bioRxiv Science⌕ Search

Biology subjects

Jin, J.

Publications and source records attributed to Jin, J..

At least 127 records · Page 7Linked to original sources

WDR5 promotes breast cancer growth and metastasis via KMT2-independent translation regulation

Metastatic breast cancer remains a major cause of cancer related deaths in women and there are few effective therapies against this advanced disease. Emerging evidence suggests that key steps of tumor progression and metastasis are controlled by reversible epigenetic mechanisms. Using an in vivo genetic screen, we identified WDR5 as an actionable epigenetic regulator that is required for metastatic progression in models of triple-negative breast cancer. We found that knockdown of WDR5 in breast cancer cells independently impaired their tumorigenic as well as metastatic capabilities. Mechanistically, WDR5 promotes cell growth by increasing ribosomal gene expression and translation efficiency in a KMT2-independent manner. Consistently, pharmacological inhibition or degradation of WDR5 impedes cellular translation rate and the clonogenic ability of breast cancer cells. Furthermore, combination of WDR5-targeting with mTOR inhibitors leads to potent suppression of translation and proliferation of breast cancer cells. These results reveal novel therapeutic strategies to treat metastatic breast cancer.

cancer biology↗

Novel Methods for Multi-ancestry Polygenic Prediction and their Evaluations in 3.7 Million Individuals of Diverse Ancestry

Polygenic risk scores (PRS) increasingly predict complex traits, however, suboptimal performance in non-European populations raise concerns about clinical applications and health inequities. We developed CT-SLEB, a powerful and scalable method to calculate PRS using ancestry-specific GWAS summary statistics from multi-ancestry training samples, integrating clumping and thresholding, empirical Bayes and super learning. We evaluate CT-SLEB and nine-alternatives methods with large-scale simulated GWAS ([~]19 million common variants) and datasets from 23andMe Inc., the Global Lipids Genetics Consortium, All of Us and UK Biobank involving 5.1 million individuals of diverse ancestry, with 1.18 million individuals from four non-European populations across thirteen complex traits. Results demonstrate that CT-SLEB significantly improves PRS performance in non-European populations compared to simple alternatives, with comparable or superior performance to a recent, computationally intensive method. Moreover, our simulation studies offer insights into sample size requirements and SNP density effects on multi-ancestry risk prediction.

genetics↗

Topologically engineered antibodies and Fc-fusion proteins: a new class of multifunctional therapeutic candidates for SARS-CoV-2, cancer, and other disease

Traditional Y-shaped IgG topologies restrict conventional multispecific antibodies by imposing steric constraints that hinder target binding and stability. To overcome this, we engineered tetrahedral antibodies, a multispecific class that non-covalently self-assembles via two hinge-integrated collectrin-like domains (CLDs). This non-planar, tetrapartite architecture coordinates up to six unobstructed Fab, Fc, and extracellular domains. Parallel to the clinical translation of our dual-Fc anti-CD19/CD20 tetrahedral antibody for systemic lupus erythematosus (SLE), we evaluated an anti-SARS-CoV-2 candidate that exhibited in vivo efficacy in non-human primates. Furthermore, we demonstrate functional Fc{gamma}R binding cooperativity across the dual-Fc domains of anti-CD19/CD20 tetrahedral antibodies, while introducing an interface disulfide bond into the CLD dimer increases structural stability as evidenced by effectively abolishing CLD dynamic dissociation and resolving the dissociation equilibrium into discrete, stable quaternary states. These findings establish tetrahedral architectures as a robust, translatable multispecific platform.

molecular biology↗

Numb-associated kinases are required for SARS-CoV-2 infection and are cellular targets for therapy

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose serious threats to global health. We previously reported that AAK1, BIKE and GAK, members of the Numb-associated kinase family, control intracellular trafficking of multiple RNA viruses during viral entry and assembly/egress. Here, using both genetic and pharmacological approaches, we probe the functional relevance of NAKs for SARS-CoV-2 infection. siRNA-mediated depletion of AAK1, BIKE, GAK, and STK16, the fourth member of the NAK family, suppressed SARS-CoV-2 infection in human lung epithelial cells. Both known and novel small molecules with potent AAK1/BIKE, GAK or STK16 activity suppressed SARS-CoV-2 infection. Moreover, combination treatment with the approved anti-cancer drugs, sunitinib and erlotinib, with potent anti-AAK1/BIKE and GAK activity, respectively, demonstrated synergistic effect against SARS-CoV-2 infection in vitro. Time-of-addition experiments revealed that pharmacological inhibition of AAK1 and BIKE suppressed viral entry as well as late stages of the SARS-CoV-2 life cycle. Lastly, suppression of NAKs expression by siRNAs inhibited entry of both wild type and SARS-CoV-2 pseudovirus. These findings provide insight into the roles of NAKs in SARS-CoV-2 infection and establish a proof-of-principle that pharmacological inhibition of NAKs can be potentially used as a host-targeted approach to treat SARS-CoV-2 with potential implications to other coronaviruses.

microbiology↗

Human Galectin-9 Potently Enhances SARS-CoV-2 Replication and Inflammation in Airway Epithelial Cells

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has caused a global economic and health crisis. Recently, plasma levels of galectin-9 (Gal-9), a {beta}-galactoside-binding lectin involved in immune regulation and viral immunopathogenesis, were reported to be elevated in the setting of severe COVID-19 disease. However, the impact of Gal-9 on SARS-CoV-2 infection and immunopathology remained to be elucidated. Here, we demonstrate that Gal-9 treatment potently enhances SARS-CoV-2 replication in human airway epithelial cells (AECs), including primary AECs in air-liquid interface (ALI) culture. Gal-9-glycan interactions promote SARS-CoV-2 attachment and entry into AECs in an ACE2-dependent manner, enhancing the binding affinity of the viral spike protein to ACE2. Transcriptomic analysis revealed that Gal-9 and SARS-CoV-2 infection synergistically induce the expression of key pro-inflammatory programs in AECs including the IL-6, IL-8, IL-17, EIF2, and TNF signaling pathways. Our findings suggest that manipulation of Gal-9 should be explored as a therapeutic strategy for SARS-CoV-2 infection. ImportanceCOVID-19 continues to have a major global health and economic impact. Identifying host molecular determinants that modulate SARS-CoV-2 infectivity and pathology is a key step in discovering novel therapeutic approaches for COVID-19. Several recent studies have revealed that plasma concentrations of the human {beta}-galactoside-binding protein galectin-9 (Gal-9) are highly elevated in COVID-19 patients. In this study, we investigated the impact of Gal-9 on SARS-CoV-2 pathogenesis ex vivo in airway epithelial cells (AECs), the critical initial targets of SARS-CoV-2 infection. Our findings reveal that Gal-9 potently enhances SARS-CoV-2 replication in AECs, interacting with glycans to enhance the binding between viral particles and entry receptors on the target cell surface. Moreover, we determined that Gal-9 accelerates and exacerbates several virus-induced pro-inflammatory programs in AECs that are established signature characteristics of COVID-19 disease and SARS-CoV-2-induced acute respiratory distress syndrome (ARDS). Our findings suggest that Gal-9 is a promising pharmacological target for COVID-19 therapies.

microbiology↗

Does ankle push-off correct for errors in anterior-posterior foot placement relative to center-of-mass state?

I.Understanding the mechanisms humans use to stabilize walking is vital for predicting falls in elderly. Modeling studies identified two potential mechanisms to stabilize gait in the anterior-posterior direction: foot placement control and ankle push-off control: Foot placement depends on position and velocity of the center-of-mass (CoM) and push-off modulates with deviations between actual and predicted CoM trajectories. While both control mechanisms have been reported in humans, it is unknown whether especially the latter one is employed in unperturbed steady-state walking. On the one hand, the covariance between CoM states and anterior-posterior foot placement served as a measure of foot placement control. On the other hand, we determined variations in ankle push-off as a function of differences between the actual foot placement and the one predicted from CoM states. We estimated the corresponding correlations and consider them indictors for push-off control based on foot placement errors. We found ankle push-off torque to be correlated to the foot placement error in 30 participants when walking at normal and slow speed, with mean correlation values of up to 0.45. Our study suggests that humans use a push-off strategy for correcting foot placement errors in steady-state walking.

