The in vitro and in vivo antiviral effects of aloperine against Zika virus infection.

Zika virus (ZIKV) infection poses a significant threat to global public health and is associated with microcephaly. There are no approved ZIKV-specific vaccines or drugs for the clinical treatment of the infection. Currently, there are no approved ZIKV-specific vaccines or drugs for the clinical treatment of the infection. In this study, we investigated the antiviral potential of aloperine, a quinolizidine alkaloid, against ZIKV infection in vivo and in vitro. Our results demonstrate that aloperine effectively inhibits ZIKV infection in vitro, with a low nanomolar half maximal effective concentration (EC50 ). Specifically, aloperine strongly protected cells from ZIKV multiplication, as indicated by decreased expression of viral proteins and virus titer. Our further investigations using the time-of-drug-addition assay, binding, entry, and replication assays, detection of ZIKV strand-specific RNA, the cellular thermal shift assay, and molecular docking revealed that aloperine significantly inhibits the replication stage of the ZIKV life cycle by targeting the domain RNA-dependent RNA polymerase (RDRP) of ZIKV NS5 protein. Additionally, aloperine reduced viremia in mice and effectively lowered the mortality rate in infected mice. These findings highlight the potency of aloperine and its ability to target ZIKV infection, suggesting its potential as a promising antiviral drug against ZIKV.

Super-enhancer-driven Sorting Nexin 5 expression promotes dopaminergic neuronal ferroptosis in Parkinson's disease models.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease worldwide. Recent studies revealed that the ferroptosis pathway is involved in the death process of dopaminergic neurons in PD. The aberrant endosomal sorting pathway, which results in aberrant iron level in eukaryotic cells, may serve a role in the ferroptosis pathway in PD condition. However, its specific molecular mechanisms remained unclear. In the present study, we performed chromatin immunoprecipitation (ChIP) assay, the rank ordering of super-enhancers (ROSE) algorithm, and RNA interference (RNAi) to explore the regulatory mechanism of PD-specific super-enhancer (SE) in the endosomal sorting pathway and ferroptosis pathway of 6-OHDA-lesioned rats and cells. The ChIP assay and ROSE algorithm results showed that there are specific SEs expression in 6-OHDA-lesioned SNc of PD rats, and the most significant expression gene is Sorting Nexin 5 (SNX5). SNX5 silencing by RNAi experiments significantly decreased the level of ferroptosis in 6-OHDA-lesioned PC12 cells, suggesting the correlation between the SNX5, ferroptosis, and PD. In conclusion, this study investigated the mechanism by which PD-specific SE driven SNX5 promoted the ferroptosis level in PD models. This study further improved the understanding of the mechanism of ferroptosis during PD injury and provided potential therapeutic targets and clinical diagnostic markers in PD condition.

Plasma small ncRNA pair panels as novel biomarkers for early-stage lung adenocarcinoma screening.

BACKGROUND: Lung cancer is a major cause of cancer-related mortality worldwide, and around two-thirds of patients have metastasis at diagnosis. Thus, detecting lung cancer at an early stage could reduce mortality. Aberrant levels of circulating small non-coding RNAs (small ncRNAs) are potential diagnostic or prognostic markers for lung cancer. We aimed to identify plasma small ncRNA pairs that could be used for early screening and detection of lung adenocarcinoma (LAC). RESULTS: A panel of seven small ncRNA pair ratios could differentiate patients with LAC or benign lung disease from high-risk controls with an area under the curve (AUC) of 100.0%, a sensitivity of 100.0% and a specificity of 100.0% at the training stage (which included 50 patients with early-stage LAC, 35 patients with benign diseases and 29 high-risk controls) and an AUC of 90.2%, a sensitivity of 91.5% and a specificity of 80.4% at the validation stage (which included 44 patients with early-stage LAC, 32 patients with benign diseases and 51 high-risk controls). The same panel could distinguish LAC from high-risk controls with an AUC of 100.0%, a sensitivity of 100.0% and a specificity of 100.0% at the training stage and an AUC of 89.5%, a sensitivity of 85.4% and a specificity of 83.3% at the validation stage. Another panel of five small ncRNA pair ratios (different from the first) was able to differentiate LAC from benign disease with an AUC of 82.0%, a sensitivity of 81.1% and a specificity of 78.1% in the training cohort and an AUC of 74.2%, a sensitivity of 70.4% and a specificity of 72.7% in the validation cohort. CONCLUSIONS: Several small ncRNA pair ratios were identified as markers capable of discerning patients with LAC from those with benign lesions or high-risk control individuals.

