sem micrographs  (JEOL)

Journal: RSC Advances

Article Title: Application of in-line imaging technology in preparation of Ziegler–Natta catalysts for propylene polymerization

doi: 10.1039/d6ra02038k

Figure Lengend Snippet: SEM micrographs of Cat1 particles collected at magnification 500× (a), 2000× (b), 10 000× (c) and 50 000× (d).

Article Snippet: The micrographs were collected on a SU8600 (HITACHI).

Techniques:

Journal: bioRxiv

Article Title: The HSP90–CDC37 Chaperone System Orchestrates RAF1 Kinase Activation Through a Pre-Dimerization Mechanism

doi: 10.64898/2026.03.25.713956

Figure Lengend Snippet: (A) Schematic diagram showing the domain organization of the proteins present in the RRHCC complex. The dashed and non-colored sections indicate regions where there is no interpretable density. (B) Cryo-EM map of the RRHCC complex (RRHCC_a6) at 2.6 Å global resolution. The map is colored according to each subunit as in (A). (C) Cartoon representation of the RRHCC assembly in complex with ATP (sphere representation). The N-lobe sections of RAF1.1 and RAF1.2 associated with HSP90-CDC37 are depicted as thicker coils. The black oval highlights the interaction of RAF1.2 N-lobe with CDC37.1-MD and HSP90-A. (D) Zoom of the N-lobe of RAF1.2 showing an almost completely folded αC helix, which is captured between the CTD of HSP90-A and CDC37.1-MD. (E) Two perpendicular views of the interface formed by the RAF1.2 αC helix, CDC37.1-MD, and HSP90-A (green, orange, and blue, respectively) in the local map RRHCC_Cloc. Key interacting residues are labeled. The accompanying cartoon of αC in the mold illustrates the arrangement. The residues at the base of the αC helix set its position and register by engaging distinct hydrophobic (hp), basic, and acidic patches. (F) Surface representation of CDC37.1-MD (model from RRHCC_Cloc map), colored by electrostatic potential. Two opposite views are shown: CDC37.1-MD region (upper panel) and the corresponding HSP90-A interface (lower panel). RAF1.2 (green ribbon) fits into the central groove of CDC37.1 MD, which features two oppositely charged patches at its exit (upper panel). RAF1.2 residue H402 inserts into a pocket of HSP90-A (lower panel). A fully extended αC helix from the folded RAF1 structure (PDB: 8CPD, transparent grey) would clash with the acidic patch of CDC37.1-MD. Relevant RAF1.2 residues are labeled. (G) Same as in (F) with the αC of RAF1.2 displayed with its electrostatic potential surface, showing its complementation with the electrostatic potential of CDC37 and HSP90. Pairs of interacting residues between CDC37.1-MD and HSP90-A are indicated. (H) The αC helix of RAF1.2 is substituted with its fully folded conformation from PDB entry 8CPD to illustrate that the folded helix is incompatible with the acidic patch located at the exit of CDC37.1-MD. (I) Electrostatic potential surface of the folded RAF1 N-lobe, with the αC helix shown as a grey ribbon. For comparison, the fitted RAF1.2 model from the RRHCC_Cloc map is displayed in green in the same orientation as in (A). (J) Interface between the RAF1 N-lobes in a dimer (PDB:8CPD), with residues that contact CDC37-MD highlighted. One subunit is colored according to the scheme used in . (K) Schematic illustrating how the secondary structure elements of the RAF1 N-lobe assemble into the final folded state. When the αC helix is released from the CDC37-MD, the segment of RAF1 that is clamped by HSP90 must be released upon HSP90 opening. Then, together with the final 30 N-terminal residues in the RRHCC, the kinase can fold the final two β-sheets. These β-sheets are inserted between the αC helix and the remaining β-strands building the RAF1 N-lobe. (L) Comparison of the model from the local map and the folded RAF1 N-lobe (PDB: 8CPD), aligned at the αC helix region. The inset shows the fully folded RAF1 structure, with the N-lobe in grey and the C-lobe in white. Also see Figure S2, SI1-4, and Table S2.

Article Snippet: Cryo-EM data and processing workflow, related to , , 3, 4, Table S2. (A) Representative motion-corrected cryo-EM micrograph of the RHC particles in vitreous ice imaged with a Titan Krios Falcon 4i direct detector camera (-2.3 μm defocus). (B) Characteristic reference-free 2D averages of the RHC particles.

