Derived esterase activity in Drosophila sechellia contributes to evolved octanoic acid resistance

2019 ◽  
Vol 28 (6) ◽  
pp. 798-806 ◽  
Author(s):  
S. M. Lanno ◽  
J. D. Coolon
2019 ◽  
Author(s):  
Chloe Heys ◽  
Adam M Fisher ◽  
Andrea D Dewhurst ◽  
Zenobia Lewis ◽  
Anne Lize

Adaptation to a novel food source can have significant evolutionary advantages. The fruit fly, Drosophila sechellia, is a specialist of the toxic plant noni (Morinda citrifolia). Little is known as to how D. sechellia has become resistant to the toxins in the fruit - comprised predominantly of octanoic acid - but to date, the behavioural preferences for the fruit and genetic architecture underlying them, have been well studied. Here, we examine whether the gut microbiota could have played a role in adaptation to the fruit. In the first series of experiments, we examine the gut microbiota of wild-type, laboratory reared flies and characterise the gut microbiota when reared on the natural host plant, versus a standard Drosophila diet. We show a rapid transition in the core bacterial diversity and abundance within this species and discover sole precedence of Lactobacillus plantarum when reared on M. citrifolia. We also discover that flies reared on a laboratory diet are more likely to carry bacterial pathogens such as Bacillus cereus, although their function in Drosophila is unknown. Flies reared on a laboratory diet have a significantly reduced weight but with no impact on the risk of death before adulthood, when compared to the wild noni diet. In the second series of experiments, we examine the potential role of the gut microbiota in adaptation to octanoic acid resistance in this species and its sister species, Drosophila melanogaster, to which the fruit is usually fatal. We use a combination of methods to analyse resistance to octanoic acid by conducting life history analysis, behavioural assays and bacterial analysis in both D. sechellia and D. melanogaster. We find that by creating experimental evolution lines of D. melanogaster supplemented with gut microbiota from D. sechellia, we can decrease D. melanogaster aversion to octanoic acid, with the flies even preferring to feed on food supplemented with the acid. We suggest this represents the first step in the evolutionary and ecological specialisation of D. sechellia to its toxic host plant, and that the gut microbiota, Lactobacillus plantarum in particular, may have played a key role in host specialisation.


2015 ◽  
Author(s):  
Yan Huang ◽  
Deniz Erezyilmaz

Many phytophagous insect species are ecologic specialists that have adapted to utilize a single host plant. Drosophila sechellia is a specialist that utilizes the ripe fruit of Morinda citrifolia, which is toxic to its sibling species, D. simulans. Here we apply multiplexed shotgun genotyping and QTL analysis to examine the genetic basis of resistance to M. citrifolia fruit toxin in interspecific hybrids. We find that at least four dominant and four recessive loci interact additively to confer resistance to the M. citrifolia fruit toxin. These QTL include a dominant locus of large effect on the third chromosome (QTL-IIIsima) that was not detected in previous analyses. The small-effect loci that we identify overlap with regions that were identified in selection experiments with D. simulans on octanoic acid and in QTL analyses of adult resistance to octanoic acid. Our high-resolution analysis sheds new light upon the complexity of M. citrifolia resistance, and suggests that partial resistance to lower levels of M. citrifolia toxin could be passed through introgression from D. sechellia to D. simulans in nature. The identification of a locus of major effect, QTL-IIIsima, is an important step towards identifying the molecular basis of host plant specialization by D. sechellia.


2017 ◽  
Vol 26 (4) ◽  
pp. 1148-1160 ◽  
Author(s):  
J. M. Andrade López ◽  
S. M. Lanno ◽  
J. M. Auerbach ◽  
E. C. Moskowitz ◽  
L. A. Sligar ◽  
...  

2001 ◽  
Vol 78 (3) ◽  
pp. 225-233 ◽  
Author(s):  
CORBIN D. JONES

The larvae of Drosophila sechellia are highly resistant to octanoic acid, a toxin found in D. sechellia's host plant, Morinda citrifolia. In contrast, close relatives of D. sechellia, D. simulans and D. melanogaster, are not resistant. In a series of interspecific backcrosses, 11 genetic markers were used to map factors affecting egg-to-adult (‘larval’) resistance in D. sechellia. The third chromosome harbours at least one partially dominant resistance factor. The second chromosome carries at least two mostly dominant resistance factors but no recessive factors. However, neither the X chromosome – which contains 20% of D. sechellia's genome – nor the fourth chromosome appear to affect resistance. These data suggest that larval resistance to Morinda toxin may involve only a handful of genes. These results, when compared with a previous analysis of adult resistance to Morinda toxin in D. sechellia, suggest that larval resistance may involve a subset of the genes underlying adult resistance.


2021 ◽  
Author(s):  
Joseph D. Coolon ◽  
Zachary Drum ◽  
Stephen Lanno ◽  
Sara Gregory ◽  
Serena Shimshak ◽  
...  

Drosophila sechellia is a dietary specialist endemic to the Seychelles islands that has evolved to consume the fruit of Morinda citrifolia. When ripe, the fruit of M. citrifolia contains octanoic acid and hexanoic acid, two medium chain fatty acid volatiles that deter and are toxic to generalist insects D. sechellia has evolved resistance to these volatiles allowing it to feed almost exclusively on this host plant. The genetic basis of octanoic acid resistance has been the focus of multiple recent studies, but the mechanisms that govern hexanoic acid resistance in <D. sechellia remain unknown. To understand how D. sechellia has evolved to specialize on M. citrifolia fruit and avoid the toxic effects of hexanoic acid, we exposed adult D. sechellia, D. melanogaster and D. simulans to hexanoic acid and performed RNA sequencing comparing their transcriptional responses to identify D. sechellia specific responses. Our analysis identified many more genes responding transcriptionally to hexanoic acid in the susceptible generalist species than in the specialist D. sechellia. Interrogation of the sets of differentially expressed genes showed that generalists regulated the expression of many genes involved in metabolism and detoxification whereas the specialist primarily downregulated genes involved in the innate immunity. Using these data we have identified interesting candidate genes that may be critically important in aspects of adaptation to their food source that contains high concentrations of HA. Understanding how gene expression evolves during dietary specialization is crucial for our understanding of how ecological communities are built and how evolution shapes trophic interactions.


1967 ◽  
Vol 17 (03/04) ◽  
pp. 321-334 ◽  
Author(s):  
J. P Soulier ◽  
Odette Prou-Wartelle ◽  
Liliane Hallé ◽  

SummaryThe preparation of thrombin-coagulase is described. The properties of thrombin-coagulase are compared with those of biothrombin: kinetics, thermostability, adsorption, chromatography, esterase activity, clotting activity, action on platelets and on factors V and VIII, susceptibility to inhibitors.Biothrombin and thrombin-coagulase are closely related but distinct. Both apparently derive from prothrombin. Prothrombin and coagulase combine to form a complex: thrombin-coagulase wherein both factors are necessary for its activity. Possible explanations for the difference between thrombin-coagulase and biothrombin are proposed.


1966 ◽  
Vol 16 (01/02) ◽  
pp. 018-031 ◽  
Author(s):  
S Sherry ◽  
Norma Alkjaersig ◽  
A. P Fletcher

SummaryComparative studies have been made of the esterase activity of plasmin and the streptokinase-activator of plasminogen on a variety of substituted arginine and lysine esters. Human plasmin preparations derived by different methods of activation (spontaneous in glycerol, trypsin, streptokinase (SK) and urokinase) are similar in their esterase activity; this suggests that the molecular structure required for such esterase activity is similar for all of these human plasmins. Bovine plasmin, on the other hand, differs from human plasmin in its activity on several of the substrates studied (e.g., the methyl esters of benzoyl arginine and tosyl, acetyl and carbobenzoxy lysine), a finding which supports the view that molecular differences exist between the two animal plasmins. The streptokinase-activator hydrolyzes both arginine and lysine esters but the ratios of hydrolytic activity are distinct from those of plasmin and of other activators of plasminogen. The use of benzoyl arginine methyl ester as a substrate for the measurement of the esterase activity of the streptokinase-activator is described.


Author(s):  
Magsumova O.A. ◽  
Postnikov M.A. ◽  
Ryskina E.A. ◽  
Tkach T.M. ◽  
Polkanova V.A.

One of the non-invasive methods for treating discoloration of hard tooth tissues is teeth whitening. The aim of this work is to assess the dynamics of changes in the acid resistance of enamel and hard tissues of teeth and the rate of its remineralization after the procedure of office teeth whitening. The study involved 123 patients aged 18 to 35 years with discoloration of various origins, with the color of hard tooth tissues on the Vita Classic A2 scale and darker. Before performing the office, teeth whitening procedure, all patients gave their written voluntary informed consent to participate in this study, as well as consent to the processing of personal data. Depending on the chosen method of office teeth whitening, patients were divided into 3 groups. The resistance of hard tooth tissues was judged based on the determination of TOER and CASRE tests. These indicators were determined at various times (5 days before the office teeth whitening procedure, 5 days after it, after 14, 30 days and 6 months). Regardless of the chosen whitening system, the office teeth whitening procedure is accompanied by a decrease in the enamel's resistance to acids and a decrease in the rate of its remineralization. The remineralizing function of oral fluid promotes the positive dynamics of the studied parameters after 14 days and after 30 days values increased due to the appointment of remineralizing therapy to all patients in 2 weeks after the teeth whitening procedure. After 6 months, all patients had high enamel resistance and the rate of its remineralization.


Alloy Digest ◽  
2019 ◽  
Vol 68 (10) ◽  

Abstract NSSMC Advanced 347AP is an austenitic stainless steel with excellent polythionic acid resistance and good high-temperature strength. This datasheet provides information on composition as well as creep. It also includes information on high temperature performance. Filing Code: SS-1310. Producer or source: Nippon Steel.


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