Phylogeny and evolutionary radiation of the marine mussels (Bivalvia: Mytilidae) based on mitochondrial and nuclear genes.

The marine mussels (Mytilidae) are distributed in the oceans worldwide and occupy various habitats with diverse life styles. However, their taxonomy and phylogeny remain unclear from genus to family level due to equivocal morphological and anatomical characters among some taxa. In this study, we inferred the deep phylogenetic relationships among 42 mytiloid species, 19 genera, and five subfamilies of the extant marine mussels by using two mitochondrial (COI and 16S rRNA) and three nuclear (18S and 28S rRNA, and histone H3) genes. Phylogeny was reconstructed with a combination of five genes using Bayesian inference and maximum likelihood method, and divergence time was estimated for the major nodes using a relaxed clock model with three fossil calibrations. Phylogenetic trees revealed two major clades (Clades 1 and 2). In Clade 1, the deep-sea mussels (subfamily Bathymodiolinae) were sister to subfamily Modiolinae (represented by Modiolus), and then was clustered with Leiosolenus (subfamily Lithophaginae). Clade 2 comprised Lithophaga (Lithophaginae) and subfamily Mytilinae. Additionally, a Modiolus species and Musculus senhousia (subfamily Crenellinae) were positioned within the subfamily Mytilinae. The phylogenetic results strongly indicated monophyly of Mytilidae and Bathymodiolinae, polyphyly of Modiolinae and Lithophaginae, and paraphyly of Mytilinae. Divergence time estimation showed an ancient and gradual divergence in most mussel groups, whereas the deep-sea mussels originated recently and diverged rapidly during the Paleogene. The present study provides new insight into the evolutionary history of the marine mussels, and supports taxonomic revision for this important bivalve group.

Positive selection adaptation of two-domain arginine kinase (AK) from cold seep Vesicomyidae clams.

Arginine kinase (AK) is an important member of Phosphagen kinases which engage in energy metabolism process, and AKs from cold seep clams may develop an effective mechanism to adapt a special habitat (e.g. low temperature). Three Vesicomyidae clams and seven Veneridae clams (belong to the same Order Veneroida) were chosen to analyze the evolution of two-domain AKs. In the present study, ten two-domain AKs were identified and Neighbor-joining tree showed that AKs were divided into two groups. Branch-site model indicated that two-domain AKs were subjected to strong positive selection (ω2a = 17.5058). 16 positively selective sites were detected and five of them showed posterior probabilities of 0.95 or more. Comparative analysis found that domain 2 might be suffered from more evolutionary selection pressure than domain 1, as most positively sites were located at domain 2. Residue Pro (positively selective site) (587P in ApAK) in domain 2 from all Vesicomyidae AKs might participate in change of the synergism and in the function of its cold-adapted characteristics. In conclusion, our studies provide evidence of positive Darwinian selection in the two-domain AKs family of Vesicomyidae clams, and may contribute to a better understanding of its adaptation mechanisms to cold seep habitats.

Characteristics of the Copper,Zinc Superoxide Dismutase of a Hadal Sea Cucumber (Paelopatides sp.) from the Mariana Trench.

