Biology subjects

Huang, Y.

Publications and source records attributed to Huang, Y..

At least 793 records · Page 44Linked to original sources

bioRxiv2021

DHA but not EPA induces the trans-differentiation of C2C12 cells into white-like adipocytes phenotype

Muscle derived stem cells (MDSCs) and myoblast play an important role in myotube regeneration when muscle tissue is injured. However, these cells can be induced to differentiate into adipocytes once exposed to PPAR{gamma} activator like EPA and DHA that are highly suggested during pregnancy. The objective of this study aims at determining the identity of trans-differentiated cells by exploring the effect of EPA and DHA on C2C12 undergoing differentiation into brown and white adipocytes. DHA but not EPA committed C2C12 cells reprograming into white like adipocyte phenotype. Also, DHA promoted the expression of lipolysis regulating genes but had no effect on genes regulating {beta}-oxidation referring to its implication in lipid re-esterification. Furthermore, DHA impaired C2C12 cells differentiation into brown adipocytes through reducing the thermogenic capacity and mitochondrial biogenesis of derived cells independent of UCP1. Accordingly, DHA treated groups showed an increased accumulation of lipid droplets and suppressed mitochondrial maximal respiration and spare respiratory capacity. EPA, on the other hand, reduced myogenesis regulating genes, but no significant differences were observed in the expression of adipogenesis key genes. Likewise, EPA suppressed the expression of WAT signature genes indicating that EPA and DHA have an independent role on white adipogeneis. Unlike DHA treatment, EPA supplementation had no effect on the differential of C2C12 cells into brown adipocytes. In conclusion, DHA is a potent adipogenic and lipogenic factor that can change the metabolic profile of muscle cells by increasing myocellular fat.

cell biology↗

bioRxiv2021

Community Evaluation of Glycoproteomics Informatics Solutions Reveals High-Performance Search Strategies of Glycopeptide Data

Glycoproteome profiling (glycoproteomics) is a powerful yet analytically challenging research tool. The complex tandem mass spectra generated from glycopeptide mixtures require sophisticated analysis pipelines for structural determination. Diverse software aiding the process have appeared, but their relative performance remains untested. Conducted through the HUPO Human Proteome Project - Human Glycoproteomics Initiative, this community study, comprising both developers and users of glycoproteomics software, evaluates the performance of informatics solutions for system-wide glycopeptide analysis. Mass spectrometry-based glycoproteomics datasets from human serum were shared with all teams. The relative team performance for N- and O-glycopeptide data analysis was comprehensively established and validated through orthogonal performance tests. Excitingly, several high-performance glycoproteomics informatics solutions were identified. While the study illustrated that significant informatics challenges remain, as indicated by a high discordance between annotated glycopeptides, lists of high-confidence (consensus) glycopeptides were compiled from the standardised team reports. Deep analysis of the performance data revealed key performance-associated search variables and led to recommendations for improved "high coverage" and "high accuracy" glycoproteomics search strategies. This study concludes that diverse software for comprehensive glycopeptide data analysis exist, points to several high-performance search strategies, and specifies key variables that may guide future software developments and assist informatics decision-making in glycoproteomics.

biochemistry↗

bioRxiv2021

Gait-phase modulates alpha and beta oscillations in the pedunculopontine nucleus

BackgroudThe pedunculopontine nucleus (PPN) is a reticular collection of neurons at the junction of the midbrain and pons, playing an important role in modulating posture and locomotion. Deep brain stimulation of the PPN has been proposed as an emerging treatment for patients with Parkinsons disease (PD) or multiple system atrophy (MSA) suffering gait-related atypical parkinsonian syndromes. ObjectiveIn this study, we investigated PPN activities during gait to better understand its functional role in locomotion. Specifically, we investigated whether PPN activity is rhythmically modulated during locomotion. MethodsPPN local field potential (LFP) activities were recorded from PD or MSA patients suffering from gait difficulties during stepping in place or free walking. Simultaneous measurements from force plates or accelerometers were used to determine the phase within each gait cycle at each time point. ResultsOur results showed that activities in the alpha and beta frequency bands in the PPN LFPs were rhythmically modulated by the gait phase within gait cycles, with a higher modulation index when the stepping rhythm was more regular. Meanwhile, the PPN-cortical coherence was most prominent in the alpha band. Both gait-phase related modulation in the alpha/beta power and the PPN-cortical coherence in the alpha frequency band were spatially specific to the PPN and did not extend to surrounding regions. ConclusionsThese results raise the possibility that alternating PPN stimulation in tandem with the gait rhythm may be more beneficial for gait control than continuous stimulation, although this remains to be established in future studies.

