We developed an experimental platform in which CFE continuously synthesizes MT-associated proteins directly within a dense MT network, enabling the active-matter constituents themselves, including motors, cross-linkers and regulatory proteins, to be produced during the experiment rather than prescribed at assembly (Fig. 1a). Guanosine-5′-(α,β-methyleno)triphosphate (GMPCPP)-stabilized MTs were combined with a CFE transcription-translation system and sedimented into a mechanically quiescent planar sheet within a 3.3 mm × 3.3 mm well (1.2 mm liquid column), open to air for oxygen availability11,23,27 (Supplementary Fig. 1). Monomeric kinesin motors were continuously expressed from a 3 nM T7-driven plasmid encoding a codon-optimized kinesin gene (Supplementary Table 1). To sustain long-term coupling between gene expression and active matter, the CFE reaction was optimized to promote depletion-mediated MT bundling and minimize competition between protein synthesis and motor activity over shared energetic resources (Methods). At early times, t < 2 h, when kinesin concentrations remained low, the MT sheet behaved as a passive, load-bearing material with negligible internal motion (Fig. 1b and Supplementary Video 1). At longer times, t > 2 h, kinesin accumulated and promoted the formation of multimeric clusters. The emergence of tetrameric clusters, the minimal motor assemblies capable of generating flow, enabled crosslinking and extensile sliding...

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by Jie Ran, Changfeng Wei, Yang Yang, Yufei Zhang, Guizhi Guo, Nan Ma, Long Yin, Hongjun Fan, Jingrui Li, Heng Guo, Renshuai Zhang, Runa Wang, Dengwen Li, Min Liu Primary cilia are essential microtubule-based sensory organelles, and their dysfunction has been increasingly linked to metabolic stress. However, the underlying molecular mechanisms remain poorly understood. Herein, we reveal that ciliary defects in retinal photoreceptors and renal tubules exacerbate tissue damage during the progression of diabetic complications. Under hyperglycemic stress, protein arginine methyltransferase 1 (PRMT1) and histone deacetylase 6 (HDAC6) are significantly upregulated in both retinal and renal tissues. Genetic ablation of either enzyme effectively preserves ciliary architecture and restores organ function in diabetic mice. Mechanistically, PRMT1 localizes to the basal body, where it interacts with and methylates HDAC6 at arginine 16, consequently enhancing HDAC6 stability. In turn, HDAC6 mediates the deacetylation of PRMT1 at lysine 128, which elevates PRMT1 protein levels. This mutual modification crosstalk establishes a pathological positive feedback loop that stabilizes a pro-disassembly complex at the basal body, thereby potentiating ciliary impairment and expediting the progression of diabetic complications. Pharmacological inhibition of the PRMT1-HDAC6 loop significantly attenuates the pathological features of both diabetic retinopathy and nephropathy. Collectively, our findings uncover a reciprocal regulatory mechanism mediated by deacetylation and arginine methylation that drives cilium disassembly under hyperglycemic stress, providing promising therapeutic targets for the treatment of metabolic ciliopathies.

by Jie Ran, Changfeng Wei, Yang Yang, Yufei Zhang, Guizhi Guo, Nan Ma, Long Yin, Hongjun Fan, Jingrui Li, Heng Guo, Renshuai Zhang, Runa Wang, Dengwen Li, Min Liu Primary cilia are essential microtubule-based sensory organelles, and their dysfunction has been increasingly linked to metabolic stress. However, the underlying molecular mechanisms remain poorly understood. Herein, we reveal that ciliary defects in retinal photoreceptors and renal tubules exacerbate tissue damage during the progression of diabetic complications. Under hyperglycemic stress, protein arginine methyltransferase 1 (PRMT1) and histone deacetylase 6 (HDAC6) are significantly upregulated in both retinal and renal tissues. Genetic ablation of either enzyme effectively preserves ciliary architecture and restores organ function in diabetic mice. Mechanistically, PRMT1 localizes to the basal body, where it interacts with and methylates HDAC6 at arginine 16, consequently enhancing HDAC6 stability. In turn, HDAC6 mediates the deacetylation of PRMT1 at lysine 128, which elevates PRMT1 protein levels. This mutual modification crosstalk establishes a pathological positive feedback loop that stabilizes a pro-disassembly complex at the basal body, thereby potentiating ciliary impairment and expediting the progression of diabetic complications. Pharmacological inhibition of the PRMT1-HDAC6 loop significantly attenuates the pathological features of both diabetic retinopathy and nephropathy. Collectively, our findings uncover a reciprocal regulatory mechanism mediated by deacetylation and arginine methylation that drives cilium disassembly under hyperglycemic stress, providing promising therapeutic targets for the treatment of metabolic ciliopathies.