Superoxide dismutases (SODs) are among the most important antioxidant enzymes and show great potential in preventing adverse effects during therapeutic trials. In the present study, cloning, expression, and characterization of a novel Cu,Zn superoxide dismutase (Ps-Cu,Zn-SOD) from a hadal sea cucumber (Paelopatides sp.) were reported. Phylogenetic analysis showed that Ps-Cu,Zn-SOD belonged to a class of intracellular SOD. Its Km and Vmax were 0.0258 ± 0.0048 mM and 925.1816 ± 28.0430 units/mg, respectively. The low Km value of this enzyme represents a high substrate affinity and can adapt to the low metabolic rate of deep sea organisms. The enzyme functioned from 0 °C to 80 °C with an optimal temperature of 40 °C. Moreover, the enzyme activity was maintained up to 87.12% at 5 °C. The enzyme was active at pH 4 to 12 with an optimal pH of 8.5. Furthermore, Ps-Cu,Zn-SOD tolerated high concentration of urea and GuHCl, resisted hydrolysis by proteases, and maintained stability at high pressure. All these features demonstrated that the deep sea Ps-Cu,Zn-SOD is a potential candidate for application to the biopharmaceutical field.

Differential immune response of vitellogenin gene to Vibrio anguillarum in noble scallop Chlamys nobilis and its correlation with total carotenoid content.

Vitellogenin (Vg), an egg yolk precursor protein, not only functions as a source of nutrients and a nonpolar molecular carrier that combine and transfer lipids, proteins, vitamin and carotenoids to oocytes during the oogenesis. but also links with the immune defense in many oviparous animals. To investigate whether Vg plays a immune defensive role in noble scallop Chlamys nobilis, an acute Vibrio anguillarum infection experiment was conducted in orange and brown scallops with different carotenoids content. qRT-PCR result showed that Vg transcripts were significantly up-regulated after challenge with V. anguillarum in orange and brown shell scallops compared to the control group and Vg expression reached the highest spot at 6 h, indicated that Vg possessed an immune function in the noble scallop. Interestingly, a significantly positive correlation between Vg transcript levels and total carotenoids content in the ovary was observed, indicating that Vg gene expression was up regulated by carotenoids. The results suggest that Vg is a potent immune protector and carotenoid may linked with Vg plays an important role in host immune system against pathogens in noble scallop C. nobilis.

Differential expression of CuZnSOD gene under low temperature stress in noble scallop Chlamys nobilis with different carotenoid content.

The noble scallop Chlamys nobilis belongs to a warm-water mollusk and has been cultured in the sea of southern China since 1980s'. However, accidents of massive mortality have often occurred during the winter, and one of the reasons could be accumulation of harmful reactive oxygen species caused by lower temperature. Carotenoids are well known for their anti-oxidant function. To investigate whether carotenoids do play a role in mollusks' antioxidant defense system under lower temperature stress, an acute lower temperature experiment was conducted by using two types of scallops: the orange with higher carotenoids content and the brown with lower carotenoids content. Their CuZnSOD gene was cloned, mRNA expression levels were determined, and SOD activity and carotenoids content were measured. The complete CuZnSOD cDNA consists of 1078 nucleotides with an open reading frame encoding 154 amino acid residues, which has high identity with that of its sister species Chlamys farreri. The mRNA expression levels in both the mantle and gill from the orange scallops were significantly higher (P < 0.05) than that of the brown ones, but the result was the opposite in the blood. SOD activity in the mantle and gill from the orange scallops was significantly higher than (P < 0.05) that from the brown ones. Further, significantly positive correlations were found among CuZnSOD gene transcript levels, SOD activity and total carotenoids content in the orange scallops. The present results suggested that carotenoids could play roles in antioxidant defense system by upregulating gene expression under lower temperature stress in the noble scallop.

A de novo transcriptome of the noble scallop, Chlamys nobilis, focusing on mining transcripts for carotenoid-based coloration.