neuroscience↗

bioRxiv2021

A global multiregional proteomic map of the human cerebral cortex

The Brodmann area (BA)-based map is one of the most widely used cortical maps for studies of human brain functions and in clinical practice; however, the molecular architecture of BAs remain unknown. The present study provided a global multiregional proteomic map of the human cerebral cortex by analyzing 29 BAs. These 29 BAs were grouped into 6 clusters based on similarities in proteomic patterns: the motor and sensory cluster, vision cluster, auditory cluster and Brocas area, Wernickes area cluster, cingulate cortex cluster, and heterogeneous function cluster. We identified 474 cluster-specific and 134 BA-specific signature proteins whose functions are closely associated with specialized functions and disease vulnerability of the corresponding cluster or BA. The findings of the present study could provide explanations for the functional connections between the anterior cingulate cortex and sensorimotor cortex and for anxiety-related function in the sensorimotor cortex. The brain transcriptomic and proteomic comparison indicated that they both could reflect the function of cerebral cortex, but showed different characteristics. These proteomic data are publicly available at the Human Brain Proteome Atlas (www.brain-omics.com). Our results may enhance our understanding of the molecular basis of brain functions and provide an important resource to support human brain research.

neuroscience↗

bioRxiv2021

Brain expression quantitative trait locus and network analysis reveals downstream effects and putative drivers for brain-related diseases

Gaining insight into the downstream consequences of non-coding variants is an essential step towards the identification of therapeutic targets from genome-wide association study (GWAS) findings. Here we have harmonized and integrated 8,727 RNA-seq samples with accompanying genotype data from multiple brain-regions from 14 datasets. This sample size enabled us to perform both cis- and trans-expression quantitative locus (eQTL) mapping. Upon comparing the brain cortex cis-eQTLs (for 12,307 unique genes at FDR<0.05) with a large blood cis-eQTL analysis (n=31,684 samples), we observed that brain eQTLs are more tissue specific than previously assumed. We inferred the brain cell type for 1,515 cis-eQTLs by using cell type proportion information. We conducted Mendelian Randomization on 31 brain-related traits using cis-eQTLs as instruments and found 159 significant findings that also passed colocalization. Furthermore, two multiple sclerosis (MS) findings had cell type specific signals, a neuron-specific cis-eQTL for CYP24A1 and a macrophage specific cis-eQTL for CLECL1. To further interpret GWAS hits, we performed trans-eQTL analysis. We identified 2,589 trans-eQTLs (at FDR<0.05) for 373 unique SNPs, affecting 1,263 unique genes, and 21 replicated significantly using single-nucleus RNA-seq data from excitatory neurons. We also generated a brain-specific gene-coregulation network that we used to predict which genes have brain-specific functions, and to perform a novel network analysis of Alzheimers disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS) and Parkinsons disease (PD) GWAS data. This resulted in the identification of distinct sets of genes that show significantly enriched co-regulation with genes inside the associated GWAS loci, and which might reflect drivers of these diseases.

genomics↗

bioRxiv2021

Increased Resistance of SARS-CoV-2 Variant P.1 to Antibody Neutralization

The relative resistance of SARS-CoV-2 variants B.1.1.7 and B.1.351 to antibody neutralization has been described recently. We now report that another emergent variant from Brazil, P.1, is not only refractory to multiple neutralizing monoclonal antibodies, but also more resistant to neutralization by convalescent plasma (3.4 fold) and vaccinee sera (3.8-4.8 fold). The cryo-electron microscopy structure of a soluble prefusion-stabilized spike reveals the P.1 trimer to adopt exclusively a conformation in which one of the receptor-binding domains is in the "up" position, with the functional impact of mutations appearing to arise from local changes instead of global conformational alterations. The P.1 variant threatens current antibody therapies but less so the protective efficacy of our vaccines.

microbiology↗

bioRxiv2021

Pericentromeric heterochromatin impacts genome compartmentalization and sex chromosome evolution in a fish

