Hymenoptera is the most species-rich order in the Swedish fauna, and whilst over 80% of our known 9000 species are parasitoids, they are generally small and rarely seen and thus we still know very little about parasitoid hymenopterans and their ecology. By striving to properly classify them we can expand our knowledge on how they impact our ecological networks and use this information as a tool in conservation efforts. With this research we wanted to present new insights into the sparasionids in the Swedish fauna to aid in the design of future research concerning this group. The collection of sparasionids supplied by Station Linné had been divided into four groups, assumed to represent known species in the genus Sparasion, but so far no morphological or genetic studies have been conducted in this genus to substantiate these claims. We conducted morphological studies based on the few existing keys, and whilst they proved somewhat accurate, they were mostly inconclusive when compared to the groups presented within our molecular study. Sequencing of the CO1-gene for our specimens revealed the presence of cryptic species in this genus in addition to the previously assumed species. This shows that individuals in the genus Sparasion present here cannot be determined to species with the morphological information available today, and since cryptic species with similar morphological traits have now been discovered, more in-depth studies of their genetic make-up is the most logical step forward in future research.
In Chlamydomonas reinhardtii several nucleus-encoded proteins that participate in the mitochondrial oxidative phosphorylation are targeted to the organelle by unusually long mitochondrial targeting sequences. Here, we explored the components of the mitochondrial import machinery of the green alga. We mined the algal genome, searching for yeast and plant homologs, and reconstructed the mitochondrial import machinery. All the main translocation components were identified in Chlamydomonas as well as in Arabidopsis thaliana and in the recently sequenced moss Physcomitrella patens. Some of these components appear to be duplicated, as is the case of Tim22. In contrast, several yeast components that have relatively large hydrophilic regions exposed to the cytosol or to the intermembrane space seem to be absent in land plants and green algae. If present at all, these components of plants and algae may differ significantly from their yeast counterparts. We propose that long mitochondrial targeting sequences in some Chlamydomonas mitochondrial protein precursors are involved in preventing the aggregation of the hydrophobic proteins they carry.
This is the fifth in a series of Eurobarometer surveys on biotechnology and the life sciences. The surveys have been conducted in 1991, 1993, 1996, 1999 and in 2002. The survey is based on a representative sample of 16 500 respondents, approximately 1 000 in each EU member state (see report for exceptions). Survey design and analysis was conducted by an international research group ‘Life Sciences in European Society’ supported by DG Research. In a year when many European countries are involved in public discussions on aspects of biotechnology, this survey stands as a contribution to the informed debate.
Identification of genes controlling complex diseases has proven to be difficult; however, animal models may pave the way to determine how low penetrant genes interact to promote disease development. We have dissected the Cia5/Eae3 susceptibility locus on mouse chromosome 3 previously identified to control disease in experimental models of multiple sclerosis and rheumatoid arthritis. Congenic strains showed significant but small effects on severity of both diseases. To improve the penetrance, we have now used a new strategy that defines the genetic interactions. The QTL interacted with another locus on chromosome 15 and a partial advanced intercross breeding of the two congenic strains for eight generations accumulated enough statistical power to identify interactions with several loci on chromosome 15. Thereby, three separate loci within the original QTL could be identified; Cia5 affected the onset of arthritis by an additive interaction with Cia31 on chromosome 15, whereas the Cia21 and Cia22 affected severity during the chronic phase of the disease through an epistatic interaction with Cia32 on chromosome 15. The definition of genetic interactions was a prerequisite to dissect the Cia5 QTL and we suggest the partial advanced intercross strategy to be helpful also for dissecting other QTL controlling complex phenotypes.
