bims-toxgon 2026-03-29 papers

bims-toxgon

Biomed News

on Toxoplasma gondii metabolism

Issue of 2026–03–29
seventeen papers selected by
Lakesh Kumar, BITS Pilani

Identification of TgENT1 as the TgUUT1 Uracil/Uridine Transporter of Toxoplasma gondii.
Host-directed therapeutic strategies against apicomplexan parasites: targeting purinergic P2 receptors.
Sirtuin inhibition by plumbagin connects protein acetylation to cell division.
Histone deacetylases and cell cycle regulators orchestrate cell identity transitions during Arabidopsis root regeneration.
Bumped Kinase Inhibitor BKI-1708 Interferes in Cytokinesis and Drives Baryzoite Conversion in the Cyst-Forming Apicomplexan Parasites Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti.
Suppression of ITPK1 and IPMK activities impairs mTORC1 signaling in pancreatic β-cells and implicates IP 5 in stabilizing activated mTORC1.
All the Way: A Decade of SIRT1 in Breast Cancer.
The SIRT1-Mediated p53 Deacetylation Pathway Modulates Apoptosis and Promotes Viral Replication in MVC-Infected Cells.
Succinylation modification in diabetes and diabetic complications: Mechanisms and functions (Review).
Licochalcone A as a Potential Anti-Toxoplasma Agent: A Target Identification and Pharmacokinetic Study.
Toxoplasma gondii affects trait anxiety in adult ADHD.
The revised Cryptosporidium life cycle offers opportunities for fundamental and translational advances.
The Role of Protein Post-Translational Modifications in the Pathogenesis of Nephrolithiasis: Mechanistic Insights and Translational Potential.
Current Understanding of SIRT7 Function and Its Emerging Roles in the Central Nervous System.
A heterologous marker-free selection approach for CRISPR/Cas9-based gene editing in the malaria parasite Plasmodium falciparum.
Reversal of ATP synthase is a key attribute accompanying cellular differentiation of Trypanosoma brucei insect forms.
Multicomplex Integrative Structural Modeling of a Human Histone Deacetylase Interactome.

Pathogens. 2026 Mar 02. pii: 266. [Epub ahead of print]15(3):

Identification of TgENT1 as the TgUUT1 Uracil/Uridine Transporter of Toxoplasma gondii.

Hamza A A Elati, Mariana Ferreira Silva, Lilach Sheiner, Harry P de Koning.

  The protozoan pathogen Toxoplasma gondii is responsible for toxoplasmosis, a disease that can be deadly in immunocompromised patients and the developing fetus during pregnancy. Current treatments are widely considered to be suboptimal. We have recently reported that 5-fluoropyrimidines have highly promising anti-toxoplasmosis effects and are internalized by the parasite by a high-affinity uracil/uridine transporter, TgUUT1. Here, we attempt to identify the gene encoding this transport protein. The only nucleoside or nucleobase family identified in the T. gondii genome was the Equilibrative Nucleoside Transporter (ENT) family, with four members. Of these, TgAT1 is known to be purine-specific, and deletion of the TgENT2 and TgENT3 genes, either separately or jointly, did not affect uridine transport or sensitivity to 5-fluoropyrimidines. In contrast, depletion of TgENT1, an essential gene, resulted in a significant reduction in the uptake of both uracil and uridine but not of the amino acid tryptophan. Moreover, expression of TgENT1 in a Leishmania mexicana cell line with low endogenous uracil uptake rates significantly increased uracil uptake for these cells. We conclude that it is highly probable that TgENT1 encodes the T. gondii uracil/uridine transporter. On the basis of our previous results, we infer that TgENT1 likely also mediates the uptake of 5-fluoropyrimidines.

Keywords:  5-fluorouracil; Toxoplasma gondii; nucleoside transporter; pyrimidine antimetabolite; uridine transport

DOI:  https://doi.org/10.3390/pathogens15030266
Purinergic Signal. 2026 Mar 21. pii: 30. [Epub ahead of print]22(2):

Host-directed therapeutic strategies against apicomplexan parasites: targeting purinergic P2 receptors.

Mariana M Chaves, Nayara Carvalho-Barbosa, Luiz Eduardo Baggio Savio, Robson Coutinho-Silva.

