Biology subjects

He, H.

Publications and source records attributed to He, H..

At least 127 records · Page 7Linked to original sources

bioRxiv2022

Cis mutagenesis in vivo reveals extensive noncanonical functions of Dscam1 isoforms in neuronal wiring

Drosophila Dscam1 encodes ten thousand of cell recognition molecules via alternative splicing, which is required for nervous function. However, the underlying mechanism has not fully understood. Here we revealed extensive noncanonical functions of Dscam1 isoform diversity in neuronal wiring. We generated a series of allelic cis mutations in Dscam1, encoding normal number of isoforms albeit with altered isoform composition. Despite normal dendritic self-avoidance and self/non-self discrimination in da neurons, which is consistent with canonical self-avoidance model, these mutants exhibited strikingly distinct spectra of phenotypic defects in three classes of neurons: up to [~]60% defects in mushroom bodies, a significantly increased branching and growth in da neurons, and mild axonal branching defects in mechanosensory neurons. These data suggest that proper Dscam1 isoform composition is required for axon and dendrite growth in diverse neurons. This unprecedented splicing-tuned regulation unlocks new insights into the molecular mechanisms that Dscam1 isoform diversity is engaged in.

neuroscience↗

bioRxiv2022

Tomographic-encoded multiphoton (TEMP) microscopy

Axial scanning in multiphoton microscopy (MPM) is typically realized by mechanically shifting either the objective or the sample. However, the scan speed is usually hindered by the mechanical inertia of the bulky mass. Although the extended depth of field provided by the non-diffracting beam allows fast volumetric imaging, it abandons the axial resolution. Here, we demonstrate a novel and powerful tomographic technique using the Bessel droplet in MPM, termed Tomographic-Encoded MultiPhoton (TEMP) microscopy. We show that benefiting from the high-order nonlinear excitation in MPM, the side-lobes cancellation and smaller beam focus of the Bessel droplet realize better image quality. The TEMP microscopy allows fast axial scanning, less risks of photodamage and photobleaching, and high-resolution and high-contrast imaging. Furthermore, fewer raw images are required for the 3D image reconstruction. To demonstrate its usability and advantages for scattering tissues and biomedical applications, we showcase the TEMP microscopy with highly scattering fluorescence microspheres and mouse brain slice. More details can be visualized by the Bessel droplet compared with the conventional Gaussian and Bessel beam. More importantly, the TEMP technique is an easy-plug-in method for the current microscopy system. The TEMP microscopy is promising for fast volumetric multiphoton imaging, especially for highly scattering tissues.

bioengineering↗

bioRxiv2022

Physiological and molecular mechanisms regulated mesophyll conductance under severe drought in water-saving drought-resistant rice

Water-saving and drought-resistant rice (WDR) is a new type of rice varieties. It plays an important role in responding to drought with high yield and has been widely planted in central China at present. High photosynthetic production potential caused by high mesophyll conductance (gm) is the main factor promoted high yield formation in drought for WDR. But little is known about physiological and molecular mechanisms regulated gm in drought for WDR. Therefore, WDR cultivar HY73 and drought-sensitive cultivar HLY898 were used for comparative studies with three irrigation regimes before applying severe drought treatment at heading to create different differential individuals of photosynthetic potential and gm. The results showed that cultivar HY73 had lower up-regulation different expression genes (DEGs) than cultivar HLY898 in drought at transcriptional level. Conversely, DEGs of down-regulation was higher in cultivar HY73 than cultivar HLY898. In addition, 3071 DEGs were clustered in 3 modules named Midnightblue (734 DEGs), Blue (921 DEGs), and Turquoise (1416 DEGs) in severe drought merged three irrigation regimes and both cultivars, which the modules had significant correlational relationship with gm based on weighted gene co-expression network analysis (P<0.05). Only DEGs in midnightblue module were enriched in photosynthesis process and positively regulated gm (P<0.05). The main biological process were photosynthesis (GO:0015979), light harvesting in photosystem I (GO:0009768), reductive pentose-phosphate cycle (GO:0019253), protein-chromophore linkage (GO:0018298), photosynthetic electron transport in photosystem I (GO:0009773), and photosystem II repair (GO:0010206). These results indicate that gm and energy distribution in PSI and PSII systems could synergistic effect photosynthetic production potential in severe drought for rice plants. In the modules, the 18 most highly connected hub genes were screened using co-expression networks method. RT-PCR analysis indicated that CSP41B, PGLP1A, LHCA5, and GSTU6 genes had a similar variation trend with gm among treatments for both cultivar. LHCA5 and CSP41B genes were significantly up-regulated in HY73 compared with HLY898 in drought (P<0.05). And the both genes locates in thylakoid membrane in photosystems. Therefore, LHCA5 and CSP41B genes could be key genes to synergistically manage gm and energy distribution in photosystems. Our results provide some new physiological and molecular mechanisms regulated gm in severe drought for WDR.