BACKGROUND: The noble scallop Chlamys nobilis Reeve displays polymorphism in shell and muscle colors. Previous research showed that the orange scallops with orange shell and muscle had a significantly higher carotenoid content than the brown ones with brown shell and white muscle. There is currently a need to identify candidate genes associated with carotenoid-based coloration. RESULTS: In the present study, 454 GS-FLX sequencing of noble scallop transcriptome yielded 1,181,060 clean sequence reads, which were assembled into 49,717 isotigs, leaving 110,158 reads as the singletons. Of the 159,875 unique sequences, 11.84% isotigs and 9.35% singletons were annotated. Moreover, 3,844 SSRs and over 120,000 high confidence variants (SNPs and INDELs) were identified. Especially, one class B scavenge receptor termed SRB-like-3 was discovered to express only in orange scallops and absent in brown ones, suggesting a significant association with high carotenoid content. Down-regulation of SRB-like-3 mRNA by RNA interference remarkably decreased blood carotenoid, providing compelling evidence that SRB-like-3 is an ideal candidate gene controlling carotenoid deposition and determining orange coloration. CONCLUSION: Transcriptome analysis of noble scallop reveals a novel scavenger receptor significantly associated with orange scallop rich in carotenoid content. Our findings pave the way for further functional elucidation of this gene and molecular basis of carotenoid deposition in orange scallop.

Functional characterization of a Δ5-like fatty acyl desaturase and its expression during early embryogenesis in the noble scallop Chlamys nobilis Reeve.

Long-chain polyunsaturated fatty acids (LC-PUFAs) are essential in lots of important physiological processes, while, many marine species have no or limited ability of endogenous PUFA biosynthesis, normally due to the lack of key enzymes such as fatty acid desaturase (FAD). In this study, we isolated a scallop Chlamys nobilis cDNA with high homology to vertebrate FADs. Functional characterization in recombinant yeast Saccharomyces cerevisiae showed that scallop FAD exhibited Δ5-desaturation activity towards both saturated and PUFA substrates. Thus, it efficiently desaturated exogenously added PUFA C20:4(n - 3) and C20:3(n - 6) to C20:5(n - 3) (EPA) and C20:4(n - 6) (ARA) respectively. It also converted the yeast's endogenous C18:0 into C18:1(n - 13), and participated in the biosynthesis of non-methylene-interrupted FA by introducing a double bond to C20:3(n - 3) and C20:2(n - 6) in the Δ5 carbon. Temporal transcript profile of scallop FAD was studied during early embryonic development. High level of mRNA was found at the beginning of embryogenesis (egg) and noticeable decreases of were observed during larvae development, suggesting maternal FAD mRNA transfer to the embryo. Further, FAD transcripts were detected in all tissues analyzed, with the gonad and hepatopancreas showing the highest expression.

Cloning and respond of a cold shock domain protein (CnCSDP) gene to cold stress in noble scallop Chlamys nobilis (Bivalve: Pectinidae).

Cold shock domain proteins (CSDPs) play various roles in cellular processes, including adaptation to low temperature in mollusk. In this study, the cDNA encoding CSDP in noble scallop Chlamys nobilis was cloned (CnCSDP), and its transcript profile in cold-stressed orange and brown strains was analyzed using real-time RT-PCR. Bioinformatic analysis shows that the complete CnCSDP cDNA is 1,434 bp in length, consisting of a 5'-, and 3'-untranslated region of 86 and 466 bp, respectively, and a 882 bp open reading frame encoding 294 amino acids with an estimated molecular mass of 33.23 kDa and an isoelectric point of 9.72. Furthermore, CnCSDP has two consensus RNA binding domains, four DNA binding sites and four RGG repeats. CnCSDP transcripts amount in the blood of orange strain were significantly higher, while in the mantle were much lower than that of brown strain. In the cold-stressed orange strain, CnCSDP mRNA decreased dramatically in the blood and mantle, but was significantly up-regulated at 1 h, and progressively returned to its original levels in the gill. In the cold-stressed brown strain, CnCSDP transcripts were significantly up-regulated at 6 h in the blood, decreased dramatically in the mantle, while mostly maintained unchanged in the gill. Lastly, significantly positive correlation was found between the CnCSDP transcripts amount and total carotenoids content in the gill in both orange and brown strain. This study will be helpful for understanding the molecular mechanism underlying cold stress in noble scallop in the further.