  Apicomplexan parasites establish intracellular infections that profoundly alter host cell physiology and elicit complex immune responses. The long-standing coevolution between these parasites and vertebrate hosts has resulted in extensive overlap between parasite and host metabolic pathways, limiting the feasibility of conventional parasite-centered therapeutic approaches. Increasing evidence indicates that host-derived signals generated during infection play a decisive role in shaping parasite survival and dissemination. Among these signals, extracellular nucleotides released in response to cellular stress and tissue damage have emerged as key modulators of innate immune responses. These molecules are sensed by purinergic P2 receptors, which integrate danger signals with inflammatory and microbicidal pathways. This review examines how purinergic signaling contributes to host-parasite interactions during apicomplexan infections, with particular emphasis on Toxoplasma gondii and Plasmodium spp. We discuss the dual role of P2 receptors in coordinating immune responses and directly affecting parasite viability, highlighting their potential as targets for host-directed therapeutic strategies.

Keywords:  Apicomplexan parasites; Malaria; P2 receptors; Therapeutic targets; Toxoplasmosis

DOI:  https://doi.org/10.1007/s11302-026-10145-7
J Cell Sci. 2026 Mar 25. pii: jcs.264052. [Epub ahead of print]

Sirtuin inhibition by plumbagin connects protein acetylation to cell division.

Valentina Sirri, Antoine Vidal, Pascal Roussel.

  Naphthoquinones interfere with biological systems and exhibit pharmaceutical properties. As an electrophile, naphthoquinone plumbagin may react with nucleophiles, mainly thiols, and forms covalent adducts. Here, we further characterized the plumbagin effects in HeLa cells. First, we have demonstrated that plumbagin interferes with mitosis by affecting the mitotic spindle formation without preventing exit from mitosis. This plumbagin-induced delay in cell division was reproduced by class III histone deacetylase (HDAC) inhibitors but not by the class I, II and IV pan-HDAC inhibitor TSA, and therefore, most likely involved sirtuins. Second, we have established that in addition to blocking cell division, plumbagin induces protein hyperacetylation in a sulfhydryl arylation-dependent manner. Finally, in a manner consistent with the plumbagin-dependent inhibition of sirtuin 2 (SIRT2), we show that plumbagin interferes with the centrosomal localization of SIRT2 and induces increased acetylation of the SIRT2 target, α-tubulin. Inhibition of sirtuin activity induces hyperacetylation of proteins such as TPX2 and its delocalization, and consequently interferes with mitotic spindle formation and cell division. Since plumbagin most likely inhibits SIRT2, which is known to modulate several proteins involved in different pathological processes, we propose that it could be a promising therapeutic agent.

Keywords:  Cell cycle; HDAC; Mitotic spindle; Naphthoquinone; Sirtuin

DOI:  https://doi.org/10.1242/jcs.264052
Mol Plant. 2026 Mar 25. pii: S1674-2052(26)00083-3. [Epub ahead of print]

Histone deacetylases and cell cycle regulators orchestrate cell identity transitions during Arabidopsis root regeneration.

Ramin Rahni, Laura R Lee, Graeme Vissers, Indie Suresh, Brandon M Gorodokin, Pui-Leng Ip, Bruno Guillotin, Kenneth D Birnbaum.

  The widespread regenerative capacity of plants is mediated by the ability of specialized cells to reprogram their fate, but the sequential cellular states of regenerating plant cells remain an open question. Here, we characterize the trajectory of cellular reprogramming using single-cell RNA/ATAC-seq, imaging, and mutant analysis. The earliest events were dependent on repressive chromatin modification, where Multiome and genetic analysis showed that Class I histone deacetylases (HDACs) HDA9 and HDA19 were needed to shut down old identities and to prevent a runaway stress response. Cell division mediates a second step needed for the acquisition of many new identity markers, where division rates were tuned by DOF transcription factor OBP1 accelerating and SMR5, 7, and 10 decelerating division rates hours later. The results show how plants actively mediate the loss of remnant identities within hours of injury and then tune cell division rates to rapidly reprogram cells to new identities.

Keywords:  Cell Cycle; Chromatin; HDACs; Regeneration; Reprogramming; Root Development

DOI:  https://doi.org/10.1016/j.molp.2026.03.013
Int J Mol Sci. 2026 Mar 23. pii: 2914. [Epub ahead of print]27(6):

Bumped Kinase Inhibitor BKI-1708 Interferes in Cytokinesis and Drives Baryzoite Conversion in the Cyst-Forming Apicomplexan Parasites Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti.