physiology↗

bioRxiv2022

Oligomer-to-Monomer Transition Underlies the Chaperone Function of AAGAB in AP1/AP2 Assembly

Assembly of protein complexes is facilitated by assembly chaperones. Alpha and gamma adaptin binding protein (AAGAB) is a chaperone governing the assembly of the heterotetrameric adaptor complexes 1 and 2 (AP1 and AP2) involved in clathrin-mediated membrane trafficking. Here, we found that before AP1/2 binding, AAGAB exists as a homotetramer. AAGAB tetramerization is mediated by its C-terminal domain, which is critical for AAGAB stability and is missing in mutant proteins found in patients with the skin disease punctate palmoplantar keratoderma type 1 (PPKP1). We solved the crystal structure of the tetramerization domain (TD), revealing a dimer of dimer assembly. Interestingly, AAGAB uses the same TD to recognize and stabilize the {gamma} subunit in the AP1 complex and the subunit in the AP2 complex, forming binary complexes containing only one copy of AAGAB. These findings demonstrate a dual role of TD in stabilizing resting AAGAB and binding to substrates, providing a molecular explanation for disease-causing AAGAB mutations. The oligomerization state transition mechanism may also underlie the functions of other assembly chaperones.

biochemistry↗

bioRxiv2022

Spatiotemporal dissociation of brain network connectivity in salience processing: A simultaneous pupillometry-EEG-fMRI study

The processing of salient stimuli involves a wide range of both bottom-up and top-down processes. Previous neuroimaging studies have identified multiple brain areas and networks for salience processing, including the salience network (SN), dorsal attention network (DAN), and the locus coeruleus-norepinephrine (LC-NE) neuromodulatory system. However, interactions among these networks and the cortico-subcortical systems in salience processing remain unclear. Here, we simultaneously recorded pupillometry, electroencephalogram (EEG), and functional magnetic resonance imaging (fMRI) during an auditory oddball paradigm. Using EEG-informed fMRI analysis, we temporally dissociated the target stimulus evoked activation, allowing us to identify the cascades of cortical areas associated with salience processing. Furthermore, functional connectivity analysis uncovered spatiotemporal functional network organizations of these salience processing neural correlates. Using pupillometry as a psychophysiological marker of LC-NE activity, we also assessed brain-pupil relationships. With state-space modeling of target modulated effective connectivity, we found that the target evoked pupillary response is associated with the network causal couplings from late to early subsystems, as well as the network switching initiated by the SN. These findings indicate that the SN might cooperate with pupil-indexed brainstem neuromodulatory systems, such as the LC-NE system, in the reorganization and dynamic switching of cortical networks, and shed light on the implications of their integrative framework in various cognitive processes and neurological diseases.

neuroscience↗

bioRxiv2022

The Collaborative Cross strains and their founders vary widely in cocaine-induced behavioral sensitization