Compartmentalization is one of the principles of chromosome 3D organization and has been suggested to be driven by the attraction of heterochromatin. The extent to which the pericentromeric heterochromatin (PCH) impacts chromosome compartmentalization is yet unclear. Here we produced a chromosome-level and fully phased diploid genome of an aquaculture fish, zig-zag eel (Mastacembelus armatus), and identified the centromeric and pericentromeric regions in the majority of chromosomes of both haploid genomes. The PCH is on average 4.2 Mb long, covering 17.7% of the chromosomes, and is the major target of histone 3 lysine 9 trimethylation (H3K9me3). In nearly half of the chromosomes, the PCH drives the chromosomes into two or three megascale chromatin domains with the PCH being a single one. We further demonstrate that PCH has a major impact in submetacentric, metacentric and small telocentric chromosomes in which the PCH drives the distribution of active and inactive compartments along the chromosomes. Additionally, we identified the young and homomorphic XY sex chromosomes that are submetacentric with the entire short-arm heterochromatinized. Interestingly, the sex-determining region seems to arise within the PCH that has been in place prior to the X-Y divergence and recombination suppression. Together, we demonstrate that the PCH can cover a considerably large portion of the chromosomes, and when it does so, it drives chromosome compartmentalization; and we propose a new model for the origin and evolution of homomorphic sex chromosomes in fish.

genomics↗

bioRxiv2021

Structural Basis for Accommodation of Emerging B.1.351 and B.1.1.7 Variants by Two Potent SARS-CoV-2 Neutralizing Antibodies

Emerging SARS-CoV-2 strains, B.1.1.7 and B.1.351, from the UK and South Africa, respectively show decreased neutralization by monoclonal antibodies and convalescent or vaccinee sera raised against the original wild-type virus, and are thus of clinical concern. However, the neutralization potency of two antibodies, 1-57 and 2-7, which target the receptor-binding domain (RBD) of spike, was unaffected by these emerging strains. Here, we report cryo-EM structures of 1-57 and 2-7 in complex with spike, revealing each of these antibodies to utilize a distinct mechanism to bypass or accommodate RBD mutations. Notably, each antibody represented a response with recognition distinct from those of frequent antibody classes. Moreover, many epitope residues recognized by 1-57 and 2-7 were outside hotspots of evolutionary pressure for both ACE2 binding and neutralizing antibody escape. We suggest the therapeutic use of antibodies like 1-57 and 2-7, which target less prevalent epitopes, could ameliorate issues of monoclonal antibody escape.

biochemistry↗

bioRxiv2021

Illustrating Potential Effects of Alternate Control Populations on Real-World Evidence-based Statistical Analyses

Case-control study designs are commonly used in retrospective analyses of Real-World Evidence (RWE). Due to the increasingly wide availability of RWE, it can be difficult to determine whether findings are robust or the result of testing multiple hypotheses. We investigate the potential effects of modifying cohort definitions in a case-control association study between depression and Type 2 Diabetes Mellitus (T2D). We found that small permutations to the criteria used to define the control population result in significant shifts in both the demographic structure of the identified cohort as well as the odds ratio of association. These differences remain present when testing against age and sex-matched controls. We believe this offers strong support for the need for robust guidelines, best practices and regulations around the use of observational RWE for clinical or regulatory decision making.

bioinformatics↗

bioRxiv2021

Identification and mechanistic analysis of an inhibitor of the CorC Mg2+ transporter

The CorC/CNNM family of Na+-dependent Mg2+ transporters is ubiquitously conserved from bacteria to humans. CorC, the bacterial member of the CorC/CNNM family of proteins, is involved in resistance to antibiotic exposure and in the survival of pathogenic microorganisms in their host environment. The CorC/CNNM family proteins possess a cytoplasmic region containing the regulatory ATP-binding site. While CorC and CNNM have attracted interest as therapeutic targets, inhibitors targeting the ir regulatory ATP-binding site have not yet been identified. Here, we performed a virtual screening of CorC by targeting its regulatory ATP-binding site, identified a chemical compound named IGN95a with inhibitory effects on both ATP binding and Mg2+ export, and determined the cytoplasmic domain structure in complex with IGN95a. Furthermore, a chemical cross-linking experiment indicated that with ATP bound to the cytoplasmic domain, the conformational equilibrium of CorC was shifted more towards the inward-facing state of the transmembrane domain. In contrast, IGN95a did not induce such a shift. Our results provide a structural basis for the further design and optimization of chemical compounds targeting the regulatory ATP-binding site of CorC as well as mechanistic insights into how ATP and chemical compounds modulate the transport activity of CorC.

