Warm‐night temperature alters paternal allocation strategy in a North temperate‐zone butterfly

Warming temperatures are greatly impacting wild organisms across the globe. Some of the negative impacts of climate change can be mitigated behaviorally, for example, by changes in habitat and oviposition site choice. Temperatures are reportedly warming faster at night than during the day, yet studies assessing the impacts of increasing night temperature are rare. We used the Finnish Glanville fritillary butterfly (Melitaea cinxia) as study species and exposed adult butterflies of both sexes to warmer night conditions. Under a seminatural outdoor enclosure, we assessed whether females base their oviposition choices primarily on habitat site characteristics (open, suggestive of dry meadows, versus covered by a coarse canopy, suggestive of pastures) or on plant condition (dry vs. lush), and if their choice is altered by the thermal conditions experienced at night. As exposure to warmer environmental conditions is expected to increase resting metabolic rate and potentially reduce life expectancy, we further assessed the fitness implications of warm‐night temperatures. We found that females prefer open sites for oviposition and that females do not switch their oviposition strategy based on the thermal conditions they experienced at night prior to the reproductive event. Exposure to warm nights did not influence female lifespan, but the egg hatching success of their offspring was reduced. In addition, we found that males exposed to warm nights sired larger clutches with higher hatching rate. As warm‐night exposure reduced male lifespan, this may imply a switch in male resource allocation strategy toward increased offspring quality. The present work adds on to the complex implications of climate warming and highlights the importance of the often‐neglected role of males in shaping offspring performance.     

Elicitin genes in <Emphasis Type="Italic">Phytophthora infestans</Emphasis> are clustered and interspersed with various transposon-like elements

Sequencing and annotation of a contiguous stretch of genomic DNA (112.3 kb) from the oomycete plant pathogen Phytophthora infestans revealed the order, spacing and genomic context of four members of the elicitin (inf) gene family. Analysis of the GC content at the third codon position (GC3) of six genes encoded in the region, and a set of randomly selected coding regions as well as random genomic regions, showed that a high GC3 value is a general feature of Phytophthora genes that can be exploited to optimize gene prediction programs for Phytophthora species. At least one-third of the annotated 112.3-kb P. infestans sequence consisted of transposons or transposon-like elements. The most prominent were four Tc3/gypsy and Tc1/copia type retrotransposons and three DNA transposons that belong to the Tc1/mariner, Pogo and PiggyBac groups, respectively. Comparative analysis of other available genomic sequences suggests that transposable elements are highly heterogeneous and ubiquitous in the P. infestans genome.Electronic Supplementary Material Supplementary material is available for this article at     

Genetic transformation of Alstroemeria using particle bombardment

Transgenic plants were obtained after particle bombardment of embryogenic callus derived from stem segments of two tetraploid Alstroemeria genotypes with plasmids containing different selection/reporter genes. Firstly, a plasmid containing a firefly luciferase reporter gene driven by the maize ubiquitin promoter (Ubi1), was bombarded into both friable embryogenic callus and proembryos. Transient and stable expression of luciferase was visually detected by a luminometer. This selection method is non-destructive and can be applied over the whole developmental process from callus to embryo and plantlet. Molecular proof of transformation was obtained both by PCR analysis and Southern hybridization. Secondly, a plasmid containing the bar gene together with an uidA gene coding for -glucuronidase both driven by the Ubi1 promoter was bombarded into proembryos. The transgenic callus was effectively selected from the callus clumps four months after bombardment on a medium containing 5 mg/l phosphinotricin (PPT). Selection by PPT was efficient and labour-saving. Stable expression of GUS was confirmed by the histochemical staining assay and molecular proof was obtained by PCR analysis.     

A candidate locus for variation in dispersal rate in a butterfly metapopulation

Frequent extinctions of local populations in metapopulations create opportunities for migrant females to establish new populations. In a metapopulation of the Glanville fritillary butterfly (Melitaea cinxia), more mobile individuals are more likely to establish new populations, especially in habitat patches that are poorly connected to existing populations. Here we show that flight metabolic rate and the frequency of a specific allele of the metabolic enzyme phosphoglucose isomerase (pgi) were both highest in newly established, isolated populations. Furthermore, genotypes with this pgi allele had elevated flight metabolic rates. These results suggest that genetic variation in pgi or a closely linked locus has a direct effect on flight metabolism, dispersal rate, and thereby on metapopulation dynamics in this species. These results also contribute to an emerging understanding of the mechanisms by which population turnover in heterogeneous landscapes may maintain genetic and phenotypic variation across populations.     

Multivitamin production in Lactococcus lactis using metabolic engineering

The dairy starter bacterium Lactococcus lactis has the potential to synthesize both folate (vitamin B11) and riboflavin (vitamin B2). By directed mutagenesis followed by selection and metabolic engineering we have modified two complicated biosynthetic pathways in L. lactis resulting in simultaneous overproduction of both folate and riboflavin: Following exposure to the riboflavin analogue roseoflavin we have isolated a spontaneous mutant of L. lactis strain NZ9000 that was changed from a riboflavin consumer into a riboflavin producer. This mutant contained a single base change in the regulatory region upstream of the riboflavin biosynthetic genes. By the constitutive overproduction of GTP cyclohydrolase I in this riboflavin-producing strain, the production of folate was increased as well. Novel foods, enriched through fermentation using these multivitamin-producing starters, could compensate the B-vitamin-deficiencies that are common even in highly developed countries and could specifically be used in dietary foods for the large fraction of the Caucasian people (10-15%) with mutations in the methylene tetrahydrofolate reductase (MTHFR).     

