DNA cytosine methyltransferases differentially regulate genome-wide hypermutation and interhomolog recombination in Trichoderma reesei meiosis.

Trichoderma reesei is an economically important enzyme producer with several unique meiotic features. spo11, the initiator of meiotic double-strand breaks (DSBs) in most sexual eukaryotes, is dispensable for T. reesei meiosis. T. reesei lacks the meiosis-specific recombinase Dmc1. Rad51 and Sae2, the activator of the Mre11 endonuclease complex, promote DSB repair and chromosome synapsis in wild-type and spo11Δ meiosis. DNA methyltransferases (DNMTs) perform multiple tasks in meiosis. Three DNMT genes (rid1, dim2 and dimX) differentially regulate genome-wide cytosine methylation and C:G-to-T:A hypermutations in different chromosomal regions. We have identified two types of DSBs: type I DSBs require spo11 or rid1 for initiation, whereas type II DSBs do not rely on spo11 and rid1 for initiation. rid1 (but not dim2) is essential for Rad51-mediated DSB repair and normal meiosis. rid1 and rad51 exhibit a locus heterogeneity (LH) relationship, in which LH-associated proteins often regulate interconnectivity in protein interaction networks. This LH relationship can be suppressed by deleting dim2 in a haploid rid1Δ (but not rad51Δ) parental strain, indicating that dim2 and rid1 share a redundant function that acts earlier than rad51 during early meiosis. In conclusion, our studies provide the first evidence of the involvement of DNMTs during meiotic initiation and recombination.

Trichoderma reesei Rad51 tolerates mismatches in hybrid meiosis with diverse genome sequences.

Most eukaryotes possess two RecA-like recombinases (ubiquitous Rad51 and meiosis-specific Dmc1) to promote interhomolog recombination during meiosis. However, some eukaryotes have lost Dmc1. Given that mammalian and yeast Saccharomyces cerevisiae (Sc) Dmc1 have been shown to stabilize recombination intermediates containing mismatches better than Rad51, we used the Pezizomycotina filamentous fungus Trichoderma reesei to address if and how Rad51-only eukaryotes conduct interhomolog recombination in zygotes with high sequence heterogeneity. We applied multidisciplinary approaches (next- and third-generation sequencing technology, genetics, cytology, bioinformatics, biochemistry, and single-molecule biophysics) to show that T. reesei Rad51 (TrRad51) is indispensable for interhomolog recombination during meiosis and, like ScDmc1, TrRad51 possesses better mismatch tolerance than ScRad51 during homologous recombination. Our results also indicate that the ancestral TrRad51 evolved to acquire ScDmc1-like properties by creating multiple structural variations, including via amino acid residues in the L1 and L2 DNA-binding loops.

Drosophila Phosphatase of Regenerating Liver Is Critical for Photoreceptor Cell Polarity and Survival during Retinal Development.

Establishing apicobasal polarity, involving intricate interactions among polarity regulators, is key for epithelial cell function. Though phosphatase of regenerating liver (PRL) proteins are implicated in diverse biological processes, including cancer, their developmental role remains unclear. In this study, we explore the role of Drosophila PRL (dPRL) in photoreceptor cell development. We reveal that dPRL, requiring a C-terminal prenylation motif, is highly enriched in the apical membrane of developing photoreceptor cells. Moreover, dPRL knockdown during retinal development results in adult Drosophila retinal degeneration, caused by hid-induced apoptosis. dPRL depletion also mislocalizes cell adhesion and polarity proteins like Armadillo, Crumbs, and DaPKC and relocates the basolateral protein, alpha subunit of Na+/K+-ATPase, to the presumed apical membrane. Importantly, this polarity disruption is not secondary to apoptosis, as suppressing hid expression does not rescue the polarity defect in dPRL-depleted photoreceptor cells. These findings underscore dPRL's crucial role in photoreceptor cell polarity and emphasize PRL's importance in establishing epithelial polarity and maintaining cell survival during retinal development, offering new insights into PRL's role in normal epithelium.

Novel long-acting ropeginterferon alfa-2b: Pharmacokinetics, pharmacodynamics and safety in a phase I clinical trial.

