bims-placeb 2026-05-10 papers

bims-placeb

Biomed News

on Placental cell biology

Issue of 2026–05–10
fourteen papers selected by
Carlos M Guardia, National Institute of Environmental Health Sciences

Deciphering the Maternal Uterine Signals that Shape Placenta Development.
Developmental landmarks and cellular transitions during extravillous trophoblast cell differentiation.
Copper Deficiency Disrupts Placental Development and Lipid Metabolism, Contributing to Fetal Growth Restriction†.
Immunoregulation and cellular crosstalk in uterine spiral artery remodeling during human pregnancy.
Image-informed modelling of microscale exchange in the human placenta.
Placental insulin-mTOR and stress-inflammatory signaling patterns are associated with childhood adiposity.
Fatty acid transporters in the porcine conceptus and early placenta and the effects of polyunsaturated fatty acids on trophoblast cells.
Cross-species insights into placental evolution and diseases at the single-cell resolution.
HIF1-α induces mitochondrial fission in trophoblastic cells during early pregnancy and in preeclampsia.
The dynamic expression pattern of signaling pathways involved in early embryo development.
Comparative single-cell analysis of black rockfish (Sebastes schlegelii) ovarian stroma reveals placenta-like adaptations toward viviparity.
PFAS Exposure Perturbs Lipid Metabolism to Promote Gestational Diabetes Mellitus and Alter Growth Trajectories via Distinct Mechanisms in Singletons and Twins.
pH-mediated activation of the lysosomal arginine sensor SLC38A9.
Ghosts on the Membrane: Cytoskeletal Pinning Influences Nanoscale Cell Membrane Organization.

Reproduction. 2026 May 06. pii: xaag053. [Epub ahead of print]

Deciphering the Maternal Uterine Signals that Shape Placenta Development.

Jacob R Beal, Purba Mukherjee, Indrani C Bagchi, Milan K Bagchi.

  In humans and rodents, proper formation of a hemochorial placenta is essential for a successful pregnancy, as the placenta serves as the maternal-fetal interface that facilitates the exchange of nutrients, gases, and waste between the mother and the developing fetus. The fetal compartment of the placenta is formed by extraembryonic trophoblast cells that proliferate and differentiate into distinct lineages that play specialized roles during placental development. Trophoblast lineage development and function are highly dependent upon embryonic paracrine signaling and timely activation of transcription factors within the trophoblasts. However, recent studies have increasingly emphasized the critical role of maternal factors in regulating trophoblast differentiation and placental development. Notably, conditional knockout mouse models have demonstrated the essential contribution of maternal decidual expression of specific molecular signals in orchestrating these processes. In this review, we summarize the role of maternal uterine signals in shaping placental development. We examine the role of decidua-derived secreted factors in directing trophoblast lineage specification and promoting appropriate levels of trophoblast invasion. Additionally, we explore the crosstalk between maternal and fetal-derived signals that collectively regulate the extent and timing of trophoblast invasion into the uterine tissue. The interplay between maternal immune cells and trophoblasts is also discussed, with a focus on mechanisms that not only support immune tolerance to the semi-allogeneic placenta but also mediate trophoblast invasion and vascular remodeling. Finally, we consider the clinical implications of maternal influences on placentation, including the emerging potential of decidual extracellular vesicles as non-invasive biomarkers for pregnancy health and placental dysfunction.

Keywords:  Endometrium; Implantation; Placenta; Trophoblast; Uterus

DOI:  https://doi.org/10.1093/reprod/xaag053
Proc Natl Acad Sci U S A. 2026 May 12. 123(19): e2529836123

Developmental landmarks and cellular transitions during extravillous trophoblast cell differentiation.

Ayelen Moreno-Irusta, Malay Kumar Basu, Esteban M Dominguez, Thomas S Chen, Sawyer H Smith, Kaela M Varberg, Hiroaki Okae, Takahiro Arima, Michael J Soares.

