Analysis of diverse eukaryotes suggests the existence of an ancestral mitochondrial apparatus derived from the bacterial type II secretion system

The type 2 secretion system (T2SS) is present in some Gram-negative eubacteria and used to secrete proteins across the outer membrane. Here we report that certain representative heteroloboseans, jakobids, malawimonads and hemimastigotes unexpectedly possess homologues of core T2SS components. We show that at least some of them are present in mitochondria, and their behaviour in biochemical assays is consistent with the presence of a mitochondrial T2SS-derived system (miT2SS). We additionally identified 23 protein families co-occurring with miT2SS in eukaryotes. Seven of these proteins could be directly linked to the core miT2SS by functional data and/or sequence features, whereas others may represent different parts of a broader functional pathway, possibly also involving the peroxisome. Its distribution in eukaryotes and phylogenetic evidence together indicate that the miT2SS-centred pathway is an ancestral eukaryotic trait. Our findings thus have direct implications for the functional properties of the early mitochondrion

Amoniaková signalizace u kolonií Saccharomyces cerevisae: Exprese transportérů aminokyselin u kmenů defektních v SPS sensoru

The capability of yeast colonies to produce ammonia depends on correct function of SPS sensor composed of Ssy1p, Ssy5p and Ptr3p. The obtained data indicate that SPS sensor influences the expression of amino acid transporter genes in yeast colonies by different way when compared with its function in yeast liquid culture

Fish with red fluorescent eyes forage more efficiently under dim, blue-green light conditions

Abstract Background Natural red fluorescence is particularly conspicuous in the eyes of some small, benthic, predatory fishes. Fluorescence also increases in relative efficiency with increasing depth, which has generated speculation about its possible function as a “light organ” to detect cryptic organisms under bluish light. Here we investigate whether foraging success is improved under ambient conditions that make red fluorescence stand out more, using the triplefin Tripterygion delaisi as a model system. We repeatedly presented 10 copepods to individual fish (n = 40) kept under a narrow blue-green spectrum and compared their performance with that under a broad spectrum with the same overall brightness. The experiment was repeated for two levels of brightness, a shaded one representing 0.4% of the light present at the surface and a heavily shaded one with about 0.01% of the surface brightness. Results Fish were 7% more successful at catching copepods under the narrow, fluorescence-friendly spectrum than under the broad spectrum. However, this effect was significant under the heavily shaded light treatment only. Conclusions This outcome corroborates previous predictions that fluorescence may be an adaptation to blue-green, heavily shaded environments, which coincides with the opportunistic biology of this species that lives in the transition zone between exposed and heavily shaded microhabitats

Detailed proteome mapping of newly emerged honeybee worker hemolymph and comparison with the red-eye pupal stage

International audienceAbstractThe honeybee, Apis mellifera, undergoes complete metamorphosis before transitioning to the adult stage. The newly emerged individual and the red-eye pupa stage are well defined and easily recognizable in the time life cycle honeybee and, therefore, very useful for studying physiological and developmental factors. We analyzed in detail the hemolymph proteome of newly emerged honeybee worker using 2D-E-MS/MS (pI 3-10 and 4-7). The comparison of identical hemolymph volumes (20 μL per 2D-E) for newly emerged bee and red-eye pupa revealed a dramatic decrease in the number of spots (qualitative changes) and overall protein quantity during the non-feeding stage. The results increase our knowledge about honeybee metamorphosis during the non-feeding period and clarify previous findings regarding particular proteins. The results will be useful for future comparative physiological, developmental, and host-pathogen studies on individual or population level

Giardia intestinalis incorporates heme into cytosolic cytochrome b5.

International audience: The anaerobic intestinal pathogen Giardia intestinalis does not possess enzymes for heme synthesis and it also lacks the typical set of hemoproteins that are involved in mitochondrial respiration and cellular oxygen stress management. Nevertheless, G. intestinalis may require heme for the function of particular hemoproteins, such as cytochrome b5 (cytb5). We have analyzed the sequences of eukaryotic cytb5 proteins and identified three distinct cytb5 groups: group I, which consists of C-tail membrane-anchored cytb5 proteins; group II, which includes soluble cytb5 proteins; and group III, which comprises the fungal cytb5 proteins. The majority of eukaryotes possess both group I and II cytb5 proteins, whereas three Giardia paralogs belong to group II. We have identified a fourth Giardia cytb5 paralog (gCYTb5-IV) that is rather divergent and possesses an unusual 134-residue N-terminal extension. Recombinant Giardia cytb5 proteins, including gCYTb5-IV, were expressed in Escherichia coli and exhibited characteristic UV-visible spectra that corresponded to heme-loaded cytb5 proteins. The expression of the recombinant gCYTb5-IV in G. intestinalis resulted in the increased import of extracellular heme and its incorporation into this protein, whereas this effect was not observed when gCYTb5-IV containing a mutated heme-binding site was expressed. The electrons for Giardia cytb5 proteins may be provided by the NADPH-dependent Tah18-like oxidoreductase GiOR-1. Therefore, GiOR-1 and cytb5 may constitute a novel redox system in G. intestinalis. To the best of our knowledge, G. intestinalis is the first anaerobic eukaryote in which the presence of heme has been directly demonstrated