biophysics↗

bioRxiv2021

Identification of a conserved neutralizing epitope present on spike proteins from highly pathogenic coronaviruses

Three pathogenic human coronaviruses have emerged within the last 20 years, with SARS-CoV-2 causing a global pandemic. Although therapeutic antibodies targeting the SARS-CoV-2 spike currently focus on the poorly conserved receptor-binding domain, targeting essential neutralizing epitopes on the more conserved S2 domain may provide broader protection. We report an antibody binding an epitope conserved in the pre-fusion core of MERS-CoV, SARS-CoV and SARS-CoV-2 spike S2 domains. Antibody 3A3 binds a conformational epitope with ~2.5 nM affinity and neutralizes spike from SARS-CoV, SARS-CoV-2 and variants of concern in in vitro pseudovirus assays. Hydrogen-deuterium exchange mass spectrometry identified residues 980-1006 in the flexible hinge region at the S2 apex as the 3A3 epitope, suggesting 3A3 prevents the S2 conformational rearrangements required for conversion to the spike post-fusion state and virus-host cell fusion. This work defines a conserved vulnerable site on the SARS-CoV-2 S2 domain and guides the design of pan-protective spike immunogens.

biochemistry↗

bioRxiv2021

Increased Resistance of SARS-CoV-2 Variants B.1.351 and B.1.1.7 to Antibody Neutralization

The COVID-19 pandemic has ravaged the globe, and its causative agent, SARS-CoV-2, continues to rage. Prospects of ending this pandemic rest on the development of effective interventions. Single and combination monoclonal antibody (mAb) therapeutics have received emergency use authorization1-3, with more in the pipeline4-7. Furthermore, multiple vaccine constructs have shown promise8, including two with ~95% protective efficacy against COVID-199,10. However, these interventions were directed toward the initial SARS-CoV-2 that emerged in 2019. The recent emergence of new SARS-CoV-2 variants B.1.1.7 in the UK11 and B.1.351 in South Africa12 is of concern because of their purported ease of transmission and extensive mutations in the spike protein. We now report that B.1.1.7 is refractory to neutralization by most mAbs to the N-terminal domain (NTD) of spike and relatively resistant to a few mAbs to the receptor-binding domain (RBD). It is not more resistant to convalescent plasma or vaccinee sera. Findings on B.1.351 are more worrisome in that this variant is not only refractory to neutralization by most NTD mAbs but also by multiple individual mAbs to the receptor-binding motif on RBD, largely due to an E484K mutation. Moreover, B.1.351 is markedly more resistant to neutralization by convalescent plasma (9.4 fold) and vaccinee sera (10.3-12.4 fold). B.1.351 and emergent variants13,14 with similar spike mutations present new challenges for mAb therapy and threaten the protective efficacy of current vaccines.

immunology↗

bioRxiv2021

Deep Learning Achieves Neuroradiologist-Level Performance in Detecting Hydrocephalus

PurposeIn large clinical centers a small subset of patients present with hydrocephalus that requires surgical treatment. We aimed to develop a screening tool to detect such cases from the head MRI with performance comparable to neuroradiologists. MethodsWe leveraged 496 clinical MRI exams collected retrospectively at a single clinical site from patients referred for any reason. This diagnostic dataset was enriched to have 259 hydrocephalus cases. A 3D convolutional neural network was trained on 16 manually segmented exams (ten hydrocephalus) and subsequently used to automatically segment the remaining 480 exams and extract volumetric anatomical features. A linear classifier of these features was trained on 240 exams to detect cases of hydrocephalus that required treatment with surgical intervention. Performance was compared to four neuroradiologists on the remaining 240 exams. Performance was also evaluated on a separate screening dataset of 451 exams collected from a routine clinical population to predict the consensus reading from four neuroradiologists using images alone. The pipeline was also tested on an external dataset of 31 exams from a 2nd clinical site. ResultsThe most discriminant features were the Magnetic Resonance Hydrocephalic Index (MRHI), ventricle volume, and the ratio between ventricle and brain volume. At matching sensitivity, the specificity of the machine and the neuroradiologists did not show significant differences for detection of hydrocephalus on either dataset (proportions test, p > 0.05). ROC performance compared favorably with the state-of-the-art (AUC 0.90-0.96), and replicated in the external validation. ConclusionHydrocephalus cases requiring treatment can be detected automatically from MRI in a heterogeneous patient population based on quantitative characterization of brain anatomy with performance comparable to that of neuroradiologists.