  Human trophoblast stem (TS) can be captured, maintained in vitro under specific conditions, and differentiated into extravillous trophoblast (EVT) cells. The regulatory mechanisms that govern the self-renewal and differentiation of human TS cells into EVT cells are largely unknown. In this study, bulk RNA-sequencing (RNA-seq) and single cell RNA-seq (scRNA-seq) were performed on human TS cells maintained in the stem state and on cells progressing from the stem state into EVT cells (differentiation days 3, 6, and 8). Distinct bulk and single cell transcript profiles were identified for each day of analysis. Day 3 of EVT cell differentiation represented a striking transition point and was readily distinguished from stem state and days 6 and 8 of EVT cell differentiation. Analysis of scRNA-seq led to the identification of several unique cell populations, trophoblast cell developmental state-specific regulons, and trajectories. We elucidated functional roles of key regulators of EVT cell development: cyclin B1, CCAAT/enhancer-binding protein beta, and A Disintegrin And Metalloproteinase (ADAM) metallopeptidase with thrombospondin type 1 motif 20. Collectively, we have defined developmental landmarks and transitional cell populations during EVT cell differentiation. These findings provide a valuable resource and foundation for future investigations into regulatory mechanisms controlling TS cell differentiation into the EVT cell lineage.

Keywords:  differentiation; extravillous trophoblast cells; maternal–fetal interface; placenta; trophoblast stem cells

DOI:  https://doi.org/10.1073/pnas.2529836123
Biol Reprod. 2026 May 07. pii: ioag096. [Epub ahead of print]

Copper Deficiency Disrupts Placental Development and Lipid Metabolism, Contributing to Fetal Growth Restriction†.

Yu-Jie Ran, Ya-Qi Wang, Jia-Qi Xu, Li Luo, Jing-Tang, Ying-Lin Dong, En-Xiang Chen, Fang-Fang Li, Ling-Ling Ruan, Li-Juan Fu, You-Long Xie, Yu-Bin Ding.

  To investigate how copper deficiency during pregnancy affects placental structure, metabolism, and trophoblast function, contributing to fetal growth restriction (FGR). Pregnant C57BL/6N mice were treated with ammonium tetrathiomolybdate (ATTM) to induce copper deficiency, with two different dosages (30 and 60 mg·kg-1·d-1) administered daily from gestational day 1 to day 14. On day 15, assessments were made on fetal growth, placental development, and spatial metabolomics. In parallel, trophoblast cells (HTR8/SVneo) were subjected to copper chelation or SLC31A1 knockdown to model copper deficiency in vitro. Cell invasiveness and proliferation were evaluated using appropriate assays, along with the measurement of molecular markers to assess the impact of copper deficiency. Copper deficiency significantly reduced maternal serum copper levels, leading to FGR, as evidenced by shorter crown-rump lengths, lower fetal weights, and altered fetal-to-placental weight ratios. Structural abnormalities in the placental junctional zone, including reduced size and altered morphology, were observed. Metabolomic analysis revealed disrupted lipid metabolism, with alterations in glycerophospholipids and fatty acids, and lipid droplet accumulation. Copper deficiency impaired trophoblast migration and invasion, linked to decreased MMP2 and MMP9 expression in vivo and in vitro. In vitro studies also showed altered lipid metabolism in SLC31A1-knockdown trophoblast cells. Copper deficiency disrupts placental structure and lipid metabolism, impairs trophoblast function, and contributes to FGR, highlighting the critical role of copper in fetal development and maternal health.

Keywords:  cell invasion; copper deficiency; fetal growth restriction; lipid metabolism; placenta

DOI:  https://doi.org/10.1093/biolre/ioag096
J Reprod Immunol. 2026 May 02. pii: S0165-0378(26)00076-8. [Epub ahead of print]175 104907

Immunoregulation and cellular crosstalk in uterine spiral artery remodeling during human pregnancy.

Yeling Ma, Xiao Fang, Shuo Wang, Xin Yu, Yan-Ling Wang, Xuan Shao.

  Uterine spiral artery (SA) remodeling is essential in human pregnancy to ensure adequate blood perfusion to the maternal-fetal interface and meet the growing demands of the developing fetus. Accumulating evidence underscores the critical role of immunoregulation in this process. In this article, we systematically summarize current advances in this field and propose a compartmentalized framework distinguishing two functionally integrated niches: the intravascular space where endovascular extravillous trophoblasts (enEVTs) interact with maternal immune cells within remodeling SAs, and the perivascular niche where decidual immune cells direct SA remodeling from outside the vessels. By examining the cellular crosstalk among trophoblasts, decidual immune cells, endothelial cells, and vascular smooth muscle cells within and between these niches, we present an integrated model explaining how immune tolerance and vascular transformation are spatiotemporally coordinated. Dysregulation of these finely tuned processes is linked to major pregnancy disorders, highlighting new avenues for pathophysiological research and the development of targeted diagnostic and therapeutic strategies.