Maria Cristina Ferreira de Sousa, Joachim Müller, Kai Pascal Alexander Hänggeli, Manfred Heller, Anne-Christine Uldry, Sophie Braga-Lagache, Alexandre Leitao, Luis-Miguel Ortega-Mora, Kayode K Ojo, Wesley C Van Voorhis, Andrew Hemphill.

  Bumped kinase inhibitors (BKIs) have demonstrated safety and promising efficacy against various apicomplexan pathogens both in vitro and in vivo, but do not act parasiticidal in vitro. In the closely related cyst-forming coccidians Toxoplasma gondii, Neospora caninum and Besnoitia besnoiti, treatments with BKI-1708 induce the conversion of intracellular tachyzoites into atypical multinucleated complexes named "baryzoites". In this study, we comparatively assessed tachyzoites and baryzoites of all three species with respect to ultrastructure, differential antigen expression by immunofluorescence, and overall differential protein expression by MS-proteomics. TEM demonstrated common, but also distinguishing, structural features in baryzoites of the three species. They contained newly formed zoites, unable to complete cytokinesis, and thus they were trapped intracellularly. An electron-dense cyst wall-like structure was found only in T. gondii baryzoites. Species-specific differences in antigen expression were observed by immunofluorescence. Comparative proteomic analysis of baryzoites versus tachyzoites revealed a downregulation of ribosomal proteins, proteins associated with secretory organelles, as well as of transcription and translation factors in baryzoites across all species. Bradyzoite-specific markers were upregulated only in T. gondii baryzoites. Two alveolin-domain filament proteins and a hypothetical protein (TGME49_236950, NCLIV_050850, BESB_060040) were detected at higher abundance in all three species. Thus, baryzoites exhibit distinct phenotypic and proteomic profiles, with ambiguous expression of tachyzoite and bradyzoite antigens, suggesting a reversible response to stress rather than progression into a fully differentiated form.

Keywords:  apicomplexan parasites; baryzoites; bumped kinase inhibitor; calcium dependent protein kinase; coccidia; mitogen activated protein kinase-like 1; multinucleated complexes; proteomics

DOI:  https://doi.org/10.3390/ijms27062914
bioRxiv. 2026 Mar 07. pii: 2026.03.04.709646. [Epub ahead of print]

Suppression of ITPK1 and IPMK activities impairs mTORC1 signaling in pancreatic β-cells and implicates IP 5 in stabilizing activated mTORC1.

Clarisse Iradukunda, Edward A Salter, Dilipkumar Uredi, Xiaodong Wang, Andrzej Wierzbicki, Lucia E Rameh.

mTORC1 integrates growth factor and nutrient signals to regulate cellular metabolism, yet there are no metabolites known to directly regulate mTORC1 activity in cells. Cryo-EM studies revealed that inositol hexakisphosphate (IP 6 ) associates with the FAT domain of mTOR, suggesting that inositol phosphates may directly modulate mTOR activity. We previously showed that higher-order inositol phosphates enhance mTORC1 kinase activity and stability in vitro. Here, we investigated whether inositol phosphate metabolism regulates mTORC1 signaling in pancreatic β-cells. Suppression or acute inhibition of inositol phosphate multikinase (IPMK), as well as knockdown of inositol trisphosphate kinase 1 (ITPK1), selectively reduced cellular IP 5 levels without altering IP 6 and resulted in impaired basal and insulin-stimulated mTORC1 signaling, particularly under physiological glucose and low growth factor conditions. Combined inhibition of IPMK and ITPK1 nearly abolished IP 5 and reduced IP 6 , demonstrating that these enzymes compensate to supply IP 5 for IP 6 synthesis. Importantly, depletion of IP 5 did not impair PI3K/Akt activation but accelerated termination of the mTORC1 signal, indicating a role for IP 5 in stabilizing the active mTORC1 complex. Reduction of inositol phosphate levels did not prevent insulin- or glucose-induced mTORC1 activation, revealing that IP 5 primarily regulates signal persistence rather than initiation. Together, these findings identify IP 5 as a metabolic regulator that prolong mTORC1 activity in β-cells, providing a mechanism by which cellular metabolic state modulates sustained mTORC1 signaling.
Significance Statement: mTORC1 is a central metabolic regulator whose chronic activation contributes to metabolic disease, yet mechanisms that sustain mTORC1 activity after its activation are poorly understood. We show that enzymes controlling inositol phosphate metabolism regulate the stability of mTORC1 signaling in pancreatic β-cells by maintaining cellular levels of inositol pentakisphosphate (IP 5 ). Reducing IP 5 impairs basal and sustained mTORC1 signaling without affecting upstream growth factor or energy-sensing pathways, revealing a mechanism that controls signal duration rather than activation. These findings identify IP 5 as a metabolic regulator of mTORC1 and suggest that targeting inositol phosphate metabolism may provide a strategy to modulate mTORC1 activity in metabolic disease.