Cocaine use and overdose deaths attributed to cocaine have increased significantly in the United States in the last 10 years. Despite the prevalence of cocaine use disorder (CUD) and the personal and societal problems it presents, there are currently no approved pharmaceutical treatments. The absence of treatment options is due, in part, to our lack of knowledge about the etiology of CUDs. There is ample evidence that genetics plays a role in increasing CUD risk but thus far, very few risk genes have been identified in human studies. Genetic studies in mice have been extremely useful for identifying genetic loci and genes, but have been limited to very few genetic backgrounds, leaving substantial phenotypic and genetic diversity unexplored. Herein we report the measurement of cocaine-induced behavioral sensitization using a 19-day protocol that captures baseline locomotor activity, acute locomotor response to cocaine and locomotor sensitization across 5 exposures to the drug. These behaviors were measured in 51 genetically diverse yet tractable Collaborative Cross (CC) strains along with their inbred founder strains. The CC was generated by crossing 8 genetically diverse inbred strains such that each inbred CC strain has genetic contributions from each of the founder strains. Inbred CC mice are infinitely reproducible and provide a stable, yet diverse genetic platform on which to study the genetic architecture and genetic correlations among phenotypes. We have identified significant differences in cocaine locomotor sensitivity and behavioral sensitization across the panel of CC strains and their founders. We have established relationships among cocaine sensitization behaviors and identified extreme responding strains that can be used in future studies aimed at understanding the genetic, biological and pharmacological mechanisms that drive addiction-related behaviors. Finally, we have determined that these behaviors exhibit relatively robust heritability making them amenable to future genetic mapping studies to identify addiction risk genes and genetic pathways that can be studied as potential targets for the development of novel therapeutics.

genetics↗

bioRxiv2022

Reversal Learning Phenotypes are Linked with Novel Genetic Loci in Diversity Outbred Mice

Impulsive behavior and impulsivity are heritable phenotypes that are strongly associated with risk for substance use disorders in human subjects. Consequently, identifying the neurogenetic mechanisms that influence impulsivity may also reveal novel biological insights into addiction vulnerability. Past studies from our laboratory using the BXD and Collaborative Cross (CC) recombinant inbred mouse panels have revealed that behavioral indicators of impulsivity measured in a reversal learning task are heritable and are genetically correlated with aspects of intravenous cocaine self-administration. Genome wide linkage studies in the BXD panel revealed a quantitative trait locus (QTL) on chromosome 10, but the specific genes affecting this trait remain elusive. To achieve greater precision in our mapping efforts, we have turned to Diversity Outbred (DO) mice. A total of 392 DO mice (230 males, 295 females) were successfully phenotyped using the same reversal learning test utilized in our earlier studies. Our primary indicator of impulsive responding, a measure that isolates the relative difficulty mice have with reaching performance criteria under reversal conditions, revealed a genome wide significant QTL on chromosome 7 (max LOD score = 8.73, p<0.05). A measure of premature responding akin to that implemented in the 5-choice serial reaction time task yielded a suggestive QTL on chromosome 17 (max LOD score = 9.14, p<0.1). Positional candidate genes were prioritized (2900076A07Rik, Wdr73 and Zscan2) based upon expression QTL data we collected in DO and CC mice and analyses using publicly available gene expression and phenotype databases. These findings may advance understanding of the genetics that drive impulsive behavior and enhance risk for substance use disorders.

genetics↗

bioRxiv2022

Genomic and phylogenetic analysis of the first myovirus isolated from Oceanospirillaceae, representing a novel viral cluster prevalent in polar oceans

The marine bacterial family Oceanospirillaceae, which is abundant in the deep-seas and polar oceans, is closely associated with algal blooms and petroleum hydrocarbons degradation. However, only a few Oceanospirillaceae-infecting phages have so far been reported. Here we report on a novel Oceanospirillum phage, vB_OsaM_PD0307, which is the first myovirus to be found that infects Oceanospirillaceae. vB_OsaM_PD0307 with a 44,421 bp linear dsDNA genome. Phylogenetic analysis and average nucleotide sequence identities suggest that vB_OsaM_PD0307 is different from other phage isolates and represents a novel genus-level myoviral cluster with two high-quality uncultured viral genomes, designed as Oceanospimyovirus. Additionally, the biogeographical distribution of the vB_OsaM_PD0307 cluster suggests that they are widespread in the oceans and abundant in polar areas. In summary, our findings expand the current understanding of the phylogenetic diversity, genomic characteristic and function of Oceanospimyovirus phages, and highlight the role of the vB_OsaM_PD0307 phage as a major ecological agent that can infect certain key bacterial groups associated with polar algal blooms. ImportanceOceanospirillumphage vB_OsaM_PD0307 is the first myovirus found to infect Oceanospirillaceae and represents a novel viral genus, Oceanospimyovirus. This study provides insights into the genomic, phylogenetic, and ecological characteristics of myoviruses infecting Oceanospirillaceae and improves our understanding of the interactions between Oceanospirillaceae and their phages in the oceans.

genomics↗

bioRxiv2022

Harringtonine has the effects of double blocking SARS-CoV-2 membrane fusion

Fusion with host cell membrane is the main mechanism of infection of SARS-CoV-2. Here, we propose a new strategy to double block SARS-CoV-2 membrane fusion by using Harringtonine (HT), a small-molecule antagonist. By using cell membrane chromatography (CMC), we found that HT specifically targeted the SARS-CoV-2 S protein and host cell TMPRSS2, and then confirmed that HT can inhibit pseudotyped virus membrane fusion. Furthermore, HT successfully blocked SARS-CoV-2 infection, especially in the delta and Omicron mutant. Since HT is a small-molecule antagonist, it is minimally affected by the continuous variation of SARS-CoV-2. Our findings show that HT is a potential small-molecule antagonist with a new mechanism of action against SARS-CoV-2 infection, and thus HT mainly targets the S protein, and thus, greatly reduces the damage of the S proteins autotoxicity to the organ system, has promising advantages in the clinical treatment of COVID-19.

pharmacology and toxicology↗

bioRxiv2021

Potential inhibitors for blocking the interaction of the coronavirus SARS-CoV-2 spike protein and its host cell receptor ACE2

The outbreak of SARS-CoV-2 continues to pose a serious threat to human health and social and economic stability. In this study, we established an anti-coronavirus drug screening platform based on the Homogeneous Time Resolved Fluorescence (HTRF) technology and the interaction between the coronavirus S protein and its host receptor ACE2. This platform is a rapid, sensitive, specific, and high throughput system. With this platform, we screened two compound libraries of 2,864 molecules and identified three potential anti-coronavirus compounds: tannic acid (TA), TS-1276 (anthraquinone), and TS-984 (9-Methoxycanthin-6-one). Our in vitro validation experiments indicated that TS-984 strongly inhibits the interaction of the coronavirus S-protein and the human cell ACE2 receptor. This data suggests that TS-984 is a potent blocker of the interaction between the S-protein and ACE2, which might have the potential to be developed into an effective anti-coronavirus drug. SIGNIFICANCEThe ongoing pandemic of COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made a serious threat to public health worldwide. Given the urgency of the situation, researchers are attempting to repurpose existing drugs for treating COVID-19. In this present study, we screened two compound libraries of 2,864 molecules and identified a potent inhibitor (TS-984) for blocking the coronavirus S-protein and the human cell ACE2 receptor. TS-984 might have the potential to be developed into an effective anti-coronavirus drug for treating COVID-19.

pharmacology and toxicology↗

bioRxiv2021

A deep learning-based multisite neuroimage harmonization framework established with traveling-subject dataset

The accumulation of multisite large-sample MRI datasets collected by large brain research projects in the last decade has provided a critical resource for understanding the neurobiological mechanisms underlying cognitive functions and brain disorders. However, the significant site effects, observed in the imaging data and their derived structural and functional features, has prevented the derivation of consistent findings across different studies. The development of harmonization methods that can effectively eliminate complex site effects while maintaining biological characteristics in neuroimaging data has become a vital and urgent requirement for multisite imaging studies. Here, we proposed a deep learning-based framework to harmonize imaging data from pairs of sites, in which site factors and brain features can be disentangled and encoded. We trained the proposed framework with a publicly available traveling-subject dataset from SRPBS and harmonized the gray matter volume maps from eight source sites to a target site. The proposed framework significantly eliminated inter-site differences in gray matter volume. The embedded encoders successfully captured both the abstract texture of site factors and the concrete brain features. Moreover, the proposed framework exhibited outstanding performance relative to conventional statistical harmonization methods in site effect removal, data distribution homogenization, and intra-subject similarity improvement. Together, the proposed method offers a powerful and interpretable deep learning-based harmonization framework for multisite neuroimaging data that could enhance reliability and reproducibility in multisite studies for brain development and brain disorders.

neuroscience↗

bioRxiv2021

Post-translational modification patterns on β-myosin heavy chain are altered in ischemic and non-ischemic human hearts

Phosphorylation and acetylation of sarcomeric proteins are important for fine-tuning myocardial contractility. Here, we used bottom-up proteomics and label-free quantification to identify novel post-translational modifications (PTMs) on beta-myosin heavy chain ({beta}-MHC) in normal and failing human heart tissues. We report six acetylated lysines and two phosphorylated residues: K34-Ac, K58-Ac, S210-P, K213-Ac, T215-P, K429-Ac, K951-Ac, and K1195-Ac. K951-Ac was significantly reduced in both ischemic and non-ischemic failing hearts compared to non-diseased hearts. Molecular dynamics simulations show that K951-Ac may impact stability of thick filament tail interactions and ultimately myosin head positioning. K58-Ac altered the solvent exposed SH3 domain surface - known for protein-protein interactions - but did not appreciably change motor domain conformation or dynamics under conditions studied. Together, K213-Ac/T215-P altered loop 1s structure and dynamics - known to regulate ADP-release, ATPase activity, and sliding velocity. Our study suggests that {beta}-MHC acetylation levels may be influenced more by the PTM location than the type of heart disease since less protected acetylation sites are reduced in both heart failure groups. Additionally, these PTMs have potential to modulate interactions between {beta}-MHC and other regulatory sarcomeric proteins, ADP-release rate of myosin, flexibility of the S2 region, and cardiac myofilament contractility in normal and heart failure hearts.

physiology↗

bioRxiv2021

Total virome characterizations of game animals in China reveals a spectrum of emerging viral pathogens

Game animals are wildlife species often traded and consumed as exotic food, and are potential reservoirs for SARS-CoV and SARS-CoV-2. We performed a meta-transcriptomic analysis of 1725 game animals, representing 16 species and five mammalian orders, sampled across China. From this we identified 71 mammalian viruses, with 45 described for the first time. Eighteen viruses were considered as potentially high risk to humans and domestic animals. Civets (Paguma larvata) carried the highest number of potentially high risk viruses. We identified the transmission of Bat coronavirus HKU8 from a bat to a civet, as well as cross-species jumps of coronaviruses from bats to hedgehogs and from birds to porcupines. We similarly identified avian Influenza A virus H9N2 in civets and Asian badgers, with the latter displaying respiratory symptoms, as well as cases of likely human-to-wildlife virus transmission. These data highlight the importance of game animals as potential drivers of disease emergence. HighlightsO_LI1725 game animals from five mammalian orders were surveyed for viruses C_LIO_LI71 mammalian viruses were discovered, 18 with a potential risk to humans C_LIO_LICivets harbored the highest number of potential high risk viruses C_LIO_LIA species jump of an alphacoronavirus from bats to a civet was identified C_LIO_LIH9N2 influenza virus was detected in a civet and an Asian badger C_LIO_LIHumans viruses were also identified in game animals C_LI

zoology↗

bioRxiv2021

BRCA1 and ELK-1 regulate Neural Progenitor Cell Fate in the Optic Tectum in response toVisual Experience in Xenopus laevis tadpoles

In developing Xenopus tadpoles, the optic tectum begins to receive patterned visual input while visuomotor circuits are still undergoing neurogenesis and circuit assembly. This visual input regulates neural progenitor cell fate decisions such that maintaining tadpoles in the dark increases proliferation, expanding the progenitor pool, while visual stimulation promotes neuronal differentiation. To identify regulators of activity-dependent neural progenitor cell fate, we used RNA-Seq to profile the transcriptomes of proliferating neural progenitor cells and newly-differentiated immature neurons. Out of 1,130 differentially expressed (DE) transcripts, we identified six DE transcription factors which are predicted to regulate the majority of the other DE transcripts. Here we focused on Breast cancer 1 (BRCA1) and the ETS-family transcription factor, ELK-1. BRCA1 is known for its role in cancers, but relatively little is known about its potential role in regulating neural progenitor cell fate. ELK-1 is a multifunctional transcription factor which regulates immediate early gene expression. We investigated the effect of BRCA1 and ELK-1 on activity-regulated neurogenesis in the tadpole visual system using in vivo time-lapse imaging to monitor the fate of turbo-GFP-expressing SOX2+ neural progenitor cells in the optic tectum. Our longitudinal in vivo imaging analysis shows that knockdown of either BRCA1 or ELK-1 altered the fates of neural progenitor cells, and furthermore that the effects of visual experience on neurogenesis depend on BRCA1 expression, while the effects of visual experience on neuronal differentiation depend on ELK-1 expression. These studies provide insight into the potential mechanisms by which neural activity affects neural progenitor cell fate.

neuroscience↗

bioRxiv2021

Fast Optoacoustic Mesoscopy of Microvascular Endothelial Dysfunction in Cardiovascular Risk and Disease

Microvascular endothelial dysfunction (ED) precedes the ED in larger arteries and is an early marker of cardiovascular disease (CVD). While precise assessment of microvascular ED could thus be used for the early detection and risk stratification of CVD, detailed interrogation of skin microvascular ED is limited by the technology available. Herein, we applied a novel approach for the non-invasive assessment of skin microvascular ED by developing fast plane raster-scan optoacoustic mesoscopy (FP-RSOM) to visualize and quantify skin microvasculature perfusion changes during post-occlusive hyperemia (PORH) tests. We combined static three-dimensional RSOM imaging with fast dynamic FP-RSOM measurements (1 frame / second) in human skin in vivo, which allowed for the first time to fully visualize the cutaneous microvascular response and further quantify changes of individual vessel diameter, total blood volume and vessel density during the PORH process. We further computed biomarkers from FP-RSOM images to quantify skin endothelial function within different skin layers as a function of skin depth, while conventional approaches mainly measure overall changes within sampled tissue volumes. FP-RSOM applied on smokers and patients with CVD showed clear ED in both groups compared to healthy volunteers. Moreover, FP-RSOM imaging showed higher sensitivity in quantifying the effects of smoking and CVD on skin microvascular endothelial function compared to clinically used laser Doppler flowmetry and tissue spectrometry (O2C). Our study introduces FP-RSOM as a novel tool to visualize and quantify skin microvascular ED as an early marker for the diagnostics and monitoring of cardiovascular risk and disease.

bioengineering↗

bioRxiv2021

On the origin and evolution of Drosophila new genes during spermatogenesis

Origin of functional new genes is a basic biological process that has significant contribution to organismal diversity. Previous studies in both Drosophila and mammals showed that new genes tend to be expressed in testis, and avoid the X chromosome presumably because meiotic sex chromosome inactivation (MSCI). Here we analyze the published single-cell transcriptome data of Drosophila adult testis and find an enrichment of male germline mitotic genes, but an underrepresentation of meiotic genes on the X chromosome. This can be attributed to an excess of autosomal meiotic genes that were derived from their X-linked mitotic progenitors, which provides direct cell-level evidence for MSCI in Drosophila. We reveal that new genes, particularly those produced by retrotransposition, tend to exhibit an expression shift toward late spermatogenesis compared to their parental copies, probably due to the more intensive sperm competition or sexual conflict. Our results dissect the complex factors including the age, the origination mechanisms and the chromosomal locations that influence the new gene origination and evolution in testis, and identify new gene cases that show divergent cell-level expression pattern from their progenitors for future functional studies.

evolutionary biology↗

bioRxiv2021

Autophagosomes fuse to phagosomes and play important roles in the degradation of apoptotic cells in Caenorhabditis elegans

Autophagosomes are double-membrane intracellular vesicles that degrade protein aggregates, intracellular organelles, and other cellular components. During the development of the nematode Caenorhabditis elegans, many somatic and germ cells undergo apoptosis. These cells are engulfed and degraded by their neighboring cells. We discovered a novel role of autophagosomes in facilitating the degradation of apoptotic cells using a real-time imaging technique. Specifically, the double-membrane autophagosomes in engulfing cells are recruited to the surfaces of phagosomes containing apoptotic cells and subsequently fuse to phagosomes, allowing the inner vesicle to enter the phagosomal lumen. Mutants defective in the production of autophagosomes display significant defects in the degradation of apoptotic cells, demonstrating the importance of autophagosomes to this process. The signaling pathway led by the phagocytic receptor CED-1, the adaptor protein CED-6, and the large GTPase dynamin (DYN-1) promotes the recruitment of autophagosomes to phagosomes. Moreover, the subsequent fusion of autophagosomes with phagosomes requires the functions of the small GTPase RAB-7 and the HOPS complex components. Further observations suggest that autophagosomes provide apoptotic cell-degradation activities in addition to and in parallel of lysosomes. Our findings reveal that, unlike the single-membrane, LC3-associated phagocytosis (LAP) vesicles reported for mammalian phagocytes, the canonical double-membrane autophagosomes facilitate the clearance of C. elegans apoptotic cells. These findings add autophagosomes to the collection of intracellular organelles that contribute to phagosome maturation, identify novel crosstalk between the autophagy and phagosome maturation pathways, and discover the upstream signaling molecules that initiate this crosstalk.

cell biology↗

bioRxiv2021

Isolation and characterizations of a novel H6N1 avian influenza virus from Von Schrenck's Bittern (Ixobrychus eurhythmus) in Jiangxi province, China

In June 2013, the first case of human infection with an avian H6N1 virus was reported in a Taiwanese woman. Although this was a single non-fatal case, the virus continues to circulate in Taiwanese poultry. As with any emerging avian virus that infects humans, there is concern that acquisition of human-type receptor specificity could enable transmission in the human population. Despite mutations in the receptor-binding pocket of the human H6N1 isolate, it has retained avian-type (NeuAca2-3Gal) receptor specificity. An H6N1 AIV was isolated from a Von Schrencks Bittern during national active surveillance project for avian influenza viruses (AIVs) in wild birds in Jiangxi province, China 2018. Phylogenetic analysis showed that this strain received its genes from H1, H2, H3, H4, H6 and H10 AIVs in different places. This strain was found to be minimally pathogenic in mice and was able to replicate in mice without prior adaptation. Considering that the reassorted H6N1 virus was isolated from Von Schrencks Bittern in this study, it is possible that this bird can play an important role in the generation of novel reassorted H6 AIVs. In this study, H6N1 virus is a wild virus migration brought from different regions of the AIV gene into the natural gene pool, resulting in the production of a recombinant new virus. The H6N1 virus can be seen as a link in the evolution of the virus and the evolution of other viruses.

molecular biology↗