Cloning and functional characterization of the oxidative squalene cyclase gene in the deep-sea holothurian Chiridota sp.

Saponins derived from holothurians have high potential medicinal value. However, the de novo synthesis of the derivatization of triterpenes is still unclear. Oxidative squalene cyclase (OSC) can catalyze 2,3-Oxidosqualene into diverse products that serve as important precursors for triterpene synthesis. However, the function of theOSCgene in Chiridotasp. hasnot been elucidated. In this study, an OSCgenederived from the deep-sea holothurianChiridota sp. was cloned and characterized functionally in a yeast system. The open reading frame of the OSC gene was 2086 bp, which encoded 695 amino acids. The Chiridota sp. OSC gene has a similarity of 66.89 % to the OSC of other holothurian species and 63.51 % to that of Acanthaster planci. The phylogenetic tree showed that the echinozoan OSCsclustered together, and then they formeda sister group to fungi and plant homologs. Chiridota sp. OSC catalyzed 2,3-Oxidosqualene into parkeol.Under high pressure, the relative enzymatic activity and stability of cyclase inChiridota sp. was higher than that in the shallow-sea holothurianStichopus horrens. The newly cloned OSC of Chiridota sp.provideskey information for the interpretation of the saponin synthesis pathway in deep-sea holothurians.

Srebp-1 bridges gonad development and lipid accumulation by regulating lipogenesis in noble scallop Chlamys nobilis.

In bivalve, development of female gonad is accompanied with accumulating lipids which provided energy resource for non-feeding larvae development. As the major transcriptional regulators of lipid metabolism, Srebps play pivotal role in lipid homeostasis during oogenesis. However, little work was conducted on Srebps function in bivalves. The noble scallop Chlamys nobilis accumulated large amount of lipids in its gonad during oogenesis. Here, we identified a single Srebp gene (named Srebp-1) with a high similarity to human Srebp-1c. Disrupting Srebp-1 with Betulin (inhibiting the maturation of Srebp protein) repressed expression of lipogenic genes and de novo lipogenesis, and resulted in reduction of gonad index and lipid deposition, suggesting a crucial role of Srebp-1 for gonad development and lipid synthesis in female gonad. Additionally, scallops with Srebp-1 disruption released fewer eggs with a reduction in their lipid content and D-larvae formation, revealing an impair of fecundity caused by Srebp-1 disruption. Cold exposure stimulated lipid accumulation which required Srebp-1 to regulate de novo lipogenesis and lipid uptake, providing a crosstalk of Srebp-1 activity and environmental variation on lipid accumulation in noble scallop. Thus, our study identified Srebp-1 as a central regulator coordinating the lipid synthesis and accumulation with gonad development in noble scallop.

Analytical performance evaluation of the Mindray enzymatic assay for hemoglobin A1c measurement.