DOI: https://doi.org/10.64898/2026.03.04.709646
Biomedicines. 2026 Mar 15. pii: 671. [Epub ahead of print]14(3):

All the Way: A Decade of SIRT1 in Breast Cancer.

Giovanni Pratelli, Mauro Montalbano, Federica Affranchi, Chiara Occhipinti, Marianna Lauricella, Daniela Carlisi, Anna De Blasio.

  Breast cancer (BC) is a highly heterogeneous genetic disease, comprising several subtypes with distinct features that significantly influence prognosis and treatment outcomes. Among these subtypes, triple-negative breast cancer (TNBC) is particularly aggressive and makes it resistant to many standard therapies. Epigenetic mechanisms, including acetylation and deacetylation, are crucial in regulating gene expression and maintaining normal cellular functions and are closely associated with BC progression. In this context, the histone deacetylases sirtuins (SIRT1-7) regulate key biological processes like genomic stability, inflammation, cellular senescence, and metabolic functions, increasingly linked to cancer. In particular, SIRT1 shows dual roles, functioning both as a tumor suppressor or an oncogene, contributing to cancer initiation, progression, and metastasis as well as chemotherapy resistance. Despite extensive research in the past decade, the exact role of SIRT1 in BC, especially in TNBC, remains controversial. Recent findings suggest that SIRT1 can be modulated not only through pharmacological approaches but also using natural extracts, offering potential alternative or complementary therapeutic strategies. Additionally, SIRT1 activity is regulated by a complex network of miRNAs, highlighting the need for further investigation. This review aims to summarize recent studies to identify key insights into the role of SIRT1 and explore it as a potential therapeutic target in BC.

Keywords:  SIRT1; SIRT1 modulators; breast cancer; miRNAs; triple-negative breast cancer

DOI:  https://doi.org/10.3390/biomedicines14030671
Pathogens. 2026 Feb 25. pii: 242. [Epub ahead of print]15(3):

The SIRT1-Mediated p53 Deacetylation Pathway Modulates Apoptosis and Promotes Viral Replication in MVC-Infected Cells.

Yan Yan, Xiang Ren, Yishu Xiao, Fang Li, Jianhui Guo, Kai Ji, Zhiping Hei, Zhijie Zhang, Yuning Sun.

  Minute virus of canines (MVC) is an autonomous canine parvovirus that causes severe pathological outcomes, including embryo mortality, spontaneous abortion, and congenital malformations in neonatal puppies. Although MVC infection has been shown to induce host cell cycle arrest and apoptosis, the underlying regulatory mechanisms that coordinate cell proliferation and control apoptotic responses during viral replication remain poorly understood. Sirtuin 1 (SIRT1) is an NAD+-dependent deacetylase that plays a critical role in regulating cell cycle progression, DNA damage responses, and apoptosis. However, its involvement in MVC infection has not been fully elucidated. Herein, we show that MVC infection markedly upregulates the mRNA and protein expression levels of SIRT1 in a time-dependent manner. MVC infection activates the SIRT1-p53 signaling axis and modulates the acetylation status of p53. In addition, MVC alters the subcellular distribution of SIRT1, promoting its nuclear translocation and colocalization with the viral protein VP2. Functional analyses demonstrated that pharmacological activation of SIRT1 enhanced the viability of MVC-infected WRD cells (virus-tropic cell), promoting viral replication, prolonging S-phase arrest, and reducing apoptosis. Conversely, inhibition of SIRT1 produced the opposite effects, which were closely associated with regulation of the SIRT1-p53 signaling axis. Moreover, SIRT1 knockdown accelerated apoptosis and attenuated S-phase arrest, whereas SIRT1 overexpression further strengthened S-phase retention. Collectively, our findings identify the SIRT1-p53 signaling axis as an important regulator of cell cycle progression and apoptosis during MVC infection, highlighting SIRT1 as a key host factor that supports viral replication and persistence and a potential target for antiviral intervention.