physiology↗

Scale Bar of Aging Trajectories for Screening Personal Rejuvenation Treatments

Although aging is an increasingly severe healthy, economic, and social global problem, it is far from well-modeling aging due to the aging processs complexity. To promote the aging modeling, here we did the quantitative measurement based on aging blood transcriptome. Specifically, the aging blood transcriptome landscape was constructed through ensemble modeling in a cohort of 505 people, and 1138 age-related genes were identified. To assess the aging rate in the linear dimension of aging, we constructed a simplified linear aging clock, which distinguished fast-aging and slow-aging populations and showed the differences in the composition of immune cells. Meanwhile, the non-linear dimension of aging revealed the transcriptome fluctuations with a crest around the age of 40 and showed that this crest came earlier and was more vigorous in the fast-aging population. Moreover, the aging clock was applied to evaluate the rejuvenation effect of molecules in vitro, such as Nicotinamide Mononucleotide (NMN) and Metformin. In sum, this study developed a de novo aging clock to evaluate agedependent precise medicine by revealing its fluctuation nature based on comprehensively mining the aging blood transcriptome, promoting the development of personal aging monitoring and anti-aging therapies.

bioengineering↗

A theory of cortical map formation in the visual brain

The cerebral cortex receives multiple afferents from the thalamus that segregate by stimulus modality forming cortical maps for each sense. In vision, the primary visual cortex maps the multiple dimensions of the visual stimulus in patterns that vary across species for reasons unknown. Here we introduce a general theory of cortical map formation, which proposes that map diversity emerges from species variations in the thalamic afferent density sampling sensory space. In the theory, increasing afferent sampling density enlarges the cortical domains representing the same visual point, allowing the segregation of afferents and cortical targets by multiple stimulus dimensions. We illustrate the theory with an afferent-density model that accurately replicates the maps of different species through afferent segregation followed by thalamocortical convergence pruned by visual experience. Because thalamocortical pathways use similar mechanisms for axon segregation and pruning, the theory may extend to other sensory areas of the mammalian brain.

neuroscience↗

MDR1 Drug Efflux Pump Promotes Intrinsic and Acquired Resistance to PROTACs in Cancer Cells

PROTACs (Proteolysis-Targeting Chimeras) represent a promising new class of drugs that selectively degrade proteins of interest from cells. PROTACs targeting oncogenes are avidly being explored for cancer therapies, with several currently in clinical trials. Drug resistance represents a significant challenge in cancer therapies, and the mechanism by which cancer cells acquire resistance to PROTACs remains poorly understood. Using proteomics, we discovered acquired and intrinsic resistance to PROTACs in cancer cells can be mediated by upregulation of the drug efflux pump MDR1. PROTAC-resistant cells could be re-sensitized to PROTACs through co-administering MDR1 inhibitors. Notably, co-treatment of MDR1-overexpressing colorectal cancer cells with MEK1/2 or KRASG12C degraders and the dual ErbB receptor/MDR1 inhibitor lapatinib exhibited potent drug synergy due to simultaneous blockade of MDR1 and ErbB receptor activity. Together, our findings suggest that concurrent blockade of MDR1 will likely be required in combination with PROTACs to achieve durable protein degradation and therapeutic response in cancer.

cancer biology↗

Reversible brain edema in experimental cerebral malaria is associated with transcellular blood-brain barrier disruption and delayed microhemorrhages

Brain swelling occurs in cerebral malaria (CM) and may either reverse or result in fatal outcome. It is currently unknown how brain swelling in CM reverses, as investigations have been hampered by inadequate animal models. In this study, we show that reversible brain swelling in experimental murine cerebral malaria (ECM) can be induced reliably after single vaccination with radiation-attenuated sporozoites as revealed by in vivo high-field (9.4T) magnetic resonance imaging. Our results provide evidence that parenchymal fluid increase and consecutive brain swelling results from transcellular blood-brain barrier disruption (BBBD), as revealed by electron microscopy. This mechanism enables reversal of brain swelling but does not prevent persistent focal brain damage, evidenced by microhemorrhages, in areas of most severe BBBD. In a cohort of 27 pediatric and adult CM patients (n=4 fatal, n=23 non-fatal) two out of four fatal CM patients (50%) and 8 out of 23 non-fatal CM patients (35%) showed microhemorrhages on MRI at clinical field strength of 1.5T, emphasizing the translational potential of the experimental model. Our data suggest that targeting transcellular BBBD may represent a promising adjunct therapeutic approach in cerebral brain swelling to reduce edema and may ultimately lead to a reduced permanent brain damage and a better longtime neurological outcome. Author summaryBrain swelling, which occurs in diseases such as cerebral malaria, is not necessarily fatal, and may reverse. Even upon reversal of brain swelling, neurological sequelae can still occur. The factors contributing to the reversibility of brain edema are not known, and treatment options remain therefore limited. Identifying the mechanisms leading to such reversibility could inform clinical management aimed at decreasing brain swelling and consecutive brain injury. Here we introduce a reproducible and simple animal model that allows comprehensive in vivo studies of reversible brain swelling in cerebral malaria at the peak of disease and upon recovery. We identify a specific type of blood-brain barrier disruption (BBBD) as a mechanism that occurs in brain swelling. We show that BBBD can reverse, but also highlight remaining brain damage in areas of most severe BBBD. As the ECM model introduced here bares crucial similarities to the CM in humans, our findings open strategies to study new therapeutic avenues and point to compounds that specifically target transcellular BBBD to reduce brain edema, and increase survival rates.

neuroscience↗

Eliminating fibroblast activation protein-α expressing cells by photoimmunotheranostics

Photoimmunotherapy (PIT) using an antibody conjugated to a near infrared dye IR700 is achieving significant success in target-specific elimination of cells. Fibroblast activation protein alpha (FAP-) is an important target in cancer because of its expression by cancer associated fibroblasts (CAFs) as well as by some cancer cells. CAFs that express FAP- have protumorigenic and immune suppressive functions. Using immunohistochemistry of human breast cancer tissue microarrays, we identified an increase of FAP-+ CAFs in invasive breast cancer tissue compared to adjacent normal tissue. We found FAP- expression increased in fibroblasts co-cultured with cancer cells. In proof-of-principle studies, we engineered human FAP- overexpressing MDA-MB-231 and HT-1080 cancer cells and murine FAP- overexpressing NIH-3T3 fibroblasts to evaluate several anti-FAP- antibodies and selected AF3715 based on its high binding-affinity with both human and mouse FAP-. After conjugation of AF3715 with the phthalocyanine dye IR700, the resultant antibody conjugate, FAP--IR700, was evaluated in cells and tumors for its specificity and effectiveness in eliminating FAP- expressing cell populations with PIT. FAP--IR700-PIT resulted in effective FAP--specific cell killing in the engineered cancer cells and in two patient-derived CAFs in a dose-dependent manner. Following an intravenous injection, FAP--IR700 retention was three-fold higher than IgG-IR700 in FAP- overexpressing tumors, and two-fold higher compared to wild-type tumors. FAP--IR700-PIT resulted in significant growth inhibition of tumors derived from FAP- overexpressing human cancer cells. A reduction of endogenous FAP-+ murine CAFs was identified at 7 days after FAP--IR700-PIT. FAP--targeted NIR-PIT presents a promising strategy to eliminate FAP-+ CAFs.