Keywords:  Decidual immune cells; Immunoregulation; Trophoblast; Uterine Spiral artery remodeling

DOI:  https://doi.org/10.1016/j.jri.2026.104907
Placenta. 2026 May 04. pii: S0143-4004(26)00157-8. [Epub ahead of print]

Image-informed modelling of microscale exchange in the human placenta.

Eleanor Doman, Richard Mcnair, Carl A Whitfield, Megan Sharps, Oliver E Jensen, Adam Stevens, Rohan M Lewis, Igor L Chernyavsky, Bram Sengers.

  The human placenta supports fetal development by mediating the exchange of gases, nutrients, drugs, and waste across a highly heterogeneous microscale interface formed by terminal villi. While placental transport has long been studied using simplified multiscale models, progress has been constrained by limited access to realistic microstructure geometries, uncertainty in barrier composition, and difficulties linking local geometries to organ-level measurements. Here, we review recent advances in placental imaging and mathematical modelling that are enabling better characterisation of microscale exchange. We outline how multimodal structural imaging, including X-ray phase-contrast approaches, microCT, optical microscopy and volume electron microscopy, can quantify villous and vascular architecture across scales. We discuss modelling frameworks informed by these data, including descriptions of maternal and fetal haemodynamics, image-based exchange-capacity concepts, and compartmental approaches that incorporate delivery limitations. We also discuss recent advances in the understanding of transporter-mediated transfer, and the emerging role of spatial 'omics in parametrising membrane function and regional heterogeneity. We conclude by identifying likely next steps and ways forward for image-based models of exchange in the human placenta.

Keywords:  Mathematical modelling; Microscale imaging; Placental transfer; Spatial transcriptomics

DOI:  https://doi.org/10.1016/j.placenta.2026.04.027
BMC Med. 2026 May 08.

Placental insulin-mTOR and stress-inflammatory signaling patterns are associated with childhood adiposity.

Ellen C Francis, Kristen E Boyle, Lauren E Gyllenhammer, Dana Dabelea, Thomas Jansson, Wei Perng.

   BACKGROUND: Placental signaling pathways regulate nutrient transport and fetal growth, with potential long-term consequences for offspring metabolic health. Most prior human studies have focused on individual placental markers, limiting insight into the role of coordinated activity across multiple pathways in relation to offspring outcomes. Our objective was to identify patterns across placental nutrient signaling pathways and assess whether the latent placental signaling patterns were associated with early childhood adiposity, and secondarily, explore associations of adiposity-associated patterns with metabolic biomarkers.
METHODS: Among 108 mother-child pairs from the Healthy Start cohort, we quantified 33 placental signaling proteins and their phosphorylated-to-total protein ratios involved in nutrient sensing, insulin/growth factor signaling, stress/inflammation, and mitochondrial biogenesis using Simple Western assays of term placental villus tissue. We applied unsupervised methods to identify latent patterns and LASSO regression was used to select patterns associated with %fat mass at age 4. Multivariable linear regression was used to estimate associations adjusting for offspring age, sex, and maternal pre-pregnancy BMI. These same models were used in exploratory analysis of fasting levels of adiponectin, leptin, insulin, glucose, and lipids at age 4.
RESULTS: We identified two placental signaling patterns associated with %fat mass. The insulin-mTOR-energy sensing pattern was associated with lower childhood %fat mass (β = -2.46, 95% CI - 4.84, - 0.09) and adiponectin, and the stress-inflammatory MAPK pattern was associated with higher %fat mass (β = 1.28, 95% CI 0.05, 2.51), leptin, and triglycerides; however, the FDR p-values ranged from 0.06 to 0.13.
CONCLUSION: Two placental signaling patterns were associated with childhood %fat mass and metabolic markers. These findings indicate that capturing placental activity across several signaling pathways may yield insights into early origins of adiposity and metabolic health.

Keywords:  cardiometabolic health; fetal programming; insulin signaling; maternal-fetal exchange; nutrient sensing; placenta; pregnancy; unsupervised analysis

DOI:  https://doi.org/10.1186/s12916-026-04896-8
Sci Rep. 2026 May 02.

Fatty acid transporters in the porcine conceptus and early placenta and the effects of polyunsaturated fatty acids on trophoblast cells.

Agnieszka Blitek, Magdalena Szymanska.