AIMS: Ropeginterferon alfa-2b is a novel, long-acting pegylated interferon alfa-2b. We aimed to evaluate its safety, pharmacokinetics (PK) and pharmacodynamics (PD). METHODS: Thirty-six subjects received single subcutaneous injection of ropeginterferon alfa-2b at doses ranging from 24 to 270 µg, and 12 subjects received pegylated IFN alfa-2a subcutaneously at 180 µg. Primary endpoints were safety/PK profiles of ropeginterferon alfa-2b, while secondary endpoints were to compare PK/PD parameters with pegylated IFN alfa-2a. RESULTS: Adverse events in ropeginterferon alfa-2b and pegylated IFN alfa-2a groups were similar, and most of them were mild or moderate. Mean Cmax increased from 1.78 to 24.84 ng/mL along with the dose escalations in ropeginterferon alfa-2b groups and was 12.95 ng/mL for pegylated IFN alfa-2a. At 180 µg, ropeginterferon alfa-2b showed statistically significant Cmax geometric mean ratio (1.76; P = .0275). Mean Tmax ranged from 74.52 to 115.69 h for ropeginterferon alfa-2b groups, and was 84.25 h for pegylated IFN alfa-2a. Mean AUC0-t increased from 372.3 to 6258 ng•h/mL with the dose escalations in the ropeginterferon alfa-2b groups, while for pegylated IFN alfa-2a it was found to be 2706 ng•h/mL in pegylated IFN alfa-2a. For neopterin and 2',5'-oligoadenylate synthase, mean Emax , Tmax and AUC0-t of ropeginterferon alfa-2b were similar to those of pegylated IFNα-2a at 180 µg. CONCLUSION: Ropeginterferon alfa-2b up to 270 µg was safe and well tolerated. The PK/PD parameters of ropeginterferon alfa-2b showed increase in dose-response. Ropeginterferon alfa-2b had higher drug exposures and showed similar safety profile when compared to pegylated IFN alfa-2a at the same dose level.

Dual roles of yeast Rad51 N-terminal domain in repairing DNA double-strand breaks.

Highly toxic DNA double-strand breaks (DSBs) readily trigger the DNA damage response (DDR) in cells, which delays cell cycle progression to ensure proper DSB repair. In Saccharomyces cerevisiae, mitotic S phase (20-30 min) is lengthened upon DNA damage. During meiosis, Spo11-induced DSB onset and repair lasts up to 5 h. We report that the NH2-terminal domain (NTD; residues 1-66) of Rad51 has dual functions for repairing DSBs during vegetative growth and meiosis. Firstly, Rad51-NTD exhibits autonomous expression-enhancing activity for high-level production of native Rad51 and when fused to exogenous ß-galactosidase in vivo. Secondly, Rad51-NTD is an S/T-Q cluster domain (SCD) harboring three putative Mec1/Tel1 target sites. Mec1/Tel1-dependent phosphorylation antagonizes the proteasomal degradation pathway, increasing the half-life of Rad51 from ∼30 min to ≥180 min. Our results evidence a direct link between homologous recombination and DDR modulated by Rad51 homeostasis.

Drosophila decapping protein 2 modulates the formation of cortical F-actin for germ plasm assembly.

In Drosophila, the deposition of the germ plasm at the posterior pole of the oocyte is essential for the abdomen and germ cell formation during embryogenesis. To assemble the germ plasm, oskar (osk) mRNA, produced by nurse cells, should be localized and anchored on the posterior cortex of the oocyte. Processing bodies (P-bodies) are cytoplasmic RNA granules responsible for the 5'-3' mRNA degradation. Evidence suggests that the components of P-bodies, such as Drosophila decapping protein 1 and Ge-1, are involved in the posterior localization of osk. However, whether the decapping core enzyme, Drosophila decapping protein 2 (dDcp2), is also involved remains unclear. Herein, we generated a dDcp2 null allele and showed that dDcp2 was required for the posterior localization of germ plasm components including osk. dDcp2 was distributed on the oocyte cortex and was localized posterior to the osk. In the posterior pole of dDcp2 mutant oocytes, osk was mislocalized and colocalized with F-actin detached from the cortex; moreover, considerably fewer F-actin projections were observed. Using the F-actin cosedimentation assay, we proved that dDcp2 interacted with F-actin through its middle region. In conclusion, our findings explored a novel function of dDcp2 in assisting osk localization by modulating the formation of F-actin projections on the posterior cortex.