Keywords:  MVC; SIRT1; apoptosis; p53 deacetylation; viral replication

DOI:  https://doi.org/10.3390/pathogens15030242
Mol Med Rep. 2026 May;pii: 149. [Epub ahead of print]33(5):

Succinylation modification in diabetes and diabetic complications: Mechanisms and functions (Review).

Yeteng Xiong, Fei Luo, Bingnan Li, Qinfeng Yang.

  Despite adequate glycaemic control, diabetic complications frequently progress, underscoring how persistently protein post‑translational modifications (PTMs) contribute to disease pathology by sustaining 'metabolic memory'. Lysine succinylation, a PTM derived from the tricarboxylic acid cycle intermediate succinyl‑CoA and primarily regulated by the desuccinylase sirtuin 5 (SIRT5), has emerged as a key metabolic modulator. By introducing a marked shift in lysine charge, succinylation can notably influence enzyme activity and protein stability. The present review integrates current evidence associating the disruption of the succinyl‑CoA/SIRT5 regulatory axis with impaired metabolic flexibility in diabetes. The mechanisms by which pathological hypersuccinylation compromises mitochondrial bioenergetics, particularly by inhibiting uncoupling protein 1 in obesity and the pyruvate dehydrogenase complex in diabetic cardiomyopathy, are described, and its implications in neurodegeneration within diabetic retinopathy through modification of optineurin are elucidated. The present review also discusses the mechanistic role of epigenetic dysregulation, highlighting how activation of the lysine acetyltransferase 2A/H3K79 succinylation/spermidine/spermine N1‑acetyltransferase family member 2 pathway promotes ferroptosis and inflammation in diabetic kidney disease. The context‑dependent duality of SIRT5 function is also examined; although key in limiting lipotoxicity in cardiomyocytes and podocytes, SIRT5 can paradoxically aggravate glomerular fibrosis in renal mesangial cells by suppressing p53 signalling. The present findings suggested that re‑establishing succinylation homeostasis represents not simply a metabolic correction but a strategic therapeutic objective. However, given the tissue‑specific and frequently opposing effects of SIRT5, future therapeutic approaches should aim to emphasize organ‑targeted delivery rather than systemic modulation to minimize off‑target toxicity while effectively addressing diabetic complications.

Keywords:  diabetes; diabetic cardiomyopathy; diabetic kidney disease; diabetic retinopathy; obesity; succinylation

DOI:  https://doi.org/10.3892/mmr.2026.13859
Biomolecules. 2026 Mar 10. pii: 410. [Epub ahead of print]16(3):

Licochalcone A as a Potential Anti-Toxoplasma Agent: A Target Identification and Pharmacokinetic Study.

Bing Li, Zexin Tao, Yichen Jing, Yubin Bai, Weiwei Wang, Bintao Zhai, A M Abd El-Aty, Chao Zhang, Jiyu Zhang, Fangdi Hu.

  Toxoplasmosis is a zoonotic disease with limited therapeutic options, which are further hampered by significant toxicity and suboptimal efficacy. Effective interventions for chronic infection remain insufficient, and thus, natural product-derived drug screening remains a key focus in anti-Toxoplasma research. Licochalcone A (Lico A), a major bioactive compound isolated from Glycyrrhiza uralensis, exhibits potent activity against Toxoplasma tachyzoites. However, systematic studies of its targets, pharmacokinetics, and efficacy are lacking, hindering its development as an anti-Toxoplasma candidate drug. In this study, we used SPR-MS to identify 33 high-affinity target proteins (affinity score > 1000). Furthermore, an AI-driven multidimensional analysis identified a cluster of five proteins (TgMORN1, D3XD37, ABCB2, MIC15, and IDH), with TgMORN1 yielding the highest composite score. RNAi experiments confirmed TgMORN1 as a key target, as its silencing attenuated the anti-proliferative effect of Lico A. Western blotting, NanoDSF, and SPR supported direct binding between Lico A and TgMORN1, suggesting that Lico A modulates TgMORN1 thermal stability through residues S168 and D203, with high species specificity. Pharmacokinetic evaluation revealed that Lico A had favorable absorption and blood-brain barrier permeability, supporting its potential utility in treating brain disease. In vitro assays showed that Lico A effectively inhibited Toxoplasma gondii brain cyst formation. Collectively, these findings support Lico A as a promising candidate for the treatment of toxoplasmosis.