bioinformatics↗

bioRxiv2021

Nuclear m6A reader Ythdc1 regulates the scaffold function of LINE1 in mouse ESCs

N6-methyladenosine (m6A) on chromosome-associated regulatory RNAs (carRNAs), including repeat RNAs, play important roles in tuning the chromatin state and transcription1. Among diverse RNA-chromatin interacting modes, the nuclear RNA scaffold is considered important for trans-interactions2,3 but has not yet been connected with m6A yet. Here, we found that Ythdc1 played indispensable roles in the embryonic stem cell (ESC) self-renewal and differentiation potency, and these roles highly depended on its m6A-binding ability. Ythdc1 deficiency in ESCs resulted in decreased rRNA synthesis and the activation of 2-cell (2C) embryo-specific transcriptional program, and these observations recapitulated the transcriptome defects induced by dysfunction of the long interspersed nuclear element-1 (LINE1)-scaffold, which were unrelated to the direct targeting of Ythdc1. A detailed analysis revealed that Ythdc1 recognized m6A on LINE1 and was physically involved in the formation of the LINE1-Nucleolin partnership and the chromatin recruitment of Kap1. In summary, our study reveals a new link between m6A and the RNA scaffold and thus provides a new regulatory model for the crosstalk between RNA and the chromatin epigenome.

cell biology↗

bioRxiv2021

Potent SARS-CoV-2 Neutralizing Antibodies Directed Against Spike N-Terminal Domain Target a Single Supersite

Numerous antibodies that neutralize SARS-CoV-2 have been identified, and these generally target either the receptor-binding domain (RBD) or the N-terminal domain (NTD) of the viral spike. While RBD-directed antibodies have been extensively studied, far less is known about NTD-directed antibodies. Here we report cryo-EM and crystal structures for seven potent NTD-directed neutralizing antibodies in complex with spike or isolated NTD. These structures defined several antibody classes, with at least one observed in multiple convalescent donors. The structures revealed all seven antibodies to target a common surface, bordered by glycans N17, N74, N122, and N149. This site - formed primarily by a mobile {beta}-hairpin and several flexible loops - was highly electropositive, located at the periphery of the spike, and the largest glycan-free surface of NTD facing away from the viral membrane. Thus, in contrast to neutralizing RBD-directed antibodies that recognize multiple non-overlapping epitopes, potent NTD-directed neutralizing antibodies target a single supersite.

biochemistry↗

bioRxiv2021

Characterization of 475 novel, putative small RNAs (sRNAs) in Carbon-starved Salmonella enterica serovar typhimurium

An increasingly apparent role of noncoding RNA (ncRNAs) is to coordinate gene expression when bacteria faces various environmental stressors. Salmonella enterica, a well-studied foodborne pathogen, is known for its ability to survive in and adapt to various environmental challenges, making it a difficult pathogen to eliminate, as well as an important model for examining ncRNA contributions to cellular stress survival. A mounting body of evidence implicates small RNAs (sRNAs) as key drivers of Salmonella stress response. Generally thought to be 50-500 nucleotides in length and to occur mainly in intergenic regions, sRNAs regulate protein expression through base pairing with mRNA targets. Through employing a refined definition of sRNAs that allows for shorter sequences and for sRNA loci to overlap with annotated protein-coding gene loci, we have identified 475 previously unannotated sRNAs that are significantly differentially expressed during Carbon starvation (C-starvation). Northern blotting and quantitative RT-PCRs confirm the expressions and identities of several of these novel sRNAs. Additionally, our computational analyses find the majority to be highly conserved and structurally-related to known sRNAs. Importantly, we show that deletion of one of the dynamic sRNAs, sRNA4130247, significantly impairs the Salmonella C-starvation response (CSR), confirming its involvement (and suggesting the involvements of many other sRNAs identified in this work) in the Salmonella CSR. Strikingly, the 475 novel sRNAs identified in this study more than double the number of Salmonella enterica serovar Typhimurium SL1344 sRNAs described to date, increasing the total number of annotated Salmonella sRNAs from 396 to 871. In conclusion, the work presented here provides the first-ever characterization of intragenic sRNAs in Salmonella, experimentally confirms that sRNAs dynamically expressed during the CSR are directly involved in stress survival, and strongly suggests that sRNA loci likely outnumber those of protein-coding genes in Salmonella.