Table_2_Juvenile hormone III induction reveals key genes in general metabolism, pheromone biosynthesis, and detoxification in Eurasian spruce bark beetle.XLSX

IntroductionIn recent years, bark beetle Ips typographus, has caused extensive damage to European Norway spruce forests through widespread outbreaks. This pest employs pheromone-assisted aggregation to overcome tree defense, resulting in mass attacks on host spruce. Many morphological and behavioral processes in I. typographus are under the regulation of juvenile hormone III (JH III), including the biosynthesis of aggregation pheromones and associated detoxification monoterpene conjugates.Objectives and MethodsIn this study, we topically applied juvenile hormone III (JH III) and performed metabolomics, transcriptomics, and proteomics in I. typographus both sexes, with focused aims; 1. Highlight the JH III-regulated metabolic processes; 2. Identify pheromone biosynthesis-linked genes; and 3. Investigate JH III’s impact on detoxification conjugates linked to pheromonal components.ResultsNumerous gene families were enriched after JH III treatment, including genes associated with catalytic and oxidoreductase activity, esterases, phosphatases, and membrane transporters. Sex-specific enrichments for reproduction-related and detoxification genes in females and metabolic regulation genes in males were observed. On the protein level were enriched metal ion binding and transferase enzymes in male beetles. After JHIII treatment, mevalonate pathway genes, including terminal isoprenyl diphosphate synthase (IPDS), were exclusively 35- folds upregulated in males, providing evidence of de novo biosynthesis of pheromone components 2-methyl-3-buten-2-ol and ipsdienol. In addition, cytochrome P450 genes likely involved in the biosynthesis of cis/trans-verbenol, detoxification, and formation of ipsdienol, were 3-fold upregulated in the male gut. The increase in gene expression correlated with the heightened production of the respective metabolites. Detoxification conjugates, verbenyl oleate in the beetle fat body and verbenyl diglycosides in the gut, were induced by JHIII application, which confirms the hormone regulation of their formation. The JH III induction also increased the gene contigs esterase and glycosyl hydrolase up to proteins from male gut tissue. The esterase was proposed to release pheromone cis-verbenol in adult males by breaking down verbenyl oleate. The correlating analyses confirmed a reduction in the abundance of verbenyl oleate in the induced male beetle.ConclusionThe data provide evidence of JH III’s regulatory role in the expression of genes and enzymes related to fundamental beetle metabolism, pheromone biosynthesis, and detoxification in Ips typographus.</p

Table_4_Juvenile hormone III induction reveals key genes in general metabolism, pheromone biosynthesis, and detoxification in Eurasian spruce bark beetle.XLSX

IntroductionIn recent years, bark beetle Ips typographus, has caused extensive damage to European Norway spruce forests through widespread outbreaks. This pest employs pheromone-assisted aggregation to overcome tree defense, resulting in mass attacks on host spruce. Many morphological and behavioral processes in I. typographus are under the regulation of juvenile hormone III (JH III), including the biosynthesis of aggregation pheromones and associated detoxification monoterpene conjugates.Objectives and MethodsIn this study, we topically applied juvenile hormone III (JH III) and performed metabolomics, transcriptomics, and proteomics in I. typographus both sexes, with focused aims; 1. Highlight the JH III-regulated metabolic processes; 2. Identify pheromone biosynthesis-linked genes; and 3. Investigate JH III’s impact on detoxification conjugates linked to pheromonal components.ResultsNumerous gene families were enriched after JH III treatment, including genes associated with catalytic and oxidoreductase activity, esterases, phosphatases, and membrane transporters. Sex-specific enrichments for reproduction-related and detoxification genes in females and metabolic regulation genes in males were observed. On the protein level were enriched metal ion binding and transferase enzymes in male beetles. After JHIII treatment, mevalonate pathway genes, including terminal isoprenyl diphosphate synthase (IPDS), were exclusively 35- folds upregulated in males, providing evidence of de novo biosynthesis of pheromone components 2-methyl-3-buten-2-ol and ipsdienol. In addition, cytochrome P450 genes likely involved in the biosynthesis of cis/trans-verbenol, detoxification, and formation of ipsdienol, were 3-fold upregulated in the male gut. The increase in gene expression correlated with the heightened production of the respective metabolites. Detoxification conjugates, verbenyl oleate in the beetle fat body and verbenyl diglycosides in the gut, were induced by JHIII application, which confirms the hormone regulation of their formation. The JH III induction also increased the gene contigs esterase and glycosyl hydrolase up to proteins from male gut tissue. The esterase was proposed to release pheromone cis-verbenol in adult males by breaking down verbenyl oleate. The correlating analyses confirmed a reduction in the abundance of verbenyl oleate in the induced male beetle.ConclusionThe data provide evidence of JH III’s regulatory role in the expression of genes and enzymes related to fundamental beetle metabolism, pheromone biosynthesis, and detoxification in Ips typographus.</p