Budding yeast Rad51: a paradigm for how phosphorylation and intrinsic structural disorder regulate homologous recombination and protein homeostasis.

The RecA-family recombinase Rad51 is the central player in homologous recombination (HR), the faithful pathway for repairing DNA double-strand breaks (DSBs) during both mitosis and meiosis. The behavior of Rad51 protein in vivo is fine-tuned via posttranslational modifications conducted by multiple protein kinases in response to cell cycle cues and DNA lesions. Unrepaired DSBs and ssDNA also activate Mec1ATR and Tel1ATM family kinases to initiate the DNA damage response (DDR) that safeguards genomic integrity. Defects in HR and DDR trigger genome instability and result in cancer predisposition, infertility, developmental defects, neurological diseases or premature aging. Intriguingly, yeast Mec1ATR- and Tel1ATM-dependent phosphorylation promotes Rad51 protein stability during DDR, revealing how Mec1ATR can alleviate proteotoxic stress. Moreover, Mec1ATR- and Tel1ATM-dependent phosphorylation also occurs on DDR-unrelated proteins, suggesting that Mec1ATR and Tel1ATM have a DDR-independent function in protein homeostasis. In this minireview, we first describe how human and budding yeast Rad51 are phosphorylated by multiple protein kinases at different positions to promote homology-directed DNA repair and recombination (HDRR). Then, we discuss recent findings showing that intrinsic structural disorder and Mec1ATR/Tel1ATM-dependent phosphorylation are coordinated in yeast Rad51 to regulate both HR and protein homeostasis.

Tlr7 deletion alters expression profiles of genes related to neural function and regulates mouse behaviors and contextual memory.

The neuronal innate immune system recognizes endogenous danger signals and regulates neuronal development and function. Toll-like receptor 7 (TLR7), one of the TLRs that trigger innate immune responses in neurons, controls neuronal morphology. To further assess the function of TLR7 in the brain, we applied next generation sequencing to investigate the effect of Tlr7 deletion on gene expression in hippocampal and cortical mixed cultures and on mouse behaviors. Since previous in vivo study suggested that TLR7 is more critical for neuronal morphology at earlier developmental stages, we analyzed two time-points (4 and 18 DIV) to represent young and mature neurons, respectively. At 4 DIV, Tlr7 KO neurons exhibited reduced expression of genes involved in neuronal development, synaptic organization and activity and behaviors. Some of these Tlr7-regulated genes are also associated with multiple neurological and neuropsychiatric diseases. TLR7-regulated transcriptomic profiles differed at 18 DIV. Apart from neuronal genes, genes related to glial cell development and differentiation became sensitive to Tlr7 deletion at 18 DIV. Moreover, Tlr7 KO mice exhibited altered behaviors in terms of anxiety, aggression, olfaction and contextual fear memory. Electrophysiological analysis further showed an impairment of long-term potentiation in Tlr7 KO hippocampus. Taken together, these results indicate that TLR7 regulates neural development and brain function, even in the absence of infectious or pathogenic molecules. Our findings strengthen evidence for the role of the neuronal innate immune system in fine-tuning neuronal morphology and activity and implicate it in neuropsychiatric disorders.

Repeat-induced point (RIP) mutation in the industrial workhorse fungus Trichoderma reesei.

Trichoderma reesei (syn. Hypocrea jecorina) is a filamentous ascomycete. Due to its capability of producing large amounts of lignocellulolytic enzymes and various heterologous proteins, this fungus has been widely used for industrial applications for over 70 years. It is also a model organism for lignocellulosic biomass degradation and metabolic engineering. Recently, we experimentally and computationally demonstrated that Trichoderma reesei exhibits high homology pairing and repeat-induced point (RIP) mutation activities at a premeiotic stage, i.e., between fertilization and karyogamy or premeiotic DNA replication. The discovery of RIP in Trichoderma reesei not only reveals significant impacts of sexual reproduction on evolution and chromosome architecture but also provides intriguing perspectives for industrial strain improvement. This review emphasizes two major points about RIP and RIP-like processes in Pezizomycotina fungi. First, the molecular mechanisms of RIP and RIP-like processes in Trichoderma reesei and other Pezizomycotina fungi are apparently distinct from those originally described in the model fungus Neurospora crassa. Second, orthologs of the rid1 (deficient in RIP-1) DNA methyltransferase gene were shown to be essential for sexual development in at least four Pezizomycotina fungi, including Trichoderma reesei. In contrast, rid1 is dispensable for Neurospora crassa sexual development. We suggest that the rid1-like gene products and/or their DNA methyltransferase activities play critical roles in promoting fungal sexual development. The Neurospora crassa rid1 gene might have lost this evolutionarily conserved function.

S. cerevisiae Mre11 recruits conjugated SUMO moieties to facilitate the assembly and function of the Mre11-Rad50-Xrs2 complex.

Double-strand breaks (DSBs) in chromosomes are the most challenging type of DNA damage. The yeast and mammalian Mre11-Rad50-Xrs2/Nbs1 (MRX/N)-Sae2/Ctp1 complex catalyzes the resection of DSBs induced by secondary structures, chemical adducts or covalently-attached proteins. MRX/N also initiates two parallel DNA damage responses-checkpoint phosphorylation and global SUMOylation-to boost a cell's ability to repair DSBs. However, the molecular mechanism of this SUMO-mediated response is not completely known. In this study, we report that Saccharomyces cerevisiae Mre11 can non-covalently recruit the conjugated SUMO moieties, particularly the poly-SUMO chain. Mre11 has two evolutionarily-conserved SUMO-interacting motifs, Mre11(SIM1) and Mre11(SIM2), which reside on the outermost surface of Mre11. Mre11(SIM1) is indispensable for MRX assembly. Mre11(SIM2) non-covalently links MRX with the SUMO enzymes (E2/Ubc9 and E3/Siz2) to promote global SUMOylation of DNA repair proteins. Mre11(SIM2) acts independently of checkpoint phosphorylation. During meiosis, the mre11(SIM2) mutant, as for mre11S, rad50S and sae2Δ, allows initiation but not processing of Spo11-induced DSBs. Using MRX and DSB repair as a model, our work reveals a general principle in which the conjugated SUMO moieties non-covalently facilitate the assembly and functions of multi-subunit protein complexes.

Omics Analyses of Trichoderma reesei CBS999.97 and QM6a Indicate the Relevance of Female Fertility to Carbohydrate-Active Enzyme and Transporter Levels.

The filamentous fungus Trichoderma reesei is found predominantly in the tropics but also in more temperate regions, such as Europe, and is widely known as a producer of large amounts of plant cell wall-degrading enzymes. We sequenced the genome of the sexually competent isolate CBS999.97, which is phenotypically different from the female sterile strain QM6a but can cross sexually with QM6a. Transcriptome data for growth on cellulose showed that entire carbohydrate-active enzyme (CAZyme) families are consistently differentially regulated between these strains. We evaluated backcrossed strains of both mating types, which acquired female fertility from CBS999.97 but maintained a mostly QM6a genetic background, and we could thereby distinguish between the effects of strain background and female fertility or mating type. We found clear regulatory differences associated with female fertility and female sterility, including regulation of CAZyme and transporter genes. Analysis of carbon source utilization, transcriptomes, and secondary metabolites in these strains revealed that only a few changes in gene regulation are consistently correlated with different mating types. Different strain backgrounds (QM6a versus CBS999.97) resulted in the most significant alterations in the transcriptomes and in carbon source utilization, with decreased growth of CBS999.97 on several amino acids (for example proline or alanine), which further correlated with the downregulation of genes involved in the respective pathways. In combination, our findings support a role of fertility-associated processes in physiology and gene regulation and are of high relevance for the use of sexual crossing in combining the characteristics of two compatible strains or quantitative trait locus (QTL) analysis.IMPORTANCETrichoderma reesei is a filamentous fungus with a high potential for secretion of plant cell wall-degrading enzymes. We sequenced the genome of the fully fertile field isolate CBS999.97 and analyzed its gene regulation characteristics in comparison with the commonly used laboratory wild-type strain QM6a, which is not female fertile. Additionally, we also evaluated fully fertile strains with genotypes very close to that of QM6a in order to distinguish between strain-specific and fertility-specific characteristics. We found that QM6a and CBS999.97 clearly differ in their growth patterns on different carbon sources, CAZyme gene regulation, and secondary metabolism. Importantly, we found altered regulation of 90 genes associated with female fertility, including CAZyme genes and transporter genes, but only minor mating type-dependent differences. Hence, when using sexual crossing in research and for strain improvement, it is important to consider female fertile and female sterile strains for comparison with QM6a and to achieve optimal performance.

