scholarly journals Iron is not everything: unexpected complex metabolic responses between iron-cycling microorganisms

2020 ◽  
Vol 14 (11) ◽  
pp. 2675-2690
Author(s):  
Rebecca E. Cooper ◽  
Carl-Eric Wegner ◽  
Stefan Kügler ◽  
Remington X. Poulin ◽  
Nico Ueberschaar ◽  
...  

Abstract Coexistence of microaerophilic Fe(II)-oxidizers and anaerobic Fe(III)-reducers in environments with fluctuating redox conditions is a prime example of mutualism, in which both partners benefit from the sustained Fe-pool. Consequently, the Fe-cycling machineries (i.e., metal-reducing or –oxidizing pathways) should be most affected during co-cultivation. However, contrasting growth requirements impeded systematic elucidation of their interactions. To disentangle underlying interaction mechanisms, we established a suboxic co-culture system of Sideroxydans sp. CL21 and Shewanella oneidensis. We showed that addition of the partner’s cell-free supernatant enhanced both growth and Fe(II)-oxidizing or Fe(III)-reducing activity of each partner. Metabolites of the exometabolome of Sideroxydans sp. CL21 are generally upregulated if stimulated with the partner´s spent medium, while S. oneidensis exhibits a mixed metabolic response in accordance with a balanced response to the partner. Surprisingly, RNA-seq analysis revealed genes involved in Fe-cycling were not differentially expressed during co-cultivation. Instead, the most differentially upregulated genes included those encoding for biopolymer production, lipoprotein transport, putrescine biosynthesis, and amino acid degradation suggesting a regulated inter-species biofilm formation. Furthermore, the upregulation of hydrogenases in Sideroxydans sp. CL21 points to competition for H2 as electron donor. Our findings reveal that a complex metabolic and transcriptomic response, but not accelerated formation of Fe-end products, drive interactions of Fe-cycling microorganisms.

2021 ◽  
Vol 22 (5) ◽  
pp. 2746
Author(s):  
Dimitri Shcherbakov ◽  
Reda Juskeviciene ◽  
Adrián Cortés Sanchón ◽  
Margarita Brilkova ◽  
Hubert Rehrauer ◽  
...  

Mitochondrial misreading, conferred by mutation V338Y in mitoribosomal protein Mrps5, in-vivo is associated with a subtle neurological phenotype. Brain mitochondria of homozygous knock-in mutant Mrps5V338Y/V338Y mice show decreased oxygen consumption and reduced ATP levels. Using a combination of unbiased RNA-Seq with untargeted metabolomics, we here demonstrate a concerted response, which alleviates the impaired functionality of OXPHOS complexes in Mrps5 mutant mice. This concerted response mitigates the age-associated decline in mitochondrial gene expression and compensates for impaired respiration by transcriptional upregulation of OXPHOS components together with anaplerotic replenishment of the TCA cycle (pyruvate, 2-ketoglutarate).


2019 ◽  
Vol 26 (11) ◽  
pp. 1485-1492
Author(s):  
Xiaochun Yi ◽  
Jie Zhang ◽  
Huixiang Liu ◽  
Tianxia Yi ◽  
Yuhua Ou ◽  
...  

The adverse clinical result and poor treatment outcome in recurrent spontaneous abortion (RSA) make it necessary to understand the pathogenic mechanism. The mating combination CBA/J × DBA/2 has been widely used as an abortion-prone model compared to DBA/2-mated CBA/J mice. Here, we used RNA-seq to get a comprehensive catalogue of genes differentially expressed between survival placenta in abortion-prone model and control. Five hundred twenty-four differentially expressed genes were obtained followed by clustering analysis, Gene Ontology analysis, and pathway analysis. We paid more attention to immune-related genes namely “immune response” and “immune system process” including 33 downregulated genes and 28 upregulated genes. Twenty-one genes contribute to suppressing immune system and 7 are against it. Six genes were validated by reverse transcription-polymerase chain reaction, namely Ccr1l1, Tlr4, Tgf-β1, Tyro3, Gzmb, and Il-1β. Furthermore, Tlr4, Tgf-β1, and Il-1β were analyzed by Western blot. Such immune profile gives us a better understanding of the complicated immune processing in RSA and immunosuppression can rescue pregnancy loss.


BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Clemens Falker-Gieske ◽  
Andrea Mott ◽  
Sören Franzenburg ◽  
Jens Tetens

Abstract Background Retinol (RO) and its active metabolite retinoic acid (RA) are major regulators of gene expression in vertebrates and influence various processes like organ development, cell differentiation, and immune response. To characterize a general transcriptomic response to RA-exposure in vertebrates, independent of species- and tissue-specific effects, four publicly available RNA-Seq datasets from Homo sapiens, Mus musculus, and Xenopus laevis were analyzed. To increase species and cell-type diversity we generated RNA-seq data with chicken hepatocellular carcinoma (LMH) cells. Additionally, we compared the response of LMH cells to RA and RO at different time points. Results By conducting a transcriptome meta-analysis, we identified three retinoic acid response core clusters (RARCCs) consisting of 27 interacting proteins, seven of which have not been associated with retinoids yet. Comparison of the transcriptional response of LMH cells to RO and RA exposure at different time points led to the identification of non-coding RNAs (ncRNAs) that are only differentially expressed (DE) during the early response. Conclusions We propose that these RARCCs stand on top of a common regulatory RA hierarchy among vertebrates. Based on the protein sets included in these clusters we were able to identify an RA-response cluster, a control center type cluster, and a cluster that directs cell proliferation. Concerning the comparison of the cellular response to RA and RO we conclude that ncRNAs play an underestimated role in retinoid-mediated gene regulation.


Author(s):  
Bryn Short ◽  
Christopher Delaney ◽  
Emily McKloud ◽  
Jason L. Brown ◽  
Ryan Kean ◽  
...  

Candida albicans is an opportunistic pathogen found throughout multiple body sites and is frequently co-isolated from infections of the respiratory tract and oral cavity with Staphylococcus aureus. Herein we present the first report of the effects that S. aureus elicits on the C. albicans transcriptome. Dual-species biofilms containing S. aureus and C. albicans mutants defective in ALS3 or ECE1 were optimised and characterised, followed by transcriptional profiling of C. albicans by RNA-sequencing (RNA-seq). Altered phenotypes in C. albicans mutants revealed specific interaction profiles between fungus and bacteria. The major adhesion and virulence proteins Als3 and Ece1, respectively, were found to have substantial effects on the Candida transcriptome in early and mature biofilms. Despite this, deletion of ECE1 did not adversely affect biofilm formation or the ability of S. aureus to interact with C. albicans hyphae. Upregulated genes in dual-species biofilms corresponded to multiple gene ontology terms, including those attributed to virulence, biofilm formation and protein binding such as ACE2 and multiple heat-shock protein genes. This shows that S. aureus pushes C. albicans towards a more virulent genotype, helping us to understand the driving forces behind the increased severity of C. albicans-S. aureus infections.


2019 ◽  
Author(s):  
Hoang T. M. D. Le ◽  
Kai K. Lie ◽  
Angela Etayo ◽  
Ivar Rønnestad ◽  
Øystein Sæle

AbstractThe transcriptome of nutrient sensing and the regulation of gut motility by nutrients in a stomachless fish with a short digestive tract; the ballan wrasse (Labrus berggylta) were investigated. Using an in vitro model, we differentiate how signals initiated by physical stretch and nutrients modulate the gut evacuation rate and motility patterns, and transcriptomic changes. Stretch on the intestine by inert cellulose initiated fast evacuation out of the anterior intestine compared to the digestible protein and lipid. Stretch on the intestine upregulated genes associated with increased muscle activity, whereas nutrients stimulated pathways related to ribosomal activity and the increase in the expression of several neuropeptides which are directly involved in gut motility regulation. Our findings show that physical pressure in the intestine initiate contractions propelling the matter towards the exit, whereas the sensing of nutrients modulates the motility to prolong the residence of digesta in the digestive tract for optimal digestion.Summary statementPressure by food speed up peristalsis in the intestine, but the intestines ability to sense nutrients slow down peristalsis for better digestion. This is partly controlled by genetic regulation.


Plants ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 214
Author(s):  
Qinghui Han ◽  
Qingxiang Zhu ◽  
Yao Shen ◽  
Michael Lee ◽  
Thomas Lübberstedt ◽  
...  

Chilling injury poses a serious threat to seed emergence of spring-sowing maize in China, which has become one of the main climatic limiting factors affecting maize production in China. It is of great significance to mine the key genes controlling low-temperature tolerance during seed germination and study their functions for breeding new maize varieties with strong low-temperature tolerance during germination. In this study, 176 lines of the intermated B73 × Mo17 (IBM) Syn10 doubled haploid (DH) population, which comprised 6618 bin markers, were used for QTL analysis of low-temperature germination ability. The results showed significant differences in germination related traits under optimum-temperature condition (25 °C) and low-temperature condition (10 °C) between two parental lines. In total, 13 QTLs were detected on all chromosomes, except for chromosome 5, 7, 10. Among them, seven QTLs formed five QTL clusters on chromosomes 1, 2, 3, 4, and 9 under the low-temperature condition, which suggested that there may be some genes regulating multiple germination traits at the same time. A total of 39 candidate genes were extracted from five QTL clusters based on the maize GDB under the low-temperature condition. To further screen candidate genes controlling low-temperature germination, RNA-Seq, in which RNA was extracted from the germination seeds of B73 and Mo17 at 10 °C, was conducted, and three B73 upregulated genes and five Mo17 upregulated genes were found by combined analysis of RNA-Seq and QTL located genes. Additionally, the variations of Zm00001d027976 (GLABRA2), Zm00001d007311 (bHLH transcription factor), and Zm00001d053703 (bZIP transcription factor) were found by comparison of amino sequence between B73 and Mo17. This study will provide a theoretical basis for marker-assisted breeding and lay a foundation for further revealing molecular mechanism of low-temperature germination tolerance in maize.


2019 ◽  
Author(s):  
İrem Çelen ◽  
Aroshan Jayasinghe ◽  
Jung H. Doh ◽  
Chandran R. Sabanayagam

AbstractBackgroundGiven the growing interest in human exploration of space, it is crucial to identify the effect of space conditions on biological processes. The International Space Station (ISS) greatly helps researchers determine these effects. However, the impact of the ISS-introduced potential confounders (e.g., the combination of radiation and microgravity exposures) on the biological processes are often neglected, and separate investigations are needed to uncover the impact of individual conditions.ResultsHere, we analyze the transcriptomic response of Caenorhabditis elegans to simulated microgravity and observe the maintained transcriptomic response after return to ground conditions for four, eight, and twelve days. Through the integration of our data with those in NASA GeneLab, we identify the gravitome, which we define as microgravity-responsive transcriptomic signatures. We show that 75% of the simulated microgravity-induced changes on gene expression persist after return to ground conditions for four days while most of these changes are reverted after twelve days return to ground conditions. Our results from integrative RNA-seq and mass spectrometry analyses suggest that simulated microgravity affects longevity regulating insulin/IGF-1 and sphingolipid signaling pathways.ConclusionsOur results address the sole impact of simulated microgravity on transcriptome by controlling for the other space-introduced conditions and utilizing RNA-seq. Using an integrative approach, we identify a conserved transcriptomic signature to microgravity and its sustained impact after return to the ground. Moreover, we present the effect of simulated microgravity on distinct ceramide profiles. Overall, this work can provide insights into the sole effect of microgravity on biological systems.


2020 ◽  
pp. 160-170
Author(s):  
John Vivian ◽  
Jordan M. Eizenga ◽  
Holly C. Beale ◽  
Olena M. Vaske ◽  
Benedict Paten

PURPOSE Many antineoplastics are designed to target upregulated genes, but quantifying upregulation in a single patient sample requires an appropriate set of samples for comparison. In cancer, the most natural comparison set is unaffected samples from the matching tissue, but there are often too few available unaffected samples to overcome high intersample variance. Moreover, some cancer samples have misidentified tissues of origin or even composite-tissue phenotypes. Even if an appropriate comparison set can be identified, most differential expression tools are not designed to accommodate comparisons to a single patient sample. METHODS We propose a Bayesian statistical framework for gene expression outlier detection in single samples. Our method uses all available data to produce a consensus background distribution for each gene of interest without requiring the researcher to manually select a comparison set. The consensus distribution can then be used to quantify over- and underexpression. RESULTS We demonstrate this method on both simulated and real gene expression data. We show that it can robustly quantify overexpression, even when the set of comparison samples lacks ideally matched tissue samples. Furthermore, our results show that the method can identify appropriate comparison sets from samples of mixed lineage and rediscover numerous known gene-cancer expression patterns. CONCLUSION This exploratory method is suitable for identifying expression outliers from comparative RNA sequencing (RNA-seq) analysis for individual samples, and Treehouse, a pediatric precision medicine group that leverages RNA-seq to identify potential therapeutic leads for patients, plans to explore this method for processing its pediatric cohort.


Sign in / Sign up

Export Citation Format

Share Document