Table_1_Juvenile hormone III induction reveals key genes in general metabolism, pheromone biosynthesis, and detoxification in Eurasian spruce bark beetle.XLSX

IntroductionIn recent years, bark beetle Ips typographus, has caused extensive damage to European Norway spruce forests through widespread outbreaks. This pest employs pheromone-assisted aggregation to overcome tree defense, resulting in mass attacks on host spruce. Many morphological and behavioral processes in I. typographus are under the regulation of juvenile hormone III (JH III), including the biosynthesis of aggregation pheromones and associated detoxification monoterpene conjugates.Objectives and MethodsIn this study, we topically applied juvenile hormone III (JH III) and performed metabolomics, transcriptomics, and proteomics in I. typographus both sexes, with focused aims; 1. Highlight the JH III-regulated metabolic processes; 2. Identify pheromone biosynthesis-linked genes; and 3. Investigate JH III’s impact on detoxification conjugates linked to pheromonal components.ResultsNumerous gene families were enriched after JH III treatment, including genes associated with catalytic and oxidoreductase activity, esterases, phosphatases, and membrane transporters. Sex-specific enrichments for reproduction-related and detoxification genes in females and metabolic regulation genes in males were observed. On the protein level were enriched metal ion binding and transferase enzymes in male beetles. After JHIII treatment, mevalonate pathway genes, including terminal isoprenyl diphosphate synthase (IPDS), were exclusively 35- folds upregulated in males, providing evidence of de novo biosynthesis of pheromone components 2-methyl-3-buten-2-ol and ipsdienol. In addition, cytochrome P450 genes likely involved in the biosynthesis of cis/trans-verbenol, detoxification, and formation of ipsdienol, were 3-fold upregulated in the male gut. The increase in gene expression correlated with the heightened production of the respective metabolites. Detoxification conjugates, verbenyl oleate in the beetle fat body and verbenyl diglycosides in the gut, were induced by JHIII application, which confirms the hormone regulation of their formation. The JH III induction also increased the gene contigs esterase and glycosyl hydrolase up to proteins from male gut tissue. The esterase was proposed to release pheromone cis-verbenol in adult males by breaking down verbenyl oleate. The correlating analyses confirmed a reduction in the abundance of verbenyl oleate in the induced male beetle.ConclusionThe data provide evidence of JH III’s regulatory role in the expression of genes and enzymes related to fundamental beetle metabolism, pheromone biosynthesis, and detoxification in Ips typographus.</p

Table_5_Juvenile hormone III induction reveals key genes in general metabolism, pheromone biosynthesis, and detoxification in Eurasian spruce bark beetle.XLSX

IntroductionIn recent years, bark beetle Ips typographus, has caused extensive damage to European Norway spruce forests through widespread outbreaks. This pest employs pheromone-assisted aggregation to overcome tree defense, resulting in mass attacks on host spruce. Many morphological and behavioral processes in I. typographus are under the regulation of juvenile hormone III (JH III), including the biosynthesis of aggregation pheromones and associated detoxification monoterpene conjugates.Objectives and MethodsIn this study, we topically applied juvenile hormone III (JH III) and performed metabolomics, transcriptomics, and proteomics in I. typographus both sexes, with focused aims; 1. Highlight the JH III-regulated metabolic processes; 2. Identify pheromone biosynthesis-linked genes; and 3. Investigate JH III’s impact on detoxification conjugates linked to pheromonal components.ResultsNumerous gene families were enriched after JH III treatment, including genes associated with catalytic and oxidoreductase activity, esterases, phosphatases, and membrane transporters. Sex-specific enrichments for reproduction-related and detoxification genes in females and metabolic regulation genes in males were observed. On the protein level were enriched metal ion binding and transferase enzymes in male beetles. After JHIII treatment, mevalonate pathway genes, including terminal isoprenyl diphosphate synthase (IPDS), were exclusively 35- folds upregulated in males, providing evidence of de novo biosynthesis of pheromone components 2-methyl-3-buten-2-ol and ipsdienol. In addition, cytochrome P450 genes likely involved in the biosynthesis of cis/trans-verbenol, detoxification, and formation of ipsdienol, were 3-fold upregulated in the male gut. The increase in gene expression correlated with the heightened production of the respective metabolites. Detoxification conjugates, verbenyl oleate in the beetle fat body and verbenyl diglycosides in the gut, were induced by JHIII application, which confirms the hormone regulation of their formation. The JH III induction also increased the gene contigs esterase and glycosyl hydrolase up to proteins from male gut tissue. The esterase was proposed to release pheromone cis-verbenol in adult males by breaking down verbenyl oleate. The correlating analyses confirmed a reduction in the abundance of verbenyl oleate in the induced male beetle.ConclusionThe data provide evidence of JH III’s regulatory role in the expression of genes and enzymes related to fundamental beetle metabolism, pheromone biosynthesis, and detoxification in Ips typographus.</p