Maintenance PARP inhibitor (olaparib or niraparib) treatment is commonly prescribed following carboplatin/paclitaxel chemotherapy in ovarian cancer patients, but response is compromised by adaptive drug resistance [1]. We have shown that P-gp/ABCB1 influences resistance to paclitaxel and olaparib, but similar niraparib resistance mechanisms have not been described [2, 3]. We used qRT-PCR, Western blot, RNASeq and LC-MS/MS proteomics analysis to compare drug transporter expression in sensitive and resistant immortalised and primary patient-derived cell lines. ABCB1 and ABCG2 expression was modified by shRNA-mediated knockdown and heterologous expression, with chemosensitivity changes assessed by MTT and clonogenic assays. Substrate specificity of P-gp and BCRP was assessed by efflux assays in polarised cells. P-gp/ABCB1 expression was not increased in A2780nirapR cells, which alternatively up-regulated BCRP/ABCG2. ABCG2 was consistently induced in niraparib-resistant patients, but ABCB1 only in patients pre-treated with paclitaxel. shABCG2 re-sensitised A2780nirapR cells, while heterologous expression in A2780 cells induced drug resistance. Efflux assays confirmed that olaparib and niraparib are both P-gp and BCRP substrates, suggesting that resistance results from transcriptional regulation of efflux transporters not substrate specificity. Treatment-induced BCRP/ABCG2 induction is a novel clinically relevant niraparib resistance biomarker. Routine inclusion of paclitaxel in first-line chemotherapy regimens may promote efflux transporter-mediated resistance, compromising response to PARPi maintenance treatment.

Fungal ribosomally synthesized and post-translationally modified peptides (F-RiPPs): Biosynthesis, genome mining, structural diversity, and translational potential as targeted anticancer ADC payloads.

In recent years, nutrition and health have become topics of widespread societal concern, and galactooligosaccharides (GOS) have garnered significant interest as prebiotics. Composed of one to nine galactose units terminated by a glucose molecule, GOS exhibit remarkable thermostability, high water solubility, strong humectancy, and low caloric value. They provide various physiological benefits, including prebiotic activity, gut health maintenance, antibacterial, antiadhesive, and anti-inflammatory effects, as well as systemic regulation of blood sugar, lipids, immune homeostasis, and metabolic diseases. These properties support broad applications in the food industry, breeding field, material science, and medical science. Enzymatic production using β-galactosidases is the primary industrial method for GOS synthesis. This review provides an overview of recent advances in β-galactosidase biochemistry, crystal structures, catalytic mechanisms, molecular modification, immobilization, and heterologous expression, along with GOS physiological functions, production, applications, and whey utilization. Future opportunities for GOS research and development are also briefly discussed.

Comprehensive whole-genome analysis of the HD-Zip gene family in Rubus chingii and its functional characterization in prickle development.

Synergistic effect of chaperone-guided folding and energy allocation for enhancing 5-aminolevulinic acid in engineered Escherichia coli.

Metabolic engineering Corynebacterium glutamicum for efficient production of gastrodin.

Nematode-trapping fungi such as Arthrobotrys flagrans employ sophisticated strategies to immobilize and digest their prey. A critical, yet poorly understood, step in this interaction is the induction of prey paralysis following capture. Here, we characterize putative effector D (PefD), a small secreted protein from A. flagrans. We demonstrate that pefD expression is specifically upregulated during the early and middle stages of infection of Caenorhabditis elegans (12-24 h post inoculation) and PefD localizes to the infection bulb within the nematode. Deletion of pefD significantly delayed the paralysis of C. elegans, whereas its overexpression accelerated the process. Through heterologous pan-neuronal expression in C. elegans, we show that PefD directly attenuates host locomotion and significantly enhances the activity of the sleep-promoting RIS interneuron. Unlike other effectors such as NipA or CyrA, PefD specifically modulates neuronal activity patterns without inducing general neurodegeneration. Our results identify PefD as a key virulence factor that hijacks the endogenous sleep induction circuitry of the host to facilitate rapid prey immobilization.

Identification and functional analysis of GbMYB15 as a negative regulator in flavonoid biosynthesis of Ginkgo biloba.

How to successfully express insect microsomal P450 using a baculovirus system.