cancer biology↗

In situ Alphavirus Assembly and Budding Mechanism Revealed by Cellular CryoET

Chikungunya virus (CHIKV) is an alphavirus and the etiological agent for debilitating arthritogenic disease in humans. Previous studies with purified virions or budding mutants have not resolved the structural mechanism of alphavirus assembly in situ. Here we used cryogenic electron tomography (cryoET) imaging of CHIKV-infected human cells and subvolume classification to resolve distinct assembly intermediate conformations. These structures revealed that particle formation is driven by the spike envelope layer. Additionally, we showed that asymmetric immature nucleocapsids (NCs) provide scaffolds to trigger assembly of the icosahedral spike lattice, which progressively transforms immature NCs into icosahedral cores during virus budding. Further, cryoET of the infected cells treated with neutralizing antibodies (NAbs) showed that NAb-induced blockage of CHIKV assembly was achieved by preventing spike-spike lateral interactions that are required to bend the plasma membrane around NC cores. These findings provide molecular mechanisms for designing antivirals targeting spike-driven assembly/budding of viruses.

microbiology↗

Molecular and cellular adaptations in hippocampal parvalbumin neurons mediate behavioral responses to chronic social stress

Parvalbumin-expressing interneurons (PV neurons) maintain inhibitory control of local circuits implicated in behavioral responses to environmental stressors. However, the roles of molecular and cellular adaptations in PV neurons in stress susceptibility or resilience have not been clearly established. Here, we show behavioral outcomes of chronic social defeat stress (CSDS) are mediated by differential neuronal activity and gene expression in hippocampal PV neurons in mice. Using in vivo electrophysiology and chemogenetics, we find increased PV neuronal activity in the ventral dentate gyrus is required and sufficient for behavioral susceptibility to CSDS. PV neuron-selective translational profiling indicates mitochondrial oxidative phosphorylation is the most significantly altered pathway in stress-susceptible versus resilient mice. Among differentially expressed genes associated with stress-susceptibility and resilience, we find Ahnak, an endogenous regulator of L-type calcium channels which are implicated in the regulation of mitochondrial function and gene expression. Notably, Ahnak deletion in PV neurons impedes behavioral susceptibility to CSDS. Altogether, these findings indicate behavioral effects of chronic stress can be controlled by selective modulation of PV neuronal activity or a regulator of L-type calcium signaling in PV neurons.

neuroscience↗

Conservation and divergence of poly(A) tail regulation during the mammalian oocyte-to-embryo transition

Poly(A) tail length and non-A residues are vital for oocyte-to-embryo transition (OET) in mice and humans1-5. However, the role of poly(A) tail length and non-A residues during OET in other commonly used mammalian animal models for human diseases remains unexplored. In addition, the degree of conservation in maternal mRNA poly(A) tail dynamics during OET across different mammal species is unknown. Here, we conduct a comparative analysis of the poly(A) tails during OET across four species: mice, rats, pigs, and humans. Dynamics during OET found to be conserved across all four species include: maternal mRNA deadenylation during oocyte maturation and re-polyadenylation after fertilization; a fall-rise trend in poly(A) tail length distribution; a rise-fall trend in the ratio of poly(A) tails with non-A residues; higher abundance of non-A residues in poly(A) tails of maternal mRNA than in zygotic genome activation (ZGA) mRNA; maternal mRNA with U residues degrades faster than those without U residues at the stage when ZGA takes place. While in mice and rats maternal mRNA deadenylation is impaired in parthenogenetic embryos and ZGA inhibition leads to blocked maternal mRNA deadenylation in mice and humans. In contrast, the length of consecutive U residues and the duration time of U residues in poly(A) tail diverges across the four species. Together, these findings reveal that the poly(A) tail mediated maternal mRNA post-transcriptional regulation is highly conserved in mammals with unique divergences in the length and life-span of U residues, providing new insights for the further understanding of OET across different mammals.

developmental biology↗

The STAT5-IRF4-BATF pathway drives heightened epigenetic remodeling in naïve CD4+ T cell responses of older adults