Keywords:  AI; SPR; TgMORN1; Toxoplasma gondii; licochalcone A; pharmacokinetic

DOI:  https://doi.org/10.3390/biom16030410
Front Psychiatry. 2026 ;17 1766562

Toxoplasma gondii affects trait anxiety in adult ADHD.

Alexandra P Lam, Angelika Carl, Klaus P Kohse, Alexandra Philipsen.

   Background/objective: Growing evidence emerges that Toxoplasma gondii (T. gondii) is associated with mental disorders like anxiety disorders or attention-deficit/hyperactivity disorder (ADHD). In ADHD patients around 25% suffer from comorbid anxiety disorders. As the impact of a latent T. gondii infection on anxiety in adult ADHD remains unknown, this study aims to investigate this relationship.
Methods: In a case-control study, including 140 participants, venous blood samples were taken of 70 adult ADHD patients and 70 controls for serological analysis of markers of infection and inflammation (leukocytes, C-reactive protein, anti-T. gondii immunoglobulin M (IgM) and anti-T. gondii immunoglobulin G (IgG) (seropositivity), IgG titers (serointensity) as well as anti-T. gondii IgG avidity. The influences on state and trait anxiety were explored using the State-Trait-Anxiety Inventory (STAI).
Results: Seropositivity was significantly associated with the leukocyte count in all participants (n = 140, p = 0.004). Moreover, regression analysis revealed a significant association of seropositivity and serointensity with trait anxiety but not with state anxiety: trait anxiety was significantly lower in seropositive ADHD patients compared to seronegative subjects with ADHD (n = 70, p=0.029). In addition, trait anxiety scores decreased in an IgG-dependent manner in all participants (n = 140, p = 0.028) as well as in the ADHD group (n = 70, p = 0.015). Comorbid anxiety disorders in ADHD were not associated with latent T. gondii infection.
Conclusion: Our data is the first revealing an association between T. gondii and trait anxiety in a serointensity-dependent manner in individuals with ADHD. Further research is needed to clarify the clinical impact of the observed lower trait anxiety in individuals with ADHD and latent T. gondii infection.

Keywords:  ADHD; Toxoplasma gondii; anxiety disorders; state anxiety; state-trait-anxiety inventory; trait anxiety

DOI:  https://doi.org/10.3389/fpsyt.2026.1766562
Trends Parasitol. 2026 Mar 26. pii: S1471-4922(26)00047-4. [Epub ahead of print]

The revised Cryptosporidium life cycle offers opportunities for fundamental and translational advances.

Aurélia C Balestra, Abigail M Daniels, Boris Striepen.

  Cryptosporidium is a leading cause of severe diarrheal disease, for which effective treatments and vaccines are lacking. The past decade has seen breakthrough advances in how the parasite and disease can be studied in the field and the laboratory. This has led to an increasingly molecular understanding of how parasite protein secretion orchestrates invasion and host-parasite interactions and to a revision of the Cryptosporidium life cycle. Parasite sex emerges as an engine of genomic innovation, allowing the parasite to adaptively evolve host specificity, virulence, and drug resistance. The unique importance of sex for Cryptosporidium also offers opportunities for forward genetic discovery and could provide new targets for treatment and prevention. Here, we review key concepts and discuss the outstanding questions critical to fundamental understanding and translational advancement.

Keywords:  Cryptosporidium; cryptosporidiosis; genetic cross; host–parasite interaction; life cycle; parasite sex

DOI:  https://doi.org/10.1016/j.pt.2026.02.011
Cells. 2026 Mar 19. pii: 554. [Epub ahead of print]15(6):

The Role of Protein Post-Translational Modifications in the Pathogenesis of Nephrolithiasis: Mechanistic Insights and Translational Potential.

Wenlong Wan, Baokang Wang, Junyi Yang, Yang Xun, Xiao Yu.