by Jie Ran, Changfeng Wei, Yang Yang, Yufei Zhang, Guizhi Guo, Nan Ma, Long Yin, Hongjun Fan, Jingrui Li, Heng Guo, Renshuai Zhang, Runa Wang, Dengwen Li, Min Liu Primary cilia are essential microtubule-based sensory organelles, and their dysfunction has been increasingly linked to metabolic stress. However, the underlying molecular mechanisms remain poorly understood. Herein, we reveal that ciliary defects in retinal photoreceptors and renal tubules exacerbate tissue damage during the progression of diabetic complications. Under hyperglycemic stress, protein arginine methyltransferase 1 (PRMT1) and histone deacetylase 6 (HDAC6) are significantly upregulated in both retinal and renal tissues. Genetic ablation of either enzyme effectively preserves ciliary architecture and restores organ function in diabetic mice. Mechanistically, PRMT1 localizes to the basal body, where it interacts with and methylates HDAC6 at arginine 16, consequently enhancing HDAC6 stability. In turn, HDAC6 mediates the deacetylation of PRMT1 at lysine 128, which elevates PRMT1 protein levels. This mutual modification crosstalk establishes a pathological positive feedback loop that stabilizes a pro-disassembly complex at the basal body, thereby potentiating ciliary impairment and expediting the progression of diabetic complications. Pharmacological inhibition of the PRMT1-HDAC6 loop significantly attenuates the pathological features of both diabetic retinopathy and nephropathy. Collectively, our findings uncover a reciprocal regulatory mechanism mediated by deacetylation and arginine methylation that drives cilium disassembly under hyperglycemic stress, providing promising therapeutic targets for the treatment of metabolic ciliopathies.

Cilia and flagella are microtubule-based organelles found in a wide range of eukaryotic organisms that form cilia and flagella are assembled from basal bodies. In the malaria parasite, eight flagellated microgametes are assembled from 8 basal bodies that form de novo as a single group (not next to a parent basal body) in the cytoplasm of microgametocytes extremely rapidly, in as little 8 minutes but is not synchronised. The flagellated microgametes exit from a microgametocyte, each consisting of an axoneme and a haploid nucleus. Fertilisation occurs via a HAP2-mediated fusion with the macrogamete. Despite the essential role of microgametes in malaria transmission and being the only flagellated stage, little is known about the process of basal body formation, biogenesis at the ultrastructure level and their role in fertilisation. We used dual axis serial section electron tomography (ssET) to reveal the unusual single microtubule structure of the basal body and discovered an associated electron dense basal body granule. Using whole cell reconstructions of microgametocytes, free microgametes and macrogametes by serial block face scanning electron microscopy (SBF-SEM), we discovered a deuterosome-like structure only present during the initial formation of 8 basal bodies that could be a nucleating platform for de novo basal body formation. Finally, we reveal that entry of the microgamete into the macrogamete occurs via directed event at a single point of entry with the basal body and granule leading entry. These discoveries highlight the essential functions of basal bodies from initial microgamete assembly to male-female gamete fertilisation.

Cilia and flagella are microtubule-based organelles found in a wide range of eukaryotic organisms that form cilia and flagella are assembled from basal bodies. In the malaria parasite, eight flagellated microgametes are assembled from 8 basal bodies that form de novo as a single group (not next to a parent basal body) in the cytoplasm of microgametocytes extremely rapidly, in as little 8 minutes but is not synchronised. The flagellated microgametes exit from a microgametocyte, each consisting of an axoneme and a haploid nucleus. Fertilisation occurs via a HAP2-mediated fusion with the macrogamete. Despite the essential role of microgametes in malaria transmission and being the only flagellated stage, little is known about the process of basal body formation, biogenesis at the ultrastructure level and their role in fertilisation. We used dual axis serial section electron tomography (ssET) to reveal the unusual single microtubule structure of the basal body and discovered an associated electron dense basal body granule. Using whole cell reconstructions of microgametocytes, free microgametes and macrogametes by serial block face scanning electron microscopy (SBF-SEM), we discovered a deuterosome-like structure only present during the initial formation of 8 basal bodies that could be a nucleating platform for de novo basal body formation. Finally, we reveal that entry of the microgamete into the macrogamete occurs via directed event at a single point of entry with the basal body and granule leading entry. These discoveries highlight the essential functions of basal bodies from initial microgamete assembly to male-female gamete fertilisation.

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The cellular distribution of mitochondria in response to stress and local energy needs is governed by the relative activities of the microtubule-based molecular motors kinesin and dynein. The mechanis...

The cellular distribution of mitochondria in response to stress and local energy needs is governed by the relative activities of the microtubule-based molecular motors kinesin and dynein. The…

The cellular distribution of mitochondria in response to stress and local energy needs is governed by the relative activities of the microtubule-based molecular motors kinesin and dynein. The mechanis...

The cellular distribution of mitochondria in response to stress and local energy needs is governed by the relative activities of the microtubule-based molecular motors kinesin and dynein. The mechanis...

The cellular distribution of mitochondria in response to stress and local energy needs is governed by the relative activities of the microtubule-based molecular motors kinesin and dynein. The mechanis...