Techniques: Cryo-EM Sample Prep, Labeling, Residue, Comparison

Journal: bioRxiv

Article Title: The HSP90–CDC37 Chaperone System Orchestrates RAF1 Kinase Activation Through a Pre-Dimerization Mechanism

doi: 10.64898/2026.03.25.713956

Figure Lengend Snippet: Composition of the HSP90 ATP-binding sites in the different cryo-EM maps (see also SI4). Each panel shows the density for a given site as a transparent surface, together with the modeled ligands at that site (phosphate is labeled as PO4). The central schematic summarizes the ATP-hydrolysis trajectory along the RHC and RRHCC assemblies, starting from an open HSP90 dimer. The upper branch corresponds to the RHC pathway, and the lower branch to the RRHCC classes. Blue arrows indicate increased HSP90 ATPase activity, red arrows indicate decreased activity, and dashed lines denote alternative transitions between the RHC and RRHCC pathways.

Article Snippet: Cryo-EM data and processing workflow, related to , , 3, 4, Table S2. (A) Representative motion-corrected cryo-EM micrograph of the RHC particles in vitreous ice imaged with a Titan Krios Falcon 4i direct detector camera (-2.3 μm defocus). (B) Characteristic reference-free 2D averages of the RHC particles.

Techniques: Binding Assay, Cryo-EM Sample Prep, Labeling, Activity Assay

Journal: bioRxiv

Article Title: The HSP90–CDC37 Chaperone System Orchestrates RAF1 Kinase Activation Through a Pre-Dimerization Mechanism

doi: 10.64898/2026.03.25.713956

Figure Lengend Snippet: (A) Two views of the cryo-EM density map of class RHCp23_c with the domain organization of p23. (B) Ribbon representation of RHCp23_c in two orientations matching (a). (C) Cryo-EM map of class RHCp23_p. (D) Side-by-side view of the complexes of GR and RAF1 with HSP90-CDC37 showing the C-lobe of the RAF1 kinase domain in the opposite site of the GR complex while the MD of CDC37 is positioned in the same area. Detailed view of the superimposition of the complexes depicting the location of the P23 protein. (E) Comparison of CDC37-MD orientation in RHC_c1 and RHCp23_c. Ribbon diagrams of both structures in three perpendicular views; CDC37-MD movement is indicated by black arrows. The dashed line on top of the p23 helical section indicates the proposed modeling. (F) Corresponding cryo-EM maps of these regions, colored by protein. Additional density on CDC37-MD is shown in magenta. (G) Model for p23-assisted release of RAF1 from CDC37-MD in RHC. p23 first binds at the HSP90 dimer interface (1), enabling its flexible tail to contact CDC37-MD (2). This interaction tilts CDC37-MD (3), promoting release of the captured RAF1 N-lobe (5). Alternatively, the p23 tail may compete with the partially unfolded RAF1 N-lobe and block its binding (4). After ATP hydrolysis, the HSP90 dimer opens and releases RAF1 (6).

Article Snippet: Cryo-EM data and processing workflow, related to , , 3, 4, Table S2. (A) Representative motion-corrected cryo-EM micrograph of the RHC particles in vitreous ice imaged with a Titan Krios Falcon 4i direct detector camera (-2.3 μm defocus). (B) Characteristic reference-free 2D averages of the RHC particles.

Techniques: Cryo-EM Sample Prep, Comparison, Blocking Assay, Binding Assay

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A, C ) Representative semithin micrographs of transverse sciatic nerve sections from control and mutant mouse pups at postnatal day 1 with the indicated genotypes. Red arrows depict examples of axons with nascent myelination. Scale bars: 10 µm. ( B, D ) Quantification of myelinated axons in transverse sciatic nerve sections from control and mutant pups at postnatal day 1 with the indicated genotypes. Each dot represents the quantification obtained from one mouse pup. Appendix 1—figure 2—source data 1. Numerical source data (myelinated axon counts) for graphs shown in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques: Control, Mutagenesis

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A ) Representative semithin (first and second columns) and electron micrographs (third column) of transverse sciatic nerve sections of distal nerve stumps from control and the indicated mutant mice 3 days after sciatic nerve transection. Note the complete structural disintegration of transected axons with absent or floccular cytoskeleton and collapsed myelin sheaths in the preparations from control, Tnfrsf21 ΔEx2-3/ΔEx2-3 , and Tnfrsf21 ΔEx2/ΔEx2 mice. In contrast, the majority of disconnected axons from heterozygous Wld S mice, and from Phr1 and SARM1 knockout mice, are structurally preserved with uniform cytoskeleton and intact myelin sheaths. Scale bars: 10 µm. ( B ) Quantification of preserved axons in transverse sciatic nerve sections of distal nerve stumps from mice with the indicated genotypes. Each symbol in the scatter dot plots represents the quantification from one animal (% of control axon numbers in micrographs from uninjured contralateral nerve preparations for each animal). All data were obtained from experimental animals between 3 and 12 months of age. Figure 1—source data 1. Numerical source data (axon survival quantification) for graphs shown in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques: Control, Mutagenesis, Knock-Out