  Nephrolithiasis is a prevalent urological disorder worldwide, whose pathogenesis involves a complex network of crystal formation, cellular injury, and microenvironmental dysregulation. As a critical mechanism for regulating cellular functions, protein post-translational modifications (PTMs) have been increasingly implicated in multiple facets of kidney stone formation, including crystal-cell interactions, oxidative stress responses, and inflammatory signaling pathways. This review systematically synthesizes the biochemical foundations of PTMs, the molecular microenvironment of nephrolithiasis, and the roles of key modifications such as phosphorylation and acetylation in the pathogenesis of calculi. It further explores the translational potential of PTM detection technologies in clinical practice. Current evidence indicates that PTMs influence the nucleation, growth, and aggregation of crystals by modulating the activity of pro-/anti-lithogenic proteins, the expression of cell adhesion molecules, and inflammatory pathways. Consequently, therapeutic strategies targeting PTMs may offer novel avenues for the prevention and management of kidney stones. Future research should focus on integrating multi-omics approaches with functional validation to elucidate the dynamic regulatory networks of PTMs within the stone microenvironment, thereby advancing the development of precision medicine.

Keywords:  acetylation; crystal-cell interactions; nephrolithiasis; phosphorylation; protein post-translational modifications

DOI:  https://doi.org/10.3390/cells15060554
Cells. 2026 Mar 19. pii: 548. [Epub ahead of print]15(6):

Current Understanding of SIRT7 Function and Its Emerging Roles in the Central Nervous System.

Yuchen Jiao, Chuangui Wang, Shengping Zhang.

  SIRT7is an NAD+-dependent deacetylase predominantly localized in the nucleolus, where it plays important roles in chromatin regulation, transcriptional control, and cellular stress response. Accumulating evidence has revealed that SIRT7 participates in multiple molecular processes, including ribosomal RNA transcription, histone modification, DNA damage repair, metabolic regulation, and inflammatory signaling pathways. Through these mechanisms, SIRT7 contributes to the pathogenesis of various human diseases, particularly cancer and metabolic disorders. In recent years, emerging studies have begun to uncover the roles of SIRT7 in the central nervous system (CNS). Although research in this area remains limited, available evidence suggests that SIRT7 may be involved in neuronal homeostasis, glial function, neuroinflammation, and responses to brain injury. Furthermore, dysregulation of SIRT7 has been implicated in CNS-related pathologies. In this review, we summarize the understanding of SIRT7 molecular mechanisms and its implications in human disease, with special emphasis on its emerging roles in the CNS. We also address unresolved questions and propose future research directions to facilitate a deeper understanding of SIRT7 in neurological physiology and pathology.

Keywords:  SIRT7; deacetylase; post-translational modification

DOI:  https://doi.org/10.3390/cells15060548
mSphere. 2026 Mar 26. e0088425

A heterologous marker-free selection approach for CRISPR/Cas9-based gene editing in the malaria parasite Plasmodium falciparum.

Eilidh Carrington, Daniel Ballmer, Igor Niederwieser, Basil T Thommen, Nicolas M B Brancucci, Till S Voss.

  CRISPR/Cas9-based gene editing of the malaria parasite Plasmodium falciparum has emerged as a transformative tool for advancing functional studies on parasite biology and identifying new therapeutic targets. Currently applied CRISPR/Cas9 methodologies depend on a limited set of heterologous drug resistance markers for the selection of transgenic parasites, which restricts the potential for iterative genetic modifications. Here, we developed a heterologous marker-free CRISPR/Cas9 gene editing strategy (CRISPR/Cas9pyrR) for P. falciparum based on the simultaneous editing of a gene of interest and introduction of pyrimethamine (PYR) resistance-conferring mutations into the dihydrofolate reductase-thymidylate synthase (pfdhfr-ts) gene. By providing a pfdhfrpyrR donor sequence and the Cas9 expression cassette on separate plasmids, CRISPR/Cas9pyrR ensures that only parasites acquiring both plasmids survive under PYR pressure. As a proof of principle, we applied CRISPR/Cas9pyrR to generate two transgenic parasite lines expressing GFP-tagged versions of the putative nuclear envelope protein PfGEX1 and nuclear pore protein PfNUP116, respectively. We show that PfGEX1-GFP marks the nuclear envelope specifically in gametocytes, but not in asexual blood stage parasites. Similarly, and against previous reports, we find PfNUP116-GFP expression is undetectable in asexual parasites but instead localizes to a distinct perinuclear region in early gametocytes. These results suggest dynamic compositional changes of the nuclear periphery during sexual differentiation. We further demonstrate sequential genetic engineering of the PfNUP116-GFP-expressing line using the human dhfr drug resistance marker combined with WR99210-based selection by additionally tagging PfAP2-G, the master transcriptional regulator of sexual commitment, and the nuclear pore protein PfNUP313. Hence, CRISPR/Cas9pyrR provides a versatile and effective new method that enhances and complements the current genetic toolkit for malaria research.IMPORTANCEMalaria tropica, which is caused by the unicellular parasite Plasmodium falciparum, is one of the most devastating infectious diseases worldwide. The development of urgently needed effective vaccines and new antimalarial drugs with novel modes of action requires a profound understanding of parasite biology. CRISPR/Cas9-based genome engineering is beyond doubt the most important experimental approach to study the function and essentiality of parasite proteins and to identify and validate new vaccine and drug targets. In this study, we developed and successfully applied a modified CRISPR/Cas9 strategy, termed CRISPR/Cas9pyrR, that avoids the use of a heterologous drug resistance marker for the selection of genetically modified parasites. CRISPR/Cas9pyrR thus complements the CRISPR/Cas9 toolbox available for gene editing in P. falciparum and overcomes some of the limitations of currently employed protocols.