Hemoglobin A1c (HbA1c) plays a crucial role in diabetes management. We aimed to evaluate the analytical performance of a new enzymatic method kit for HbA1c measurement. The performance of the enzymatic method, including precision, accuracy, and linearity, was evaluated. Moreover, the interference effect from conventional interferents, Hb derivatives, Hb variants, and common drugs were assessed. In addition, the agreement of HbA1c results was compared between enzymatic methods, cation-exchange high-performance liquid chromatography (HPLC), and immunoassays. The intra-assay, between-assay, and total precision of HbA1c were all lower than 2%. HbA1c showed good linearity within the range of 3.96-20.23%. The enzymatic assay yielded results consistent with the external quality control samples, with a bias of less than ± 6% from the target values. The enzymatic method showed no interference from bilirubin, intralipid, vitamin C, Hb derivatives, common Hb variants, as well as antipyretic analgesics and hypoglycemic drugs. The HbA1c results of the enzymatic assay showed good agreement and accuracy compared to those obtained from the HPLC method and the immunoassay. The enzymatic method kit performed on the BS-600M chemistry analyzer is a reliable and robust method for measuring HbA1c. It is suitable for routine practice in clinical chemistry laboratories.

Epigenetic regulation of p63 blocks squamous-to-neuroendocrine transdifferentiation in esophageal development and malignancy.

While cell fate determination and maintenance are important in establishing and preserving tissue identity and function during development, aberrant cell fate transition leads to cancer cell heterogeneity and resistance to treatment. Here, we report an unexpected role for the transcription factor p63 (Trp63/TP63) in the fate choice of the squamous versus neuroendocrine lineage in esophageal development and malignancy. Deletion of p63 results in extensive neuroendocrine differentiation in the developing mouse esophagus and esophageal progenitors derived from human embryonic stem cells. In human esophageal neuroendocrine carcinoma (eNEC) cells, p63 is transcriptionally silenced by EZH2-mediated H3K27 trimethylation (H3K27me3). Up-regulation of the major p63 isoform ΔNp63α, through either ectopic expression or EZH2 inhibition, promotes squamous transdifferentiation of eNEC cells. Together, these findings uncover p63 as a rheostat in coordinating the transition between squamous and neuroendocrine cell fates during esophageal development and tumor progression.

Genetic adaptations of sea anemone to hydrothermal environment.

Hydrothermal vent habitats are characterized by high hydrostatic pressure, darkness, and the continuous release of toxic metal ions into the surrounding environment where sea anemones and other invertebrates thrive. Nevertheless, the understanding of metazoan metal ion tolerances and environmental adaptations remains limited. We assembled a chromosome-level genome for the vent sea anemone, Alvinactis idsseensis sp. nov. Comparative genomic analyses revealed gene family expansions and gene innovations in A. idsseensis sp. nov. as a response to high concentrations of metal ions. Impressively, the metal tolerance proteins MTPs is a unique evolutionary response to the high concentrations of Fe2+ and Mn2+ present in the environments of these anemones. We also found genes associated with high concentrations of polyunsaturated fatty acids that may respond to high hydrostatic pressure and found sensory and circadian rhythm-regulated genes that were essential for adaptations to darkness. Overall, our results provide insights into metazoan adaptation to metal ions, high pressure, and darkness in hydrothermal vents.

IL16 Regulates Osteoarthritis Progression as a Target Gene of Novel-miR-81.

OBJECTIVE: Functional polymorphisms of interleukin 16 (IL16) have been reported to be closely related to the risk of osteoarthritis (OA). However, how IL16 affects OA remains unclear. In this study, the role of IL16 in OA and the possible mechanisms were examined. METHODS: We established a meniscal/ligament injury (MLI) post-traumatic OA model in Sprague Dawley rats and an IL1ß-induced ADTC5 cells OA model. We detected the expression of IL16, novel-miR-81, MMP3, and MMP13 by quantitative real-time polymerase chain reaction. Western blot was performed to detect the expression of IL16, MMP3, and MMP13. The association between IL16 and novel-miR-81 was confirmed by luciferase reporter assay. Hematoxylin and eosin staining, Safranin O and Fast Green staining, and immunohistochemical staining were performed to clarify the effect of intra-articular injection of novel-miR-81 agomir in rats OA model. RESULTS: IL16 was upregulated in OA model. Knockdown of IL16 and overexpression of novel-miR-81 downregulated the expression of MMP3 and MMP13. Importantly, IL16 was a key target of novel-miR-81. Intra-articular injection of novel-miR-81 agomir could attenuate OA progression in rats OA model. CONCLUSION: Novel-miR-81 targeted IL16 to relieve OA, suggesting that novel-miR-81and IL16 may be new therapeutic targets for OA.