T cell aging is a complex process combining the emergence of cellular defects with activation of adaptive mechanisms. Generation of T cell memory is impaired, while a low-inflammatory state is induced, in part due to effector T cells. To determine whether age-associated changes in T cell fate decisions occur early after T cell activation, we profiled the longitudinal transcriptional and epigenetic landscape induced by TCR stimulation comparing naive CD4+ T cells from young and older adults. In spite of attenuated TCR signaling, activation-induced remodeling of the epigenome increased with age, culminating in heightened BATF and BLIMP1 activity. Single cell studies, integrating ATAC-seq and RNA-seq data, identified increases in dysfunctional and in effector T cells and a decrease in BACH2-expressing memory cell precursors. STAT5 activation, in part due to a decline in HELIOS and aberrant IL-2 receptor expression, accounted for the induction of transcription factor networks favoring effector cell differentiation.

immunology↗

Directed yeast genome evolution by controlled introduction of trans-chromosomic structural variations

Naturally occurring structural variations (SVs) are a considerable source of genomic variation and can reshape chromosomes 3D architecture. The synthetic chromosome rearrangement and modification by loxP-mediated evolution (SCRaMbLE) system has been proved to generate random SVs to impact phenotypes and thus constitutes powerful drivers of directed genome evolution. However, how to reveal the molecular mechanism insights into the interactions between phenotypes and complex SVs, especially inversions and translocations, has so far remained challenging. In this study, we develop a SV-prone yeast strain by using SCRaMbLE with two synthetic chromosomes, synV and synX. An heterologous biosynthesis pathway allowing a high throughput screen for increased yield of astaxanthin is used as readout and a proof of concept for the application of SV in industry. We report here that complex SVs, including a pericentric inversion and a trans-chromosomes translocation between synV and synX, result in two neochromosomes and a 2.7-fold yield of astaxanthin. We demonstrated that inversion and inversion reshaped chromosomes 3D architecture and led to large reorganization of the genetic information nearby the breakpoint of the SVs along the chromosomes. Specifically, the pericentric inversion increased the expression of STE18 and the trans-chromosomic translocation increased the expression of RPS5 and MCM22, which contributed to higher astaxanthin yield. We also used the model learned from the aforementioned random screen and successfully harnessed the precise introduction of trans-chromosomes translocation and pericentric inversions by rational design. Overall, our work provides an effective tool to not only accelerate the directed genome evolution but also reveal mechanistic insight of complex SVs for altering phenotypes.

synthetic biology↗

Mouse Antibodies with Activity Against the SARS-CoV-2 D614G and B.1.351 Variants

With the rapid spread of SARS-CoV-2 variants, including those that are resistant to antibodies authorized for emergency use, it is apparent that new antibodies may be needed to effectively protect patients against more severe disease. Differences between the murine and human antibody repertoires may allow for the isolation of murine monoclonal antibodies that recognize a different or broader range of SARS-CoV-2 variants than the human antibodies that have been characterized so far. We describe mouse antibodies B13 and O24 that demonstrate neutralizing potency against SARS-CoV-2 Wuhan (D614G) and B.1.351 variants. Such murine antibodies may have advantages in protecting against severe symptoms when individuals are exposed to new SARS-CoV-2 variants.

molecular biology↗

Co-localization of different Neurotransmitter Transporters on the same Synaptic Vesicle is Bona-fide yet Sparse

Vesicular transporters (VTs) define the type of neurotransmitter that synaptic vesicles (SVs) store and release. While certain neurons in mammalian brain release multiple transmitters, the prevalence, physiology of such pluralism and if the release occurs from same or distinct vesicle pools is not clear. Using quantitative single vesicle imaging, we show that a small population of neuronal SVs indeed contain different VTs to accomplish corelease. Surprisingly, this population is highly diverse (27 types), expressing distinct dual transporters suggesting corelease of various combinations of neurotransmitters. Using glutamatergic vesicles as an example, we demonstrate that transporter colocalization not only determine the transmitter type but also influences the SV content and synaptic quantal size. Thus, presence of diverse transporters on the same vesicle is bona-fide and, depending on the VT types, this may act as one mechanism to regulate neurotransmitter type, content and release in space and time.

neuroscience↗