani operasi seksio mendesak di bawah anestesi umum. Penatalaksanaan AFLP bersifat suportif. Pemilihan teknik anestesi perlu dipertimbangkan ada tidaknya koagulopati serta komplikasi lainya. Pada pasien ini dipilih menggunakan general anesthesia karena terdapat koagulopati dan penurunan kesadaran. Pascaoperasi pasien dirawat di ICU dilakukan terapi suportif berupa norepinefrin, dextrose, fresh frozen plasma/FFP, Continous Renal Replacement Therapy/CRRT, lactulosa, vitamin K, albumin untuk komplikasi yang terjadi. Pasien meninggal di hari perawatan ke-7. Kegagalan hati pada AFLP dan pengobatan yang didapat pasien dapat menyebabkan terjadinya komplikasi metabolik. Pada pasien ditemukan asidosis metabolik, peningkatan laktat dan hipoglikemia refracter. Terapi pengganti ginjal (renal replacement therapy /RRT) mungkin diperlukan, pada pasien ini telah dikerjakan CRRT, namun hasil yang didapat tidak begitu memuaskan.
rooting and acclimatization of two cultivars ‘Wojtek’ and ‘Zojka’ of blue honeysuckle (
var.
Sevast.) were studied. To the
conditions were transferred rooted and unrooted shoots. The post-effect of ...auxin type and concentration as well as microcutting and soil substrate types were tested. The genetic stability of the plantlets in relation to the mother plants by using amplified fragment length polymorphism (AFLP) and inter simple sequence repeat (ISSR) markers has been also determined. It has been found that
rooted cuttings of both cultivars showed a higher survival rate (max. 88%) and better growth and development when they were rooted on a medium containing a low auxin level (1.0 mg·dm
). The results of the second experiment showed successful
rooting of blue honeysuckle shoots without auxin treatment. Higher
rooting and survival rate in the greenhouse have been observed for ‘Wojtek’ (max. 96%) than ‘Zojka’ (max. 88%). Better growth and development of shoots and roots were observed on peat alone or a mixture of peat and perlite as compared to a mixture of peat and sand. The micropropagated plantlets appeared similar to mother plants. Molecular analysis confirmed a high level of genetic stability of blue honeysuckle after 2 years of
propagation. However, among the cultivars studied, ‘Wojtek’ showed slightly higher genetic stability than ‘Zojka’ (99.5% and 97.7%, respectively). For ‘Zojka’ plants, the degree of variation was comparable for AFLP and ISSR markers. For ‘Wojtek’, no polymorphism was detected using the ISSR analysis in contrast to the AFLP analysis.
As plantas daninhas são causa do encarecimento das lavouras, entre elas está Conyza spp, conhecida como buva. Marcadores moleculares vem sendo utilizados para complementar sua caracterização. A ...técnica AFLP (Amplified Fragment Length Polymorphism) é adaptada para diversas análises genéticas, fornecendo alta cobertura do genoma. Com objetivo de caracterizar molecularmente morfotipos de buva, foram coletadas 60 plantas da UENP – Bandeirantes/PR. A análise molecular com AFLP seguiu etapas de digestão, ligação de adaptadores, amplificação pré-seletiva e seletiva, utilizando combinação de seis pares de primers AFLP. Os fragmentos foram separados em gel de poliacrilamida 8% e corados com AgNo3. Dos 218 loci, 97 foram polimórficos sendo 53 específicos para um morfotipo e 44 para o outro. A matriz de distância genética, a porcentagem de locos polimórficos, diversidade gênica de Nei (1978), e a distância genética foram obtidas utilizando o programa TFPGA (Tools For Population Genetcs Analyses). Os resultados da AMOVA mostram que a variação entre as populações é de 85,18% e dentro das populações é de 14,82% indicando que os morfotipos sejam espécies diferentes. Através das análises moleculares e principais características morfológicas demonstrou se que os morfotipos são espécies distintas, o morfotipo A é Conyza sumatrensis e o morfotipo B Conyza bonariensis.
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