Heterologous expression of fungal glycoside hydrolase family 115 α-glucuronidases.

Enhancement of very-long-chain cuticular wax biosynthesis triggered by water loss in response to pericarp senescence in litchi fruit

Double-edged sword: Aspergillus flavus as a threat to food safety and a resource for biotechnology.

Overcoming hydrophobicity-driven aggregation: An integrated expression strategy enables high-yield soluble production of recalcitrant starch synthases in Escherichia coli.

Grapholita molesta V-ATPase D acts as a susceptibility determinant of larvae to Bt Cry2Ab toxin.

Estrogen-related receptor γ (ERRγ) is an orphan nuclear receptor whose molecular functions in transcriptional regulation remain incompletely understood. The androgen receptor (AR) is a ligand-dependent transcription factor that plays a pivotal role in prostate cancer by regulating gene expression through androgen-response elements. Its activity is tightly controlled by receptor conformation and coactivator recruitment. Although ERRγ has been implicated in the suppression of prostate cancer progression, whether it modulates AR signaling remains unclear. In this study, we examined the functional and molecular interplay between ERRγ and AR using a heterologous expression system in HeLa cells. We found that ERRγ suppresses AR-mediated transcriptional activation in a dose-dependent manner on ARE-containing promoters. Mechanistically, ERRγ interacted with ligand-activated AR in the nucleus and disrupted the intramolecular interaction between the N-terminal domain (NTD) and the C-terminal ligand-binding domain (LBD), which is required for full receptor activation. This interference did not affect AR nuclear translocation. Furthermore, ERRγ functionally competed with major transcriptional coactivators, including steroid receptor coactivators-3 (SRC-3) and p300, thereby attenuating coactivator-enhanced AR-dependent transcription. Collectively, these findings demonstrate that ERRγ functions as a novel corepressor of AR by destabilizing receptor conformation and blocking coactivator recruitment, providing new mechanistic insights into the regulation of AR-mediated transcription.

Colpoda are among the most predominant eukaryotic microorganisms in soil ecosystems, playing crucial roles in material and energy cycling within soil and plant rhizosphere environments. Colpoda can form two distinct types of cysts in soil: reproductive cysts and resting cysts. Reproductive cyst represents an essential developmental stage for Colpoda proliferation and environmental adaptation. This study comprehensively characterized the reproductive cyst formation process of Colpoda inflata, identifying carbohydrate-coated granular structures derived from bacterial digestive products as their key morphological feature. C. inflata secretions were found to stimulate reproductive cyst formation effectively. We obtained a high-quality genome assembly of C. inflata and subsequently isolated and characterized three classes of excretory proteins. In vitro experiments demonstrated that an alpha-amylase is sufficient to induce reproductive cyst formation and rapid proliferation in a dose-dependent manner, achieving maximum cell densities 4.6 times higher than those in standard culture conditions. Further investigations revealed that C. inflata alpha-amylase could cross-induce reproductive cyst formation in different Colpoda species, with induction efficiency inversely correlated with phylogenetic distance. Heterologous expression of alpha-amylases from various Colpoda species demonstrated cross-induction capabilities, suggesting interspecies interactions among Colpodas in soil and rhizosphere ecosystems. In summary, this study provides critical insights into the molecular mechanisms underlying Colpoda reproductive cyst formation. The identified mechanism enables substantial biomass enhancement of Colpoda populations, allowing for future genetic engineering applications that aim to develop Colpoda-based bioremediation strategies for soil contaminants and microbial interventions in agricultural production systems.

Directed evolution of a thermostable laccase from Geobacillus stearothermophilus for efficient reduction of oxygen.