Structure of the human amyloid-precursor-like protein gene APLP1 at 19q13.1

Amyloid-precursor-like protein 1 (APLP1) is a membrane-associated glycoprotein, whose gene is homologous to the APP gene, which has been shown to be involved in the pathogenesis of Alzheimer’s disease. APLP1 is predominantly expressed in brain, particularly in the cerebral cortex postsynaptic density. The genomic organization of mouse APLP1 has been determined, and the human gene has been mapped to chromosomal region 19q13.1. In the present study, the entire sequence of human APLP1 has been determined from a cosmid clone, and the genomic structure has been determined. The gene is 11.8 kb long and contains 17 exons. We have previously mapped the gene for congenital nephrotic syndrome (CNF) to the APLP1 region, to the vicinity of marker D19S610 located between markers D19S191 and DS19608. APLP1 is the only known gene in the vicinity of the marker D19S610. Because of its location and the proposed interference of amyloid with basement membrane assembly, APLP1 has been considered a candidate gene for CNF. All exon regions of the gene were amplified by the polymerase chain reaction and sequenced from DNA of CNF patients. No differences were observed between CNF patients and controls, suggesting that mutations in APLP1 are not involved in the etiology of CNF. Received: 11 June 1997 / Accepted: 27 October 1997     

Dispersal and species’ responses to climate change

Dispersal is fundamental in determining biodiversity responses to rapid climate change, but recently acquired ecological and evolutionary knowledge is seldom accounted for in either predictive methods or conservation planning. We emphasise the accumulating evidence for direct and indirect impacts of climate change on dispersal. Additionally, evolutionary theory predicts increases in dispersal at expanding range margins, and this has been observed in a number of species. This multitude of ecological and evolutionary processes is likely to lead to complex responses of dispersal to climate change. As a result, improvement of models of species’ range changes will require greater realism in the representation of dispersal. Placing dispersal at the heart of our thinking will facilitate development of conservation strategies that are resilient to climate change, including landscape management and assisted colonisation. Synthesis This article seeks synthesis across the fields of dispersal ecology and evolution, species distribution modelling and conservation biology. Increasing effort focuses on understanding how dispersal influences species' responses to climate change. Importantly, though perhaps not broadly widely‐recognised, species' dispersal characteristics are themselves likely to alter during rapid climate change. We compile evidence for direct and indirect influences that climate change may have on dispersal, some ecological and others evolutionary. We emphasise the need for predictive modelling to account for this dispersal realism and highlight the need for conservation to make better use of our existing knowledge related to dispersal.     

Identification of two imidazole binding sites and key residues for substrate specificity in human primary amine oxidase AOC3

Human membrane primary amine oxidase (hAOC3; also known as vascular adhesion protein-1, VAP-1) is expressed upon inflammation in most tissues, where its enzymatic activity plays a crucial role in leukocyte trafficking. We have determined two new structures of a soluble, proteolytically cleaved form of hAOC3 (sAOC3), which was extracted from human plasma. In the 2.6 ? sAOC3 structure, an imidazole molecule is hydrogen bonded to the topaquinone (TPQ) cofactor, which is in an inactive on-copper conformation, while in the 2.95 ? structure, an imidazole molecule is covalently bound to the active off-copper conformation of TPQ. A second imidazole bound by Tyr394 and Thr212 was identified in the substrate channel. We furthermore demonstrated that imidazole has an inhibitory role at high concentrations used in crystallization. A triple mutant (Met211Val/Tyr394Asn/Leu469Gly) of hAOC3 was previously reported to change substrate preferences toward those of hAOC2, another human copper-containing monoamine oxidase. We now mutated these three residues and Thr212 individually to study their distinct role in the substrate specificity of hAOC3. Using enzyme activity assays, the effect of the four single mutations was tested with four different substrates (methylamine, benzylamine, 2-phenylethylamine, and p-tyramine), and their binding modes were predicted by docking studies. As a result, Met211 and Leu469 were shown to be key residues for substrate specificity. The native structures of sAOC3 and the mutational data presented in this study will aid the design of hAOC3 specific inhibitors.     

Quantitative genetic analysis of responses to larval food limitation in a polyphenic butterfly indicates environment‐ and trait‐specific effects

Different components of heritability, including genetic variance (V_G), are influenced by environmental conditions. Here, we assessed phenotypic responses of life‐history traits to two different developmental conditions, temperature and food limitation. The former represents an environment that defines seasonal polyphenism in our study organism, the tropical butterfly Bicyclus anynana, whereas the latter represents a more unpredictable environment. We quantified heritabilities using restricted maximum likelihood (REML) procedures within an “Information Theoretical” framework in a full‐sib design. Whereas development time, pupal mass, and resting metabolic rate showed no genotype‐by‐environment interaction for genetic variation, for thorax ratio and fat percentage the heritability increased under the cool temperature, dry season environment. Additionally, for fat percentage heritability estimates increased under food limitation. Hence, the traits most intimately related to polyphenism in B. anynana show the most environmental‐specific heritabilities as well as some indication of cross‐environmental genetic correlations. This may reflect a footprint of natural selection and our future research is aimed to uncover the genes and processes involved in this through studying season and condition‐dependent gene expression.