Population studies have become important tools in conservation biology and genetic analyses are used to investigate genetic diversity within and among populations. Genetic variation can help improve fitness and ecological resilience. However, knowledge about genetic diversity is scarce for most wild species in Sweden. Insight in genetic population structure, can help us understand a species ́ ecological traits and improve species conservation. Fungi are fundamental components in terrestrial ecosystems, yet they have gotten little attention in conservatory work in Europe. In my bachelor thesis, by a short literature review and GIS- analysis of species occurrence data, I have developed a sampling scheme for a conservatory, genetic population study of the threatened pig’s ear mushroom, Gomphus clavatus. The population study aims to investigate genetic structures of the pig’s ear mushroom, in Sweden and surrounding countries. I collected occurrence data from nine countries and processed a total of 3232 findings, which were all compiled in Arcmap. A preliminary selection of localities in Sweden was made through identifying around twenty localities with recent findings, in protected areas. Eight localities of particular interest were included in the selection, one location with findings of morphologically divergent specimens were among those localities. For the surrounding countries, the preliminary selection included localities with findings reported between years 2015–2020. In my literature review, previous studies were not comparable in a way that could guide the design of a sampling scheme for the pig ́s ear mushroom. For clonal species, one should prioritize the total number of localities rather than the number of samples per site, and vice versa for sexually reproducing species. Since the pig ́s ear mushroom belongs in both groups, I suggest a combination of higher density sampling efforts at two localities, together with single sampling at a greater number of geographically distributed localities.
We present the first empirical treatment of the northernmost breeding dragonfly, Somatochlora sahlbergi. We sequenced populations from United States, Canada, Finland, Sweden and Norway for cytochrome oxidase I (COI) and D2 region of 28s. We found that, despite geographic barriers across its vast arctic range, S. sahlbergi is a single species. Not only does it appear to interbreed across its entire range, there also seems to be almost no variation among European and North American populations in their COI gene fragment (the barcode gene), which is usually extremely variable. We further found that characters thought to be diagnostic for the larvae of S. sahlbergi were absent in our European samples. We review and re-describe the habitat of this species based on new findings from recent field observations. Finally, we report for the first time the likely presence of this species in Japan. We hope our findings will encourage further study of this species and other under-studied insect taxa that inhabit the remote Arctic.
Impairment of nerve conduction is common in neurodegenerative and neuroinflammatory diseases such as multiple sclerosis (MS), and measurement of evoked potentials (visual, motor, or sensory) has been widely used for diagnosis and recently also as a prognostic marker for MS. We used a classical genetic approach to identify novel genes controlling nerve conduction. First, we used quantitative trait mapping in F2 progeny of B10/SJL mice to identify EAE31, a locus controlling latency of motor evoked potentials (MEPs) and clinical onset of experimental autoimmune encephalomyelitis. Then, by combining congenic mapping, in silico haplotype analyses, and comparative genomics we identified inositol polyphosphate-4-phosphatase, type II (Inpp4b) as the quantitative trait gene for EAE31. Sequence variants of Inpp4b (C/A, exon 13; A/C, exon 14) were identified as differing among multiple mouse strains and correlated with individual cortical MEP latency differences. To evaluate the functional relevance of the amino acid exchanges at positions S474R and H548P, we generated transgenic mice carrying the longer-latency allele (Inpp4b(474R/548P)) in the C57BL/6J background. Inpp4b(474R/548P) mice exhibited significantly longer cortical MEP latencies (4.5 ± 0.22 ms versus 3.7 ± 0.13 ms; P = 1.04 × 10(-9)), indicating that INPP4B regulates nerve conduction velocity. An association of an INPP4B polymorphism (rs13102150) with MS was observed in German and Spanish MS cohorts (3676 controls and 911 cases) (P = 8.8 × 10(-3)).
This study was carried out to identify a hitherto unknown species for Sweden within the Opiinae with the help of a thorough species description and gene sequencing of the Swedish material gathered in Station Linnés’ malaise trap project.
The study was carried out on 3 individuals, which were found in two malaise traps in Pajala and Övertorneå respectively and consisted of two females and one male. The results showed that the individuals of the study were the synonymized species Opius saevus/Apodesmia saeva, previously found in Iran, Scotland, South Korea, the Netherlands, Austria and Finland. That it is synonymized means, in this case, that there are two names for the species, as scientists do not quite agree on which genus it belongs to. The Swedish individuals are black with yellow legs, have an occipital carina that meets and merges into the hypoclypeal carina and a non-existent notauli. Other characters include an elliptical or wedge-shaped pterostigma, a distinct ovipositor tube, and 30 antennal segments.
Placing the species within Apodesmia or Opius cannot be done without further research. But by carrying out studies like this, the knowledge of the Swedish insect fauna is expanded among both researchers and the public. A complete revision is necessary within the Opiinae taxa to simplify future research and species determination, and thereafter reduce the number of synonymizations.