  This study aimed to determine whether fatty acids (FAs) may affect the function of the early porcine placenta. First, the expression of FA transporters (CD36, SLC27A) in conceptuses and placentae of days 10-11, 12-13, 15-16, 18-20, 25, and 30 pregnant gilts (n = 5-8 per group) was examined using Real-time PCR, Western blot, and immunohistochemistry. Then, primary trophoblast (pTr) cells from days 15-16 conceptuses were exposed to n-6 and n-3 polyunsaturated FAs (PUFAs) to study prostaglandin (PG) synthesis and the expression of genes related to FA action, angiogenesis, steroidogenesis, and lipid transport. Furthermore, pTr cell proliferation and adhesion in response to PUFAs were determined colorimetrically. Increased mRNA expression of CD36, SLC27A1, and SLC27A2 was detected in days 18-25 placentae compared with days 10-13 conceptuses. SLC27A4 and SLC27A6 expression was greater in days 10-11 spherical than in days 15-16 elongated conceptuses. SLC27A1, SLC27A4, and SLC27A6 were localized at the placenta-endometrium interface. PUFAs of n-6 series elevated PGE2 and PGI2 synthesis, whereas n-3 PUFAs stimulated PGE2 but inhibited PGI2 output. All PUFAs up-regulated the mRNA expression of CPT1A, a rate-limiting enzyme of FA β-oxidation. Moreover, docosahexaenoic acid (DHA) increased FABP5, SLC27A4, LDLR (lipoprotein receptor), and proangiogenic ANGPT1 and ANGPTL4 mRNA expression. DHA and arachidonic acid stimulated pTr cell proliferation, while linoleic and eicosapentaenoic acids increased cell adhesion. These results are the first demonstrating dynamic changes of FA transporter expression in peri-implantation conceptuses and developing placentae of the pig and indicate FA uptake by the early placenta. Furthermore, PUFAs may support placenta development by modulating gene expression, increasing PGE2 level, and promoting trophoblast cell viability and adhesion.

Keywords:  Fatty acid transporters; Pig; Placenta development; Polyunsaturated fatty acids; Pregnancy; Trophoblast cells

DOI:  https://doi.org/10.1038/s41598-026-51024-w
Nat Commun. 2026 May 09.

Cross-species insights into placental evolution and diseases at the single-cell resolution.

Guanghui Tan, Ao Zhang, Xuesha Cao, Jingyu Yang, Youjie Cui, Fei Wang, Tao Shi, Hengkuan Li, Haoping Wang, Huiquan Shan, Jilong Ren, Yaqi Zhou, Menghan Wang, Funong Luo, Xi Guo, Wuqiang Huo, Yingran Liu, Zhannur Niyazbekova, Xihong Wang, Zhenyu Xiao, Yi Zheng, Yu Jiang.

The placenta is essential for fetal development, yet its molecular evolution across mammals remains elusive. Here, we present a comprehensive single-cell transcriptomic atlas of ~300,000 cells from ten species representing the four primary placental types: discoid, cotyledonary, diffuse, and zonary. Our cross-species analysis identifies trophoblast lineages as the primary drivers of placental diversification. By reconstructing differentiation trajectories, we elucidate the regulatory networks shaping trophoblast development across diverse architectures. We propose that the unique gene expression profile of human trophoblasts underlies the susceptibility to preeclampsia and miscarriage. Functional experiments demonstrate that TGIF1 acts as a key upstream regulator of extravillous trophoblast growth and migration. TGIF1 and its targets, including ADAM12, WNT3A, and ZNF831, are associated with preeclampsia and pregnancy loss. Collectively, this high-resolution framework provides fundamental insights into the molecular evolution of the placenta and its contribution to reproductive success and diseases.

DOI: https://doi.org/10.1038/s41467-026-72652-w
iScience. 2026 May 15. 29(5): 115674

HIF1-α induces mitochondrial fission in trophoblastic cells during early pregnancy and in preeclampsia.

Léa Poinsignon, Audrey Chissey, Juliette Colombel, Bertrand Lefrère, Charlotte Izabelle, Lucie Bernard, Jean-Louis Beaudeux, Thierry Fournier, Ioana Ferecatu, Isabelle Hernandez, Amal Zerrad-Saadi.