Berberine blocks inflammasome activation and alleviates diabetic cardiomyopathy via the miR­18a­3p/Gsdmd pathway.

Diabetic cardiomyopathy (DCM) is a cardiovascular disease which has been reported as a major cause of mortality worldwide for several years. Berberine (BBR) is a natural compound extracted from a Chinese herb, with a clinically reported anti­DCM effect; however, its molecular mechanisms have not yet been fully elucidated. The present study indicated that BBR markedly alleviated DCM by inhibiting IL­1ß secretion and the expression of gasdermin D (Gsdmd) at the post­transcriptional level. Considering the importance of microRNAs (miRNAs/miRs) in the regulation of the post­transcriptional process of specific genes, the ability of BBR to upregulate the expression levels of miR­18a­3p by activating its promoter (­1,000/­500) was examined. Notably, miR­18a­3p targeted Gsdmd and abated pyroptosis in high glucose­treated H9C2 cells. Moreover, miR­18a­3p overexpression inhibited Gsdmd expression and improved biomarkers of cardiac function in a rat model of DCM. On the whole, the findings of the present study indicate that BBR alleviates DCM by inhibiting miR­18a­3p­mediated Gsdmd activation; thus, BBR may be considered a potential therapeutic agent for the treatment of DCM.

A local translation program regulates centriole amplification in the airway epithelium.

Biogenesis of organelles requires targeting of a subset of proteins to specific subcellular domains by signal peptides or mechanisms controlling mRNA localization and local translation. How local distribution and translation of specific mRNAs for organelle biogenesis is achieved remains elusive and likely to be dependent on the cellular context. Here we identify Trinucleotide repeat containing-6a (Tnrc6a), a component of the miRNA pathway, distinctively localized to apical granules of differentiating airway multiciliated cells (MCCs) adjacent to centrioles. In spite of being enriched in TNRC6A and the miRNA-binding protein AGO2, they lack enzymes for mRNA degradation. Instead, we found these apical granules enriched in components of the mRNA translation machinery and newly synthesized proteins suggesting that they are specific hubs for target mRNA localization and local translation in MCCs. Consistent with this, Tnrc6a loss of function prevented formation of these granules and led to a broad reduction, rather than stabilization of miRNA targets. These included downregulation of key genes involved in ciliogenesis and was associated with defective multicilia formation both in vivo and in primary airway epithelial cultures. Similar analysis of Tnrc6a disruption in yolk sac showed stabilization of miRNA targets, highlighting the potential diversity of these mechanisms across organs.

Epigenetic regulation of p63 blocks squamous-to-neuroendocrine transdifferentiation in esophageal development and malignancy.

While cell fate determination and maintenance are important in establishing and preserving tissue identity and function during development, aberrant cell fate transition leads to cancer cell heterogeneity and resistance to treatment. Here, we report an unexpected role for the transcription factor p63 (Trp63/TP63) in the fate choice of squamous versus neuroendocrine lineage in esophageal development and malignancy. Deletion of p63 results in extensive neuroendocrine differentiation in the developing mouse esophagus and esophageal progenitors derived from human embryonic stem cells. In human esophageal neuroendocrine carcinoma (eNEC) cells, p63 is transcriptionally silenced by EZH2-mediated H3K27 trimethylation (H3K27me3). Upregulation of the major p63 isoform ΔNp63α, through either ectopic expression or EZH2 inhibition, promotes squamous transdifferentiation of eNEC cells. Together these findings uncover p63 as a rheostat in coordinating the transition between squamous and neuroendocrine cell fates during esophageal development and tumor progression.