Putative novel β-lactamase-encoding genes are increasingly identified in whole-genome sequencing (WGS) data, often without phenotypic or biochemical characterization. Here, we characterized the chromosome-encoded GUA-1 Ambler class A β-lactamase from the clinical isolate Pseudomonas guariconensis-like 65411. Among the 40 P. guariconensis genomes available in the GenBank database, only 8 carried a blaGUA-like gene, whereas the others encoded an AmpC β-lactamase, suggesting the existence of two distinct subspecies. Notably, these eight isolates, despite originating from diverse geographical regions, all harbored the blaGUA-like gene inserted at the same chromosomal locus. Heterologous expression in Pseudomonas aeruginosa and Escherichia coli revealed a clavulanic-acid-inhibited cefotaximase-type ESBL. GUA-1 shared 72% amino acid sequence identity with putative Ambler class A β-lactamases from Pseudomonas fulva, Pseudomonas mosselii, and Pseudomonas soli, and 57% with LUT-1, a class A cephalosporinase from Pseudomonas luteola. Kinetic analyses showed that GUA-1 hydrolyzed cefotaxime but not ceftazidime, similarly to LUT-1 and CTX-M-1-type ESBLs. IC50 measurements indicated strong inhibition by clavulanic acid, tazobactam, and avibactam, but not by vaborbactam. Molecular modeling supported these findings, showing favorable binding of cefotaxime in the active site, whereas steric hindrance from Trp274 and electrostatic repulsion from Asp240 likely prevent ceftazidime binding. The blaGUA-1 gene was chromosomally located, with no obvious promoter identified in the immediate upstream region. RT-PCR experiments revealed expression levels comparable to other β-lactamase genes present (blaDHA, blaCMY, blaOXA-1, and blaOXA-204) and to the upstream-located Na+/H antiporter gene. 5' RACE experiments suggested that the blaGUA-1 gene is co-transcribed along with the Na+/H gene. Overall, this study highlights the diversity of β-lactamases within Pseudomonas species.

Antimicrobial peptides (AMPs) are promising candidates for next-generation therapeutics due to their broad-spectrum activity and reduced propensity for resistance, making them valuable in medicine, agriculture, and biotechnology. However, traditional AMP production methods including isolation from natural sources and chemical synthesis are costly, inefficient, and environmentally unsustainable, particularly for longer or post-translationally modified peptides. While heterologous expression has emerged as a scalable and versatile alternative, its success depends strongly on host selection and tailored optimisation strategies. This review examines recent advances in fungal systems as platforms for AMP production. Fungal systems, and particularly yeasts such as Pichia pastoris, offer rapid growth, low-cost fermentation, secretion capacity, and the ability to perform key post-translational modifications (PTMs), making them leading hosts for recombinant AMPs. We outline strain choice and engineering strategies that enhance AMP yield and bioactivity, including promoter and codon optimisation, secretion signal choice, fusion partners, and the construction of tandem or chimeric AMPs. By integrating current methodologies and case studies, this review aims to guide future efforts toward efficient, scalable, and commercially viable AMP manufacturing in fungal hosts, positioning fungal biotechnology as a key enabler in the development of next-generation antimicrobial solutions.

Cyanobacteriochromes (CBCRs) are light-sensitive photoreceptors that regulate diverse cyanobacterial responses to light. In this study, we combined large-scale genome mining, phylogenetics, heterologous expression, structural modeling, and spectroscopy to identify and characterize a previously unrecognized family of CBCR photoreceptors. CBCRs are light-sensing proteins that bind a chromophore through a GAF (cGMP-specific phosphodiesterases, adenylyl cyclases, and the bacterial transcription factor FhlA) domain. This family is defined by a conserved N-terminal DUF4118 domain (Domain of Unknown Function 4118) and a DPCF (Asp-Pro-Cys-Phe) motif-containing GAF domain. Interestingly, these GAF domains are phylogenetically much closer to recently described DPCI-2 (Asp-Pro-Cys-Ile) GAF domains than to conventional DPCF (Asp-Pro-Cys-Phe) GAF domains, therefore named as DPCF-2 GAF domains. These proteins, primarily distributed within the Nostocales order, are consistently associated with conserved two-component signaling (TCS) elements, suggesting their integration into light-regulated signaling cascades that might coordinate transcriptional responses in filamentous cyanobacteria. Spectral characterization of the DPCF-2 GAF domain from Tolypothrix sp. PCC 7910 revealed a stable, fully reversible blue-teal photocycle, shifting from a blue-absorbing dark state (Pb, 417nm) to a teal-absorbing state (Pt, 514nm) upon blue light exposure. This distinctive spectral response opens new avenues for exploring both the biological functions of DPCF-2 CBCRs and their potential biotechnological applications.