  The placenta undergoes a major oxygen transition between 7 and 9 gestation weeks (GW) and 12-14 GW. Inadequate adaptation to these environmental changes leads to oxidative stress and the release of syncytial knots, a hallmark of preeclampsia (PE). As mitochondria play a central role in redox regulation, we investigated mitochondrial network dynamics and the role of hypoxia-inducible factor 1-alpha (HIF1-α) in trophoblasts during early pregnancy and in PE. HIF1-α is stabilized in placenta before 9 GW, associated with mitochondrial hypertubulation and increased mitofusin (MFN) 1 expression. Experimental stabilization of HIF1-α using cobalt chloride induces mitochondrial fission through downregulation of MFN1 and MFN2, and upregulation of dynamin-related protein 1 (DRP1). In pre-eclamptic placentas, significantly elevated mitochondrial fission 1 protein (FIS1) levels suggest enhanced mitochondrial fission, supporting FIS1 as a potential biomarker of PE-associated placental alterations.

Keywords:  cell biology; developmental biology

DOI:  https://doi.org/10.1016/j.isci.2026.115674
Cell Commun Signal. 2026 May 07.

The dynamic expression pattern of signaling pathways involved in early embryo development.

Zifan Song, Shi Song, Nan Wang, Xiaomeng Wang, Liying Yan, Jie Qiao, Peng Yuan.

  Early embryonic development in mammals involves extensive intercellular communication and interaction. The rapidly changing signaling pathways, governed by signaling pathway-related genes (SPGs), underlie these intricate communication networks and mediate a series of developmental events, including blastulation and gastrulation. However, the detailed expression patterns of SPGs remain to be clearly illustrated. In this study, we used mouse and human transcriptomic and epigenomic data to systematically depict the dynamics of signaling pathway networks during early embryonic development. Our results indicate that zygotic genome activation (ZGA) triggers considerable remodeling of SPGs transcriptional patterns, which coincides with noticeably elevated promoter accessibility after ZGA in both humans and mice. In addition, most SPGs are maternally inherited and are more conserved between humans and mice compared to those activated by the zygotic genome. Interestingly, we found that various extracellular matrix (ECM)-related signaling pathways were highly enriched during early embryogenesis. Two enriched and conserved receptors in several ECM-related pathways, SDC1 and SDC4, were expressed on the cell membrane from oocyte to blastocyst stage both in humans and mice. Knockdown of Sdc1 and Sdc4 in mice resulted in an impaired developmental rate from the 8-cell stage via different mechanisms. Collectively, our study provides new insights into understanding the underlying mechanisms of early embryo development.

Keywords:  Cell-cell interaction; Early embryo development; Extracellular matrix; Multi-omics; Signaling pathway

DOI:  https://doi.org/10.1186/s12964-026-02909-w
Commun Biol. 2026 May 04.

Comparative single-cell analysis of black rockfish (Sebastes schlegelii) ovarian stroma reveals placenta-like adaptations toward viviparity.

Xinlin Yang, Jianshuang Li, Bingyan Zheng, Chong Zhang, Haishen Wen, Yun Li, Xin Qi.

The black rockfish (Sebastes schlegelii) is a viviparous teleost with high fecundity and prolonged female sperm storage for about six months despite lacking a specialized storage organ. During gestation, its ovarian stroma undergoes a functional shift from supporting oocyte growth to maintaining embryo development, resembling the maternal decidua in mammals. Here, we present a single-cell atlas of the ovarian stroma across unfertilized, normal-gestation, and abnormal-gestation states. Cross-species integration with human and mouse datasets reveals convergence on decidualization-like programs during early pregnancy, while highlighting lineage-specific implementation by distinct cell types. We further implicate annexins in ovarian sperm storage and show that abnormal-gestation is associated with lymphatic endothelial skewing and lipid-handling signatures, consistent with stromal lipid recapture. Together, these findings provide a framework for the maternal contribution to teleost placentation and reveal convergent, placenta-like adaptations underlying viviparity.

DOI: https://doi.org/10.1038/s42003-026-10195-y
Environ Sci Technol. 2026 May 03.

PFAS Exposure Perturbs Lipid Metabolism to Promote Gestational Diabetes Mellitus and Alter Growth Trajectories via Distinct Mechanisms in Singletons and Twins.

Chunqing Lu, Wen Wang, Zhao Li, Anen He, Shuo Zhang, Lingmin Hu, Lu Bai, Juan Li, Juan Wen, Yawei Wang, Guibin Jiang.

  Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that cross the placenta, posing a potential threat to maternal and fetal health. However, epidemiological evidence linking PFAS exposure to gestational diabetes mellitus (GDM) remains limited, almost exclusively to singleton pregnancies, with mechanistic understanding notably lacking. In this nested case-control study, we integrated exposomic and metabolomic analyses of serum from 462 singleton and 84 twin pregnancies, quantifying 48 PFAS alongside lipid metabolites. PFAS exposure was positively associated with GDM risk, with distinct congener profiles observed between singletons and twins. In mixture analyses, the association was stronger in twins, and PFOA and PFNA emerged as the primary risk contributors for singletons and twins, respectively. Mechanistically, PFAS perturbed lipid metabolism and increased GDM risk through pregnancy-type-specific pathways. In singletons, lipid mediators were linked to branched-chain amino acid and eicosanoid metabolism pathways, whereas in twins, bile acid metabolism emerged as a potentially predominant pathway. Maternal diet significantly shaped this environmental risk, revealing a key exposure-lifestyle interaction. Importantly, maternal PFAS exposure and GDM status together influenced offspring growth trajectories up to age 4, indicating potential long-term developmental consequences. We provide the first evidence that PFAS exposure induces pregnancy-type-specific metabolic disruptions, establishing a novel mechanistic link to GDM and highlighting its public health implications.

Keywords:  gestational diabetes mellitus (GDM); growth trajectory; lipid metabolomics; per- and polyfluoroalkyl substances (PFAS); twin pregnancy

DOI:  https://doi.org/10.1021/acs.est.6c01759
FEBS Lett. 2026 May 03.

pH-mediated activation of the lysosomal arginine sensor SLC38A9.

Xuelang Mu, Ampon Sae Her, Tamir Gonen.

  Cells rely on metabolic control; the mechanistic target of rapamycin complex 1 (mTORC1) senses nutrient availability, particularly amino acids. Lysosomes maintain amino acid homeostasis through recycling. SLC38A9, a lysosomal amino acid transporter, functions as a critical sensor in the mTORC1 pathway. Here, we investigate how pH regulates SLC38A9 activity. We show that arginine uptake is pH-dependent, with His544 residue serving as the pH sensor. Mutating His544 abolishes pH dependence without impairing overall transport, indicating His544 influences transport through protonation/deprotonation, instead of involving in the substrate binding. We propose a working model for pH-induced activation, through comparing two determined SLC38A9 structures at different pH. These findings reveal how local ionic shifts regulate lysosomal transporters and fine-tune SLC38A9 function to control mTORC1 signaling.

Keywords:  SLC family; amino acid transport; mTOR complex; pH‐regulation; transceptor

DOI:  https://doi.org/10.1002/1873-3468.70352
Biomolecules. 2026 Apr 17. pii: 596. [Epub ahead of print]16(4):

Ghosts on the Membrane: Cytoskeletal Pinning Influences Nanoscale Cell Membrane Organization.

Shambhavi Pandey, Thorsten Wohland.

  The lateral organization of the plasma membrane (PM) is vital for cellular signaling, yet the specific mechanisms by which the internal cortical actin meshwork templates the organization of the external lipid leaflet remain poorly understood. While established models like the 'picket-fence' emphasize physical barriers to diffusion, recent observations of fiber-like "ghost" structures in the distribution of glycosylphosphatidylinositol-anchored proteins (GPI-APs) suggest a more intricate mode of spatial coordination. In this study, we utilize imaging total internal reflection fluorescence correlation spectroscopy (ITIR-FCS) and variable-angle TIRF to resolve whether these filamentous patterns represent genuine membrane-proximal features or optical artifacts of cytosolic transport. Our results demonstrate that these fiber-like tracks are strictly confined to the immediate PM interface and disappear as the evanescent field probes deeper into the cytosol. While the spatial distribution of GPI-APs is templated by the underlying actin meshwork, quantitative diffusion mapping shows that the lateral dynamics of the probe remains largely uniform and is not significantly modulated by these filamentous patterns. By pharmacologically perturbing the actin scaffold and membrane cholesterol, we show that this transbilayer coupling is contingent upon a cholesterol-dependent cytoskeletal pinning mechanism. These findings demonstrate a decoupling of spatial organization and molecular dynamics, providing evidence for how the actin scaffold patterns nanoscale membrane organization without imposing long-range barriers to diffusion.

Keywords:  GPI-anchored proteins; ITIR-FCS; cholesterol; cortical actin; cytoskeletal pinning; membrane topography; plasma membrane; transbilayer coupling

DOI:  https://doi.org/10.3390/biom16040596