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A ) Representative semithin micrographs of transverse tibial nerve sections of distal nerve stumps from 3-month-old mice with the indicated genotypes (top) 30 hr after sciatic nerve transection with pseudocoloring of intact (turquoise) and structurally degenerated (magenta) myelinated fibers, and corresponding quantifications of relative axon survival (bottom). ( B ) Representative semithin micrographs of transverse tibial nerve sections of distal nerve stumps from 3-month-old mice with the indicated genotypes (top) 36 hr after sciatic nerve transection with pseudocoloring of intact (turquoise) and structurally degenerated (magenta) myelinated fibers, and corresponding quantifications of relative axon survival (bottom). Scale bars: 10 µm. Figure 1—figure supplement 1—source data 1. Numerical source data (relative axon survival quantification) for graphs shown in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques:

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A, C ) Representative immunofluorescence confocal micrographs for c-Jun with DAPI nuclear counterstaining on transverse frozen sections from contralateral uninjured nerve (uncut) and distal sciatic nerve stumps 3 days and 30 hr following axotomy in 3-months-old mice with the indicated genotypes. ( B, D ) Corresponding quantifications of percentage of c-Jun immunoreactive and DAPI + cells on nerve sections. Scale bars: 50 µm. Figure 2—source data 1. Numerical source data (cell counts) for graphs shown in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques: Immunofluorescence

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A ) Representative electron micrographs of transdifferentiated Schwann cells (red arrowheads) that lost axonal contact from distal sciatic nerve stumps 3 days following nerve transection in 3-month-old control and DR6 knockout mice with the shown genotypes. Note the similar ultrastructure with marked cytoplasmic expansion, increased organelle content, and myelin debris (myelin ovoids) in Schwann cell bodies in all genotypes. Scale bar: 2 µm. ( B, C ) Quantification of area occupied by myelin sheaths and myelin debris in transverse nerve sections from 3-month-old control and mutant mice with the indicated genotypes. Each dot represents the quantification obtained from one nerve obtained from one mouse. Figure 2—figure supplement 1—source data 1. Numerical source data (myelin area quantification) for graphs shown in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques: Control, Knock-Out, Mutagenesis

Journal: eLife

Article Title: Death receptor 6 does not regulate axon degeneration and Schwann cell injury responses during Wallerian degeneration

doi: 10.7554/eLife.108389

Figure Lengend Snippet: ( A, D ) Western blot analysis (cropped blot images) of DR6 protein expression in dorsal root ganglia (DRGs) from Tnfrsf21 ΔEx2-3/ΔEx2-3 embryos and from Tnfrsf21 Ex2LoxP/Ex2LoxP embryos infected with a lentivirus expressing Cre recombinase (DR6 Cre ), together with the respective control preparations. ( B, E ) Time course of neurite fragmentation, quantified as degeneration index (DI) (see Materials and methods) in DRG preparations from embryos with the indicated genotypes or lentiviral infection conditions. The data points shown in ( B ) represent the averaged neurite DI values calculated from multiple DRG preparations from each embryo at the indicated time point after injury (one data point = one embryo). The data points shown in ( E ) represent the averaged neurite DI values calculated from multiple micrographs acquired from each DRG preparation in a cell culture well at the indicated time point after injury (one data point = one well). ( C, F ) Representative phase-contrast micrographs of disconnected DRG neurites from embryos with the indicated genotypes and lentiviral infection conditions at the indicated time points after axotomy. Scale bars: 50 µm. Figure 3—source data 1. Numerical source data (degeneration index) for graphs shown in . Figure 3—source data 2. TIF file with original western blots and boxes indicating the relevant bands shown in . Figure 3—source data 3. Original files for western blot analysis displayed in .

Article Snippet: Micrographs (Imaris image format) of the stained cross sections were captured with an Andor Dragonfly 200 spinning disc confocal imaging system (Oxford Instruments) and a 63× high-numerical aperture objective.

Techniques: Western Blot, Expressing, Infection, Control, Cell Culture