Journal: medRxiv

Article Title: A non-coding variant at 2p24.2 confers susceptibility to non-syndromic cleft lip and palate through LLPS-dependent regulation of MYCN

doi: 10.64898/2026.04.07.26350283

Figure Lengend Snippet: (A and B) FOXP2 overexpression upregulates MYCN . (A) Quantification of mRNA (RT-qPCR) and (B) protein levels (western blot) for FOXP2 and MYCN expression in cNCCs transfected with a FOXP2 overexpression vector (OE-FOXP2) or an empty vector control (OE-Mock). Data normalized to GAPDH . Mean ± SD ( n = 3). Unpaired two-tailed Student’s t-test. (C) Predicted FOXP2-binding motif. Schematic representation of the predicted FOXP2-binding sequence including the rs4263114 SNP within Enh- MYCN . (D and E) FOXP2 preferentially binds the non-risk allele at rs4263114. (D) Anti-FOXP2 chromatin immunoprecipitation (ChIP)-qPCR assay validating FOXP2 enrichment at the Enh- MYCN locus in heterozygous (T/G) cNCCs. Normal IgG served as the negative control. Mean ± SD ( n = 3). Two-way ANOVA (Sidak’s post-hoc test). (F) The risk allele abolishes FOXP2-mediated transactivation of Enh- MYCN . Relative luciferase activity of Enh- MYCN reporter constructs harboring either the non-risk (T) or risk (G) allele in HEPM cells co-transfected with OE- FOXP2 or OE-Mock. Mean ± SD (n = 3). One-way ANOVA (Tukey’s post-hoc test).

Article Snippet: For immunoprecipitation, the sheared chromatin was incubated with 2 μg of either anti-FOXP2 antibody (Novus Biologicals, NB100-55411, CO, USA) or normal rabbit IgG (Cell Signaling Technology, 2729S).

Techniques: Over Expression, Quantitative RT-PCR, Western Blot, Expressing, Transfection, Plasmid Preparation, Control, Two Tailed Test, Binding Assay, Sequencing, Chromatin Immunoprecipitation, ChIP-qPCR, Negative Control, Luciferase, Activity Assay, Construct

Journal: medRxiv

Article Title: A non-coding variant at 2p24.2 confers susceptibility to non-syndromic cleft lip and palate through LLPS-dependent regulation of MYCN

doi: 10.64898/2026.04.07.26350283

Figure Lengend Snippet: (A and B) FOXP2 contains a prominent intrinsically disordered region (IDR). Bioinformatic prediction of the FOXP2 IDR sequence using (A) PONDR and (B) PLAAC, providing the structural basis for phase separation. (C) The risk allele disrupts the formation of FOXP2 nuclear condensates. Representative immunofluorescence images of FOXP2 in cNCCs harboring heterozygous (T/G) or homozygous risk (G/G) alleles at rs4263114. Droplet-like FOXP2 condensates are prominent in T/G cells but show a diffuse distribution in G/G cells. Scale bars, 20 μm (left) and 5 μm (right). (D and E) FOXP2 condensates show highly dynamic liquid-like properties. (D) Representative time-lapse fluorescence recovery after photobleaching (FRAP) images of EGFP-FOXP2 overexpressing HEPM cells. Scale bar, 5 μm. (E) Quantification of normalized fluorescence recovery intensity over time ( n = 3 independent experiments). (F) LLPS is required for the allele-specific regulatory activity of Enh- MYCN . Dual-luciferase reporter assay comparing the activity of Enh- MYCN constructs harboring the non-risk (T) or risk (G) allele in HEPM cells upon treatment with 1.5% 1,6-hexanediol (1,6-HD) to chemically disrupt LLPS. Mean ± SD ( n = 3). Unpaired two-tailed Student’s t-test. (G-I) Overexpression of the FOXP2-IDR domain rescues phase separation and MYCN expression in risk-allele cNCCs. (G) Immunofluorescence staining of FOXP2 showing restoration of nuclear condensates in homozygous risk (G/G) cNCCs after FOXP2-IDR overexpression (OE-IDR) versus a Mock-vector baseline (OE-Mock). Scale bar, 10 μm. (H) RT-qPCR and (I) western blot analyses of FOXP2 and MYCN mRNA levels, and their corresponding protein levels, in OE-Mock and OE-IDR G/G cNCCs. Data normalized to GAPDH . For (H) Mean ± SD ( n = 3). Two-way ANOVA (Sidak’s post-hoc test).

Article Snippet: For immunoprecipitation, the sheared chromatin was incubated with 2 μg of either anti-FOXP2 antibody (Novus Biologicals, NB100-55411, CO, USA) or normal rabbit IgG (Cell Signaling Technology, 2729S).

Techniques: Sequencing, Immunofluorescence, Fluorescence, Activity Assay, Luciferase, Reporter Assay, Construct, Two Tailed Test, Over Expression, Expressing, Staining, Plasmid Preparation, Quantitative RT-PCR, Western Blot

Journal: The Journal of Comparative Neurology

Article Title: Immature Excitatory Neurons in the Postnatal Ferret Paralaminar Nuclei and Their Relationship to the Amygdala Across Species

doi: 10.1002/cne.70155

Figure Lengend Snippet: Molecular characterization of Dcx + cells in the juvenile ferret PL . (A and B) Immunofluorescence for Dcx, CoupTFII, and Tbr1 in coronal ferret brain sections at P30 (A) and P67 (B). (C) Immunofluorescence for Dcx + cells in the PL at P30 and P67 showing co‐localization (arrows) or absence of co‐localization (arrowheads) with Tbr1, CoupTFII, or Ctip2. Dcx cells at both ages do not exhibit co‐localization with FoxP2 or Satb2. (D) Quantification of the percentage of Dcx + Tbr1 + and Dcx + CoupTFII + cells. (E) Pie charts showing the percentage of Dcx + cells positive for only one, both, or neither transcription factor at P30, P40, or P67. (F) Representative images of Dcx + Tbr1 + CoupTFII + cells (arrows) and Dcx + Tbr1 − CoupTFII − cells (arrowheads) at P30 and P40. (G) Schematic sagittal section of the ferret brain indicating the locations of the intercalated nuclei (I) and the PL. (H and I) Insets show FoxP2 expression in the intercalated nuclei (I), which are largely Dcx negative at these ages. (J) In the PL (bottom), many Dcx + cells are CoupTFII + and Tbr1 + , but FoxP2 negative. Scale bars: 100 µm (A, B, H, J) and 20 µm (C, F, H magnification, I). BLA, basolateral amygdala; D, dorsal; I, intercalated nuclei; L, lateral; PL, paralaminar nuclei.

Article Snippet: FoxP2 , Goat , 1:500 , IF , Santa Cruz Biotechnology, Cat# 517261; lot # G2216; RRID:AB_2721204 , Inhibitory neurons.

Techniques: Immunofluorescence, Expressing

Journal: Neurobiology of disease

Article Title: Aberrant medial ganglionic eminence (MGE) GABAergic neurogenesis contributes to Huntington’s disease pathogenesis

doi: 10.1016/j.nbd.2026.107297

Figure Lengend Snippet: Dlx1 + arkypallidal GABAergic projection neurons, but not prototypical neurons, are increased in the PND13 BACHD Globus Pallidus. (A/A’–D/D′) Representative immunofluorescence images of the Globus Pallidus from PND13 mice stained for the prototypical neuron marker, PV + cells (A/A’), the arkypallidal neuron marker, Foxp2 (B/B′), EGFP driven by the Dlx1 promoter (C/C′), and combined Foxp2/Dlx1 double labeling (D/D′). (E–H) Quantification of PV + prototypical (E), all Foxp2 + arkypallidal cells (F), Foxp2 + /Dlx1 + arkypallidal cells (G), and Foxp2 + /Dlx1 − cells (H). Data are presented as box-and-whisker plots showing median, interquartile range, and minimum/maximum values. Individual data points represent biological replicates. Statistical comparisons were performed using unpaired Student’s t -test; p < 0.05 was considered significant. Scale bars: 200 μm (A, D).

Article Snippet: For BrdU immunodetection, heat-mediated antigen retrieval was performed in citrate buffer containing 0.05% Tween-20 for 30 min at 100 °C, followed by DNA denaturation in 2 N HCl at 37 °C for 40 min and neutralization in 0.1 M sodium borate buffer (pH 8.0) for 20 min. Primary antibodies included: ChAT (goat anti-ChAT, 1:1000, Sigma-Aldrich, #ab144), BrdU (mouse anti-BrdU, 1:500, R&D systems, #MAB7225), Foxp2 (sheep anti-Foxp2, 1:200, R&D Systems, #AF5647), GFP (chicken anti-GFP, 1:1000, Abcam, #ab13970), Lhx6 (mouse anti-Lhx6, 1:200, Santa Cruz Biotechnology, #sc-271,433), Mafb (rabbit anti-Mafb, 1:200, Cell Signaling Technology, #30919), Nkx2–1 (mouse anti-Nkx2–1, 1:100, Sigma-Aldrich, #MAB5460), NPY (rabbit anti-NPY, 1:500, Cell Signaling Technology, #D745A), phospho-Histone H3 (Rabbit anti-pHH3, 1:300, Cell Signaling Technology, #9701), PV (mouse anti-PV, 1:300, Sigma-Aldrich, #P3086), Satb1 (mouse anti-Satb1, 1:200, Santa Cruz Biotechnology, #sc-376,096), Sