Biology subjects

Du, Y.

Publications and source records attributed to Du, Y..

At least 253 records · Page 14Linked to original sources

bioRxiv2021

Establishment of a closed artificial ecosystem to ensure human long-term survival on the moon

Bioregenerative life support system (BLSS) is a critical technology maintaining long-term human survival on the Moon or other extraterrestrial bodies. In the current study, we carried out a 370-day integrated high-closure experiment ("Lunar Palace 365" experiment) on the Earth in an upgraded ground-based BLSS experimental facility called "Lunar Palace 1". This experiment was designed to develop techniques to run and adjust system stability under long-term operation and crew shift change conditions. Eight volunteering crew members were divided into two groups with three time phases: Group I stayed in the cabin for the initial 60-day phase; Group II inhabited the cabin instead for a record-breaking duration of 200 days as the second phase; Group I re-entered the cabin, replaced Group II and stayed for the last 105 days. Our results demonstrated the BLSS had excellent stability with a material closure degree of 98.2%. Levels of O2, CO2 and trace harmful gases were well controlled within ranges optimal for crew health and plant production. The system exhibited a strong robustness and could quickly minimize effects of disturbances through self-feedback adjustments. The efficiency of plant production completely met the crews need of plant-based food. The purification efficiency of domestic and sanitary wastewater was up to irrigation standards, and the recovery rate of urine and solid waste achieved 99.7% and 67%, respectively. These results are valuable for further optimization of the BLSS in a lunar base and computer simulations of similar systems.

ecology↗

bioRxiv2021

All-Flesh Tomato Regulated by Reduced Dosage of AFF Provides New Insights into Berry Fruit Evolution

The formation of locule gel is not only an important developmental process in tomato but also a typical characteristic of berry fruit. In this study, we collected a tomato material that produces all-flesh fruits (AFF), whose locule tissue remains in a solid state during fruit development. We built genetic populations to fine map the causal gene of AFF trait, investigate the function of AFF gene, and identified it as the causal locus conferring the locule gel formation. We determined the causal mutation as a 416-bp deletion that occurred in the promoter region of AFF, which reduces the expression dosage of AFF. The 416-bp deleted sequence has a high level of conservation among closely related Solanaceae species, as well as in the tomato population. The activity of the 416-bp deletion in down-regulating gene expression was further verified by the relative activity in a luciferase experiment. Furthermore, with the BC6 NIL materials, we reveal that the reduced expression dosage of AFF does not impact the normal development of seeds, while produces non-liquefied locule tissue, which is distinct from that of the normal tomatoes in terms of metabolic components. Based on these findings, we propose that the AFF gene is the core node in locule tissue liquefaction, whose function cannot be compensated by its paralogs TAG1, TAGL1, or TAGL11. Our findings provide clues to investigate fruit type differentiation among Solanaceae crops, and also contributes to the breeding application of all flesh fruit tomatoes for the tomato processing industry. One Sentence SummaryThe sequence deletion that occurred in the cis-regulatory region of AFF--the core node of locule tissue liquefaction determined here--reduced its expression dosage, and produced all flesh fruit tomato.

plant biology↗

bioRxiv2021

Disrupted dynamic functional network connectivity among cognitive control networks in the progression of Alzheimer's disease

BackgroundAlzheimers disease (AD) is the most common age-related dementia that promotes a decline in memory, thinking, and social skills. The initial stages of dementia can be associated with mild symptoms, and symptom progression to a more severe state is heterogeneous across patients. Recent work has demonstrated the potential for functional network mapping to assist in the prediction of symptomatic progression. However, this work has primarily used static functional connectivity (sFC) from rs-fMRI. Recently, dynamic functional connectivity (dFC) has been recognized as a powerful advance in functional connectivity methodology to differentiate brain network dynamics between healthy and diseased populations. MethodsGroup independent component analysis was applied to extract 17 components within the cognitive control network (CCN) from 1385 individuals across varying stages of AD symptomology. We estimated dFC among 17 components within the CCN, followed by clustering the dFCs into 3 recurring brain states and then estimated a hidden Markov model and the occupancy rate for each subject. Finally, we investigated the link between CCN dFC connectivity features with AD progression. ResultsProgression of AD symptoms were associated with increases in connectivity within the middle frontal gyrus. Also, the AD with mild and severer symptoms showed less connectivity within the inferior parietal lobule and between this region with the rest of CCN. Finally, comparing with mild dementia, we found that the normal brain spends significantly more time in a state with lower within middle frontal gyrus connectivity and higher connectivity between the hippocampus and the rest of CCN, highlighting the importance of assessing the dynamics of brain connectivity in this disease. ConclusionOur results suggest that AD progress not only alters the CCN connectivity strength but also changes the temporal properties in this brain network. This suggests the temporal and spatial pattern of CCN as a biomarker that differentiates different stages of AD. Impact StatementBy assuming that functional connectivity is static over time, many of previous studies have ignored the brain dynamic in Alzheimers disease progression. Here, a longitudinal resting-state functional magnetic resonance imaging data are used to explore the temporal changes of functional connectivity in the cognitive control network in Alzheimers disease progression. The result of this study would increase our understanding about the underlying mechanisms of Alzheimers Disease and help in finding future treatment of this neurological disorder.

neuroscience↗

bioRxiv2020

Trans-Golgi network-lipid droplet contacts maintain the TGN integrity and function via lipid transfer activities of VPS13B

While the physical interactions between the Golgi apparatus (Golgi) and lipid droplets (LDs) have been suggested through system-level imaging, the bona fide and functional Golgi-LD membrane contact sites (MCSs) remain largely uncharacterized. Here, we demonstrate that vacuolar protein sorting-associated protein 13B (VPS13B) mediates trans-Golgi network (TGN)-LD interactions. VPS13B is specifically accumulated at TGN-LD MCSs with its C-terminal region targeting LDs via an amphipathic helix while a putative WD40 module and a C-terminal Pleckstrin homology (PH) domain independently recognizing TGN via directly binding to Rab6. A putative lipid transfer domain (LTD) at the N-terminal portion of VPS13B binds glycerophospholipids in vitro. VPS13B suppression results in severe fragmentation of the TGN, an effect that can be almost completely rescued by the expression of VPS13B-LTD. Collectively, our findings demonstrate that VPS13B mediates lipid transfer at TGN-LD MCSs to maintain TGN integrity and function.

cell biology↗

bioRxiv2020

Data-informed discovery of hydrolytic nanozymes

Nanozyme is a collection of nanomaterials with enzyme-like activity but exhibits higher environmental tolerance and long-term stability than their natural counterparts. Improving the catalytic activity and expanding the category of nanozymes are prerequisites to complement or even supersede natural enzymes. Specifically, a powerful hydrolytic nanozyme is demanded to degrade the unsustainable substance which natural enzymes hardly achieve. However, the development of hydrolytic nanozymes is still hindered by diverse hydrolytic substrates and following complicated mechanisms. Here, we apply two strategies which are informed by data to screen and predict catalytic active sites of MOF (metal-organic framework) based hydrolytic nanozymes. One is to increase the intrinsic activity by finely tuned Lewis acidity of the metal clusters. The other is to adjust the volume density of the active sites by shortening the length of ligands. Finally, we construct a Ce-FMA-MOF-based hydrolytic nanozyme with robust cleavage ability towards phosphate bonds, amide bonds, glycosidic bonds whose energy ascend in order; and even their mixture, biofilms. This work provides a rational methodology to design hydrolytic nanozyme, enriches the diversity of nanozymes, and potentially sheds a light on the evolution of enzyme engineering in the future.

biophysics↗

bioRxiv2020

Deletion of Letmd1 leads to the disruption of mitochondrial function in brown adipose tissue

Human cervical cancer oncogene (HCCR-1), also named as LETMD1, is a LETM-domain containing outer mitochondrial membrane protein which plays an important role in the carcinogenesis of cancers. Surprisingly, we found that loss of Letmd1 in mice leads to multiply severe abnormities, such as the brown adipose tissue (BAT) whitening, disruption of thermogenesis, cold-induced death, diet-induced obesity, hyperglycinemia and insulin resistance. Mechanistically, deletion of Letmd1 in BAT causes the reduction of mitochondrial calcium ion, which in turn results in the suppressed fission of mitochondria, and ultimately leads to the depletion of Ucp1-mediated BAT heat production. This study indicates that LETMD1 plays a crucial role in controlling BAT thermogenesis and energy homeostasis by regulating mitochondrial structures and functions, and also provides a novel insight for the clinical biomarker and therapeutical target of oncogene for the metabolic disorders. HighlightsO_LILetmd1 is an oncogene and also highly expressed in brown adipose tissue (BAT) of human and mice. C_LIO_LILoss of Letmd1 leads to BAT whitening, diet-induced obesity, hyperglycemia and insulin resistant. C_LIO_LILetmd1 knockout causes the disruption of thermogenesis and death at 4{degrees}C exposure. C_LIO_LIDeletion of Letmd1 results in mitochondrial calcium homeostasis disorders. C_LI Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=159 HEIGHT=200 SRC="FIGDIR/small/388199v2_ufig1.gif" ALT="Figure 1"> View larger version (65K): org.highwire.dtl.DTLVardef@bee6adorg.highwire.dtl.DTLVardef@11a7cc1org.highwire.dtl.DTLVardef@1f4699forg.highwire.dtl.DTLVardef@142699a_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

bioRxiv2020

Ultrastructural view of astrocyte-astrocyte and astrocyte-synapse contacts within the hippocampus

Astrocytes branch out and make contact at their interfaces. However, the ultrastructural interactions of astrocytes and astrocytes with their surroundings, including the spatial-location selectivity of astrocyte-synapse contacts, remain unknown. Here, the branching architecture of three neighboring astrocytes, their contact interfaces, and their surrounding neurites and synapses have been traced and 3D reconstructed using serial block-face scanning electron microscopy (SBF-SEM). Our reconstructions reveal extensive reflexive, loop-like processes that serve as scaffolds to neurites and give rise to spongiform astrocytic morphology. At the astrocyte-astrocyte interface, a cluster of process-process contacts were identified, which biophysically explains the existence of low inter-astrocytic electrical resistance. Additionally, we found that synapses uniformly made contact with the entire astrocyte, from soma to terminal processes, and can be ensheathed by two neighboring astrocytes. Lastly, in contrast to densely packed vesicles at the synaptic boutons, vesicle-like structures were scant within astrocytes. Together, these ultrastructural details should expand our understanding of functional astrocyte-astrocyte and astrocyte-neuron interactions.

neuroscience↗

bioRxiv2020

Deciphering the mechanism underlying circRNA-mediated immune responses of western honeybees to Nosema ceranae infection

Nosema ceranae is a widespread fungal parasite for adult honeybees, severely damaging bee health and sustainable development of apiculture. Circular RNAs (circRNAs) are a class of newly discovered noncoding RNAs (ncRNAs) that regulate a number of biological processes such as immune defense and development. In this current work, based on previously obtained whole transcriptome data, 8 199 and 8 711 circRNAs were predicted from the midguts of Apis mellifera ligustica workers at 7 days (AmT1) and 10 days (AmT2) post inoculation (dpi) with N. ceranae using bioinformatics. Additionally, in combination with transcriptome data from uninfected midguts (AmCK1 and AmCK2) (Xiong et al., 2018), 4 464 circRNAs were found to be shared by the aforementioned four groups, whereas the numbers of specifically transcribed circRNAs in each group were 1 389, 1 696, 1 019 and 1 871, respectively. Furthermore, 10 226 circRNAs were homologous to Apis cerana cerana circRNAs, while 20 circRNAs had homology with Homo sapiens circRNAs; in addition, 16 circRNAs were highly conserved in these three species. Differential expression analysis showed that 168 (306) differentially expressed circRNAs (DEcircRNAs) were identified in AmCK1 vs AmT1 (AmCK2 vs AmT2) comparison group, including 61 (143) upregulated circRNAs and 107 (163) downregulated circRNAs. Moreover, RT-qPCR results showed that the expression trend of eight DEcircRNAs was consistent with that of the transcriptome dataset. Based on GO database annotation, we observed that source genes of DEcircRNAs in AmCK1 vs AmT1 (AmCK2 vs AmT2) were engaged in 27 (35) functional terms, including two (two) cell renewal-associated terms, seven (seven) cell structure-associated terms, and one (one) immunity-associated terms. Additionally, DEcircRNA source genes in AmCK1 vs AmT1 were involved in two cell renewal-related pathways, Hippo and Wnt signaling pathways, and three carbohydrate metabolism-related pathways, galactose metabolism, starch and sucrose metabolism, fructose and mannose metabolism, only one energy metabolism-related pathway (oxidative phosphorylation pathway), three cellular immune-related pathways, endocytosis, phagosome, and lysosome, and a humoral immune-related pathway (FoxO signaling pathway). In AmCK2 vs AmT2 comparison group, more source genes of DEcircRNAs were associated with the abovementioned pathways relative to cell renewal, carbohydrate metabolism, and cellular and humoral immune pathways. In addition, 122 (234) DEcircRNAs in the host midgut at 7 dpi (10 dpi) with N. ceranae targeted 82 (106) miRNAs. Furthermore, 75 (103) miRNAs targeted by 86 (178) DEcircRNAs in AmCK1 vs AmT1 (AmCK2 vs AmT2) further bound to 215 (305) mRNAs. These targets could be annotated as an array of functional terms and pathways related to cellular renewal, cellular structure, carbohydrate and energy metabolism, and cellular and humoral immunity. In a word, we for the first time explored immune responses mediated by DEcircRNAs in the midguts of A. m. ligustica workers to N. ceranae infection. Our data provide a foundation for clarifying the molecular mechanism underlying immune response of western honeybee to N. ceranae invasion, but also a new insight into further understanding the host-pathogen interaction during bee microsporidiosis.

genomics↗

bioRxiv2020

Potential Linkage between Toxoplasma gondii Infection and Physical Education Scores of College Students

ObjectiveToxoplasma gondii is a worldwide protozoan parasite that could infect virtually all warm-blooded animals, including humans. Our study aimed to investigate the prevalence of T. gondii infection in college students at Anhui province, China. Moreover, growing studies demonstrated the association between T. gondii infection and host behavioral changes. We also studied the linkage between T. gondii and scores of college students. Methods2704 serum samples of medical school students attending physical education lessons were collected from September 2017 to September 2019 and evaluated for T. gondii IgG antibodies using an enzyme-linked immunosorbent assay (ELISA). We also analysed PE scores of T. gondii infected students and T. gondii uninfected students. ResultsThe overall seroprevalence of T. gondii was 11.5%. The main risk factors related to T. gondii infections were cat in the household and gardening or agriculture activity. Furthermore, in basketball group and football group, scores of T. gondii seropositive students were significantly higher than that of seronegative students, while in other sports there is no difference between scores of T. gondii infected students and T. gondii uninfected students. ConclusionThis is the first report of T. gondii seroprevalence in college students in Anhui province, China.

microbiology↗

bioRxiv2020

Programmable Aggregation of Artificial Cells with DNA Signals

Cell aggregation is a complex behavior, which is closely related to the viability, differentiation, and migration of cells. An effort to create synthetic analogs could lead to considerable advances in cell physiology and biophysics. Rendering and modulating such a dynamic artificial cell system require mechanisms for receiving, transducing, and transmitting intercellular signals, yet effective tools are limited at present. Here we construct synthetic cells from engineered lipids and show their programmable aggregation behaviors using DNA oligonucleotides as a signaling molecule. The artificial cells have transmembrane channels made of DNA origami that are used to recognize and process intercellular signals. We demonstrate that multiple small vesicles aggregate onto a giant vesicle after a transduction of external DNA signals by an intracellular enzyme, and that the small vesicles dissociate when receiving release signals. This work provides new possibilities for building synthetic protocells capable of chemical communication and coordination.

synthetic biology↗

bioRxiv2020

Automatic Measurement of Inner Ear in Different Mammals

ObjectiveTo facilitate the selection of optimal animal models for noise-induced hearing loss (NIHL) research, this study aims to develop an accurate, automatic centerline-based method to construct three-dimensional (3D) inner ear models in various mammals and assess their morphological similarities to humans. MethodsThree adult mice, three guinea pigs, three mini pigs, and one human temporal bone were scanned using Micro-CT. After segmentation, 3D inner ear models were reconstructed. A novel centerline method was established to automatically estimate 3D properties and calculate length, volume, and angle parameters across species. ResultsDetailed 3D models of the cochlea, vestibule, and semicircular canals were successfully constructed. Mean lengths and volumes of the cochlea and semicircular canals generally increased with body size, with mini pigs demonstrating the closest proximity to human data. Notably, numerical assessments showed that the semicircular canals in both mice and mini pigs closely resembled human structures. ConclusionAutomatic centerline-based measurement provides an effective tool for assessing 3D inner ear morphology. By confirming the high morphological similarity between mini pigs and humans, this study provides a critical theoretical basis for the mechanical analysis of noise-induced damage and the selection of biomimetic animal models for NIHL studies.

neuroscience↗

bioRxiv2020

Cryo-EM structure of yeast 90S preribosome at 3.4 Angstrom resolution

Previously, we determined a cryo-EM structure of Saccharomyces cerevisiae 90S preribosome obtained after depletion of the RNA helicase Mtr4 at 4.5 [A] resolution (Sun et al., 2017). The 90S preribosome is an early assembly intermediate of small ribosomal subunit. Here, the structure was improved to 3.4 [A] resolution and reveals many previously unresolved structures and interactions, in particular around the central domain of 18S rRNA. The central domain adopts a closed conformation in our structure, in contrast to an open conformation in another high-resolution structure of S. cerevisiae 90S. The new model of 90S would serve as a better reference for investigation of the assembly mechanism of small ribosomal subunit.

biophysics↗

bioRxiv2020

The soybean Rhg1 amino acid transporter protein becomes abundant along the SCN penetration path and impacts ROS generation

Rhg1 mediates soybean resistance to soybean cyst nematode. Glyma.18G022400, one of three resistance-conferring genes at the complex Rhg1 locus, encodes the putative amino acid transporter AATRhg1 whose mode of action is largely unknown. We discovered that AATRhg1 protein abundance increases 7- to 15-fold throughout root cells penetrated by SCN. These root cells develop increased abundance of vesicles and larger vesicle-like bodies. AATRhg1 was often associated with these vesicles. AATRhg1 abundance remained low in syncytia (plant reprogrammed feeding cells), unlike the Rhg1 -SNAP protein whose abundance was previously shown to increase in syncytia. In N. benthamiana, if soybean AATRhg1 was present, oxidative stress promoted formation of larger macrovesicles and they contained AATRhg1. AATRhg1 was found to interact with GmRBOHC2, a soybean ortholog of Arabidopsis RBOHD previously found to exhibit upregulated expression upon SCN infection. Reactive oxygen species (ROS) generation was more elevated when AATRhg1 and GmRBOHC2 abundance were co-expressed. These findings suggest that AATRhg1 contributes to SCN resistance along the penetration path as SCN invades the plant, and does so at least in part by interactions with GmRBOHC2 that increase ROS production. The study also shows that Rhg1 resistance functions via at least two spatially and temporally separate modes of action.

plant biology↗

bioRxiv2020

Degradation of ATFS-1 by LONP-1 promotes deleterious mitochondrial genome heteroplasmy

The accumulation of deleterious mitochondrial genomes ({Delta}mtDNAs) underlies inherited mitochondrial diseases and contributes to the aging-associated decline in mitochondrial function. In heteroplasmic cells, oxidative phosphorylation (OXPHOS) function declines as the population of {Delta}mtDNAs increase relative to wildtype mtDNAs. In response to mitochondrial perturbations, the bZIP protein ATFS-1 induces a transcription program to promote the recovery of mitochondrial function. Paradoxically, ATFS-1 is also required to maintain {Delta}mtDNAs in heteroplasmic worms. However, the mechanism(s) by which ATFS-1 promotes {Delta}mtDNA accumulation relative to wildtype mtDNAs is unclear. Here, we show that mitochondrial-localized ATFS-1 binds almost exclusively to {Delta}mtDNAs in heteroplasmic worms. Moreover, we demonstrate that mitochondrial ATFS-1 promotes the preferential binding of the mtDNA replicative polymerase (POLG) to {Delta}mtDNAs. Interestingly, inhibition of the mtDNA-bound protease LONP-1 increased ATFS-1 and POLG binding to wildtype mtDNAs. Furthermore, LONP-1 inhibition in C. elegans and human cybrid cells improved the heteroplasmy ratio and restored OXPHOS function. Our findings suggest that ATFS-1 promotes mtDNA replication by recruiting POLG to mtDNA in a manner that is antagonized by LONP-1. We speculate that this mechanism promotes the repair and expansion of the mitochondrial network by synchronizing mtDNA replication with UPRmt activation driven by nuclear ATFS-1 activity. However, this repair mechanism cannot resolve OXPHOS defects in mitochondria harboring {Delta}mtDNAs, resulting in an accumulation of ATFS-1 in dysfunctional mitochondria and constitutive replication of {Delta}mtDNAs.

cell biology↗

bioRxiv2020

Mutanofactin promotes bacterial adhesion and biofilm formation of cariogenic Streptococcus mutans

Cariogenic Streptococcus mutans is known as a predominant etiological agent of dental caries due to its exceptional capacity in forming biofilms. From strains of S. mutans isolated from dental plaque, we here discover a polyketide/non-ribosomal peptide biosynthetic gene cluster, muf, which directly correlates with a strong biofilm-forming capability. We then identify the muf-associated bioactive product, mutanofactin-697 that contains a novel molecular scaffold, along with its biosynthetic logic. Further mode-of-action studies reveal mutanofactin-697 binds to S. mutans cells nonspecifically, increases bacterial hydrophobicity, and promotes bacterial adhesion and subsequent biofilm formation. Our findings provide the first example of a microbial secondary metabolite promoting biofilm formation via a physicochemical approach, highlighting the significance of secondary metabolism in mediating critical processes related to the development of dental caries.

microbiology↗

bioRxiv2020

Tumor Immunity Microenvironment-based classifications of bladder cancer for enhancing cancer immunotherapy

BackgroundBladder cancer is composed by a mass of heterogenetic characteristics, immunotherapy is a potential way to save the life of bladder cancer patients, but only benefit to about 20% patients. Methods and materialsA total of 4003 bladder cancer patients from 19 cohorts was enrolled in this study, collecting the clinical information and mRNA expression profile. The unsupervised non-negative matrix factorization (NMF) and nearest template prediction (NTP) algorithm was used to divide the patients to immune activated, immune exhausted and non-immune class. Verified gene sets of signatures were used to illustrate the characteristic of immunophenotypes. Clinical and genetic features were compared in different immunophenotypes. ResultsWe identified the immune class and non-immune classes in from TCGA-BLCA cohort. The 150 top different expression genes between these two classes was extracted as the input profile for the reappearing of the classification in the other 19 cohorts. As to the activated and exhausted subgroups, a stromal activation signature was conducted by NTP algorithm. Patients in the immune classes shown the highly enriched signatures of immunocytes, while the exhausted subgroup also shown an increased signature of TITR, WNT/TGF-{beta}, TGF-{beta}1 activated, and C-ECM signatures. Patients in the immune activated shown a lower CNA burden, better overall survival, and favorable response to anti-PD-1 therapy. ConclusionWe defined and validated a novel classifier among the 4003 bladder cancer patients. Anti-PD-1 immunotherapy could benefit more for the patients belong to immune activated subgroup, while ICB therapy plus TGF-{beta} inhibitor or EP300 inhibitor might be more effectiveness for patients in immune exhausted subgroup.

immunology↗

bioRxiv2020

UPRmt scales mitochondrial network expansion with protein synthesis via mitochondrial import

As organisms develop, individual cells generate mitochondria to fulfill physiologic requirements. However, it remains unknown how mitochondrial network expansion is scaled to cell growth and impacted by environmental cues. The mitochondrial unfolded protein response (UPRmt) is a signaling pathway mediated by the transcription factor ATFS-1 which harbors a mitochondrial targeting sequence (MTS)1. Here, we demonstrate that ATFS-1 mediates an adaptable mitochondrial expansion program that is active throughout normal development. Developmental mitochondrial network expansion required the relatively inefficient MTS2 in ATFS-1, which allowed the transcription factor to be responsive to parameters that impact protein import capacity of the entire mitochondrial network. Increasing the strength of the ATFS-1 MTS impaired UPRmt activity throughout development due to increased accumulation within mitochondria. The insulin-like signaling-TORC13 and AMPK pathways affected UPRmt activation4,5 in a manner that correlated with protein synthesis. Manipulation to increase protein synthesis caused UPRmt activation. Alternatively, S6 kinase inhibition had the opposite effect due to increased mitochondrial accumulation of ATFS-1. However, ATFS-1 with a dysfunctional MTS6 constitutively increased UPRmt activity independent of TORC1 function. Lastly, expression of a single protein with a strong MTS, was sufficient to expand the muscle cell mitochondrial network in an ATFS-1-dependent manner. We propose that mitochondrial network expansion during development is an emergent property of the synthesis of highly expressed mitochondrial proteins that exclude ATFS-1 from mitochondrial import, causing UPRmt activation. Mitochondrial network expansion is attenuated once ATFS-1 can be imported.

molecular biology↗

bioRxiv2020

Discovery and biosynthesis of clostyrylpyrones from the obligate an-aerobe Clostridium roseum

Anaerobic bacteria are a promising new source for natural product discovery. Examination of extracts from the obligate anaerobe Clostridium roseum led to discovery of a new family of natural products, the clostyrylpyrones. The polyketide synthase-based biosynthetic mechanism of clostyrylpyrones is further proposed based on bioinformatic, gene knockout, biochemical analysis and heterologous expression studies. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/245514v2_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@1f24265org.highwire.dtl.DTLVardef@1e51bd7org.highwire.dtl.DTLVardef@86c761org.highwire.dtl.DTLVardef@8bd052_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