Keywords:  CRISPR/Cas9; Plasmodium falciparum; malaria

DOI:  https://doi.org/10.1128/msphere.00884-25
Commun Biol. 2026 Mar 27.

Reversal of ATP synthase is a key attribute accompanying cellular differentiation of Trypanosoma brucei insect forms.

Michaela Kunzová, Eva Doleželová, Martin Moos, Brian Panicucci, Alena Zíková.

The mitochondrial FoF1-ATP synthase is a reversible nanomachine that normally produces ATP via oxidative phosphorylation but under stress conditions it can reverse to maintain the mitochondrial membrane potential at the expense of ATP, a process regulated by the conserved inhibitory factor 1 (IF1). We show that ATP synthase reversal also occurs during in vitro-induced differentiation of the unicellular parasite Trypanosoma brucei, partially mirroring events in the tsetse fly. Differentiation of insect forms is marked by increased expression of alternative oxidase and reduced levels of trypanosomal IF1 (TbIF1), changes that may promote ATP synthase reversal. Parasites lacking TbIF1 efficiently progressed to the mammalian-infective form, coinciding with increased ATP synthase reversal, a higher ADP/ATP ratio, elevated phosphorylation of AMP-activated protein kinase (AMPK), enhanced proline-supported respiration, and increased mitochondrial and cellular reactive oxygen species (ROS). In contrast, inducible TbIF1 overexpression diminished these hallmarks and locked parasites in the initial insect stage. Our findings reveal that TbIF1 downregulation enables life cycle progression and underscore a regulatory role for the ATP synthase-IF1 axis.

DOI: https://doi.org/10.1038/s42003-026-09933-z
bioRxiv. 2026 Mar 17. pii: 2026.03.16.712198. [Epub ahead of print]

Multicomplex Integrative Structural Modeling of a Human Histone Deacetylase Interactome.

Jules Nde, Kartik Majila, Rosalyn C Zimmermann, Cassandra Kempf, Ying Zhang, Joseph Cesare, Janet L Thornton, Jerry L Workman, Laurence Florens, Shruthi Viswanath, Michael P Washburn.

Histone Deacetylase (HDAC) 1 and 2 are key enzymatic components in multiple large chromatin remodeling complexes including NuRD, SIN3, and CoREST. In addition, both HDAC 1 and 2 contain a large intrinsically disordered region (IDR) within their C-terminal domain (CTD). How HDAC1/2 assemble into these complexes and the structure of the CTD IDR remains poorly understood. Here, we used HDAC1/2 to isolate their protein interaction networks from cells and used crosslinking mass spectrometry (XL-MS) coupled with the Integrative Modeling Platform to build structural models of the NuRD, SIN3A, and CoREST complexes. Next, we implemented an AlphaFold-enabled XL-MS constrained modeling approach to investigate how HDAC1 could assemble into these complexes. We show that the CTD IDR of HDAC1 folds into alpha helices in these complexes. Finally, we built a complete integrative structural model of a NuRD subcomplex including the abundant HDAC1:MBD3:MTA1:GATAD2B:RBBP4 subunits, which included 6 IDRs. The approaches used herein are broadly applicable for the study of protein complexes and protein interaction networks that can provide important insights into IDRs.

DOI: https://doi.org/10.64898/2026.03.16.712198