microbiology↗

bioRxiv2021

Artemisia annua L. extracts prevent in vitro replication of SARS-CoV-2

Ethnopharmacological relevanceArtemisia annua L. has been used for millennia in Southeast Asia to treat "fever". Many infectious microbial and viral diseases have been shown to respond to A. annua and communities around the world use the plant as a medicinal tea, especially for treating malaria. Aim of the StudySARS-CoV-2 (the cause of Covid-19) globally has infected and killed millions of people. Because of the broad-spectrum antiviral activity of artemisinin that includes blockade of SARS-CoV-1, we queried whether A. annua suppressed SARS-CoV-2. Materials and MethodsUsing Vero E6 and Calu-3 cells, we measured anti viral activity SARS-CoV-2 activity against fully infectious virusof dried leaf extracts of seven cultivars of A. annua sourced from four continents. IC50s were calculated and defined as (the concentrations that inhibited viral replication by 50%.) and CC50s (the concentrations that kill 50% of cells) were calculated. ResultsHot-water leaf extracts based on artemisinin, total flavonoids, or dry leaf mass showed antiviral activity with IC50 values of 0.1-8.7 M, 0.01-0.14 g, and 23.4-57.4 g, respectively. Antiviral efficacy did not correlate with artemisinin or total flavonoid contents of the extracts. One dried leaf sample was >12 years old, yet the hot-water extract was still found to be active. The UK and South African variants, B1.1.7 and B1.351, were similarly inhibited. While all hot water extracts were effective, concentrations of artemisinin and total flavonoids varied by nearly 100-fold in the extracts. Artemisinin alone showed an estimated IC50 of about 70 M, and the clinically used artemisinin derivatives artesunate, artemether, and dihydroartemisinin were ineffective or cytotoxic at elevated micromolar concentrations. In contrast, the antimalarial drug amodiaquine had an IC50 = 5.8 M. Extracts had minimal effects on infection of Vero E6 or Calu-3 cells by a reporter virus pseudotyped by the SARS-CoV-2 spike protein. There was no cytotoxicity within an order of magnitude above the antiviral IC90 values. ConclusionsA. annua extracts inhibit SARS-CoV-2 infection, and the active component(s) in the extracts is likely something besides artemisinin or a combination of components that block virus infection at a step downstream of virus entry. Further studies will determine in vivo efficacy to assess whether A. annua might provide a cost-effective therapeutic to treat SARS-CoV-2 infections. List of compounds studiedAmodiaquine Artemisinin Artesunate Artemether Deoxyartemisinin Dihydroartemisinin HighlightsO_LIArtemisia annua is effective in stopping replication of SARS-CoV-2 including 2 new variants. C_LIO_LIThe anti-viral effect does not correlate to artemisinin, nor to the total flavonoid content. C_LIO_LIThe anti-viral mechanism does not appear to involve blockade virus entry into cell. C_LIO_LIThe plant offers two additional benefits: a decreased inflammatory response and blunting of fibrosis. C_LIO_LIA. annua may provide a safe, low-cost alternative for treating patients infected with SARS-CoV-2. C_LI

microbiology↗

bioRxiv2021

Restoration of deficient DNA Repair Genes Mitigates Genome Instability and Increases Productivity of Chinese Hamster Ovary Cells

Chinese Hamster Ovary (CHO) cells are the primary host used for manufacturing of therapeutic proteins. However, production instability of high-titer cell lines is a major problem and is associated with genome instability, as chromosomal aberrations reduce transgene copy number and decrease protein titer. We analyzed whole-genome sequencing data from 11 CHO cell lines and found deleterious single-nucleotide polymorphisms (SNPs) in DNA repair genes. Comparison with other mammalian cells confirmed DNA repair is compromised in CHO. Restoration of key DNA repair genes by SNP reversal or expression of intact cDNAs improved DNA repair and genome stability. Moreover, the restoration of LIG4 and XRCC6 in a CHO cell line expressing secreted alkaline phosphatase mitigated transgene copy loss and improved protein titer retention. These results show for the first time that correction of key DNA repair genes yields considerable improvements in stability and protein expression in CHO, and provide new opportunities for cell line development and a more efficient and sustainable production of therapeutic proteins.

cell biology↗