Genomic and transcriptomic analyses of the medicinal fungus Antrodia cinnamomea for its metabolite biosynthesis and sexual development.

Antrodia cinnamomea, a polyporus mushroom of Taiwan, has long been used as a remedy for cancer, hypertension, and hangover, with an annual market of over $100 million (US) in Taiwan. We obtained a 32.15-Mb genome draft containing 9,254 genes. Genome ontology enrichment and pathway analyses shed light on sexual development and the biosynthesis of sesquiterpenoids, triterpenoids, ergostanes, antroquinonol, and antrocamphin. We identified genes differentially expressed between mycelium and fruiting body and 242 proteins in the mevalonate pathway, terpenoid pathways, cytochrome P450s, and polyketide synthases, which may contribute to the production of medicinal secondary metabolites. Genes of secondary metabolite biosynthetic pathways showed expression enrichment for tissue-specific compounds, including 14-α-demethylase (CYP51F1) in fruiting body for converting lanostane to ergostane triterpenoids, coenzymes Q (COQ) for antroquinonol biosynthesis in mycelium, and polyketide synthase for antrocamphin biosynthesis in fruiting body. Our data will be useful for developing a strategy to increase the production of useful metabolites.

Yeast axial-element protein, Red1, binds SUMO chains to promote meiotic interhomologue recombination and chromosome synapsis.

The synaptonemal complex (SC) is a tripartite protein structure consisting of two parallel axial elements (AEs) and a central region. During meiosis, the SC connects paired homologous chromosomes, promoting interhomologue (IH) recombination. Here, we report that, like the CE component Zip1, Saccharomyces cerevisiae axial-element structural protein, Red1, can bind small ubiquitin-like modifier (SUMO) polymeric chains. The Red1-SUMO chain interaction is dispensable for the initiation of meiotic DNA recombination, but it is essential for Tel1- and Mec1-dependent Hop1 phosphorylation, which ensures IH recombination by preventing the inter-sister chromatid DNA repair pathway. Our results also indicate that Red1 and Zip1 may directly sandwich the SUMO chains to mediate SC assembly. We suggest that Red1 and SUMO chains function together to couple homologous recombination and Mec1-Tel1 kinase activation with chromosome synapsis during yeast meiosis.

Mek1 stabilizes Hop1-Thr318 phosphorylation to promote interhomolog recombination and checkpoint responses during yeast meiosis.

Red1, Hop1 and Mek1 are three yeast meiosis-specific chromosomal proteins that uphold the interhomolog (IH) bias of meiotic recombination. Mek1 is also an effector protein kinase in a checkpoint that responds to aberrant DNA and/or axis structure. The activation of Mek1 requires Red1-dependent Hop1-Thr(T)318 phosphorylation, which is mediated by Mec1 and Tel1, the yeast homologs of the mammalian DNA damage sensor kinases ATR and ATM. As the ectopic expression of Mek1-glutathione S-transferase (GST) was shown to promote IH recombination in the absence of Mec1/Tel1-dependent checkpoint function, it was proposed that Mek1 might play dual roles during meiosis by directly phosphorylating targets that are involved in the recombination checkpoint. Here, we report that Mek1 has a positive feedback activity in the stabilization of Mec1/Tel1-mediated Hop1-T318 phosphorylation against the dephosphorylation mediated by protein phosphatase 4. Our results also reveal that GST-Mek1 or Mek1-GST further increases Hop1-T318 phosphorylation. This positive feedback function of Mek1 is independent of Mek1's kinase activity, but dependent on Mek1's forkhead-associated (FHA) domain and its arginine 51 residue. Arginine 51 directly mediates the interaction of Mek1-FHA and phosphorylated Hop1-T318. We suggest that the Hop1-Mek1 interaction is similar to the Rad53-Dun1 signaling pathway, which is mediated through the interaction of phosphorylated Rad53 and Dun1-FHA.

Noncanonical usage of stop codons in ciliates expands proteins with structurally flexible Q-rich motifs.

Serine(S)/threonine(T)-glutamine(Q) cluster domains (SCDs), polyglutamine (polyQ) tracts and polyglutamine/asparagine (polyQ/N) tracts are Q-rich motifs found in many proteins. SCDs often are intrinsically disordered regions that mediate protein phosphorylation and protein-protein interactions. PolyQ and polyQ/N tracts are structurally flexible sequences that trigger protein aggregation. We report that due to their high percentages of STQ or STQN amino acid content, four SCDs and three prion-causing Q/N-rich motifs of yeast proteins possess autonomous protein expression-enhancing activities. Since these Q-rich motifs can endow proteins with structural and functional plasticity, we suggest that they represent useful toolkits for evolutionary novelty. Comparative Gene Ontology (GO) analyses of the near-complete proteomes of 26 representative model eukaryotes reveal that Q-rich motifs prevail in proteins involved in specialized biological processes, including Saccharomyces cerevisiae RNA-mediated transposition and pseudohyphal growth, Candida albicans filamentous growth, ciliate peptidyl-glutamic acid modification and microtubule-based movement, Tetrahymena thermophila xylan catabolism and meiosis, Dictyostelium discoideum development and sexual cycles, Plasmodium falciparum infection, and the nervous systems of Drosophila melanogaster, Mus musculus and Homo sapiens. We also show that Q-rich-motif proteins are expanded massively in 10 ciliates with reassigned TAAQ and TAGQ codons. Notably, the usage frequency of CAGQ is much lower in ciliates with reassigned TAAQ and TAGQ codons than in organisms with expanded and unstable Q runs (e.g. D. melanogaster and H. sapiens), indicating that the use of noncanonical stop codons in ciliates may have coevolved with codon usage biases to avoid triplet repeat disorders mediated by CAG/GTC replication slippage.

Recent advances in biomimetic nanodelivery systems: New brain-targeting strategies.

In recent years, brain diseases have seriously threatened human health due to their high morbidity and mortality. Achieving efficient drug delivery to provide satisfactory therapeutic outcomes is currently the greatest challenge in treating brain diseases. The main challenges are the structural peculiarities of the brain and the inability to transport drugs across the blood-brain barrier. Biomimetic nanodelivery systems (BNDSs) applied to the brain have been extensively developed in the preclinical phase to surmount these challenges. Considering the inherent properties of BNDSs, the substantially enhanced ability of BNDS to carry therapeutic agents and their higher selectivity toward lesions offer new opportunities for developing safe and effective therapies. This review summarizes brain-targeting nanotherapies, particularly advanced therapies with biomimetic nano-assistance. Prospects for developing BNDSs and the challenges of their clinical translation are discussed. Understanding and implementing biomimetic nanotherapies may facilitate the development of new targeted strategies for brain disorders.

Phase separation and zinc-induced transition modulate synaptic distribution and association of autism-linked CTTNBP2 and SHANK3.

Many synaptic proteins form biological condensates via liquid-liquid phase separation (LLPS). Synaptopathy, a key feature of autism spectrum disorders (ASD), is likely relevant to the impaired phase separation and/or transition of ASD-linked synaptic proteins. Here, we report that LLPS and zinc-induced liquid-to-gel phase transition regulate the synaptic distribution and protein-protein interaction of cortactin-binding protein 2 (CTTNBP2), an ASD-linked protein. CTTNBP2 forms self-assembled condensates through its C-terminal intrinsically disordered region and facilitates SHANK3 co-condensation at dendritic spines. Zinc binds the N-terminal coiled-coil region of CTTNBP2, promoting higher-order assemblies. Consequently, it leads to reduce CTTNBP2 mobility and enhance the stability and synaptic retention of CTTNBP2 condensates. Moreover, ASD-linked mutations alter condensate formation and synaptic retention of CTTNBP2 and impair mouse social behaviors, which are all ameliorated by zinc supplementation. Our study suggests the relevance of condensate formation and zinc-induced phase transition to the synaptic distribution and function of ASD-linked proteins.

Sexual Crossing, Chromosome-Level Genome Sequences, and Comparative Genomic Analyses for the Medicinal Mushroom Taiwanofungus Camphoratus (Syn. Antrodia Cinnamomea, Antrodia Camphorata).

Taiwanofungus camphoratus mushrooms are a complementary and alternative medicine for hangovers, cancer, hypertension, obesity, diabetes, and inflammation. Though Taiwanofungus camphoratus has attracted considerable biotechnological and pharmacological attention, neither classical genetic nor genomic approaches have been properly established for it. We isolated four sexually competent monokaryons from two T. camphoratus dikaryons used for the commercial cultivation of orange-red (HC1) and milky-white (SN1) mushrooms, respectively. We also sequenced, annotated, and comparatively analyzed high-quality and chromosome-level genome sequences of these four monokaryons. These genomic resources represent a valuable basis for understanding the biology, evolution, and secondary metabolite biosynthesis of this economically important mushrooms. We demonstrate that T. camphoratus has a tetrapolar mating system and that HC1 and SN1 represent two intraspecies isolates displaying karyotypic variation. Compared with several edible mushroom model organisms, T. camphoratus underwent a significant contraction in the gene family and individual gene numbers, most notably for plant, fungal, and bacterial cell-wall-degrading enzymes, explaining why T. camphoratus mushrooms are rare in natural environments, are difficult and time-consuming to artificially cultivate, and are susceptible to fungal and bacterial infections. Our results lay the foundation for an in-depth T. camphoratus study, including precise genetic manipulation, improvements to mushroom fruiting, and synthetic biology applications for producing natural medicinal products. IMPORTANCETaiwanofungus camphoratus (Tc) is a basidiomycete fungus that causes brown heart rot of the aromatic tree Cinnamomum kanehirae. The Tc fruiting bodies have been used to treat hangovers, abdominal pain, diarrhea, hypertension, and other diseases first by aboriginal Taiwanese and later by people in many countries. To establish classical genetic and genomic approaches for this economically important medicinal mushroom, we first isolated and characterized four sexually competent monokaryons from two dikaryons wildly used for commercial production of Tc mushrooms. We applied PacBio single molecule, real-time sequencing technology to determine the near-completed genome sequences of four monokaryons. These telomere-to-telomere and gapless haploid genome sequences reveal all genomic variants needed to be studied and discovered, including centromeres, telomeres, retrotransposons, mating type loci, biosynthetic, and metabolic gene clusters. Substantial interspecies diversities are also discovered between Tc and several other mushroom model organisms, including Agrocybe aegerita, Coprinopsis cinerea, and Schizophyllum commune, and Ganoderma lucidum.

A Phase 3 clinical trial validating the potency and safety of an innovative, extra-long-acting interferon in chronic hepatitis C.

Background and Aim: Ropeginterferon alfa-2b is a novel mono-pegylated, extra-long-acting interferon. It is administered infrequently and showed good tolerability and clinical activity for the chronic hepatitis B or C treatment in our previous Phase 2 clinical trials. This study aims to validate the potency and safety of this novel agent in a Phase 3 chronic viral hepatitis setting. Methods: Patients with chronic hepatitis C genotype 2 were randomized to receive subcutaneous injections of ropeginterferon alfa-2b biweekly or the conventional pegylated interferon alfa-2b weekly for 24 weeks, combined with ribavirin. The primary endpoint was to assess the safety and antiviral potency of ropeginterferon alfa-2b by the non-inferiority in sustained virologic response at 12 weeks after treatment. Results: A total of 222 patients were enrolled. Ropeginterferon alfa-2b group showed a favorable safety profile. Side effects that were generally associated with prior interferon therapies, including neutropenia, asthenia, fatigue, alopecia, dizziness, decreased appetite, nausea, flu-like symptoms including myalgia, pyrexia, and headache, and administration site reactions, were notably less in the ropeginterferon alfa-2b group. The cumulative incidence of adverse events of special interest was also notably higher in the control group. The primary endpoint was met and ropeginterferon alfa-2b showed a better SVR12 rate of 79.8% than 71.9% of the control group. Conclusion: Ropeginterferon alfa-2b is efficacious and has a favorable safety profile as compared with the conventional pegylated interferon alfa-2b. This study together with previous Phase 2 data validated ropeginterferon alfa-2b to be a new treatment option for chronic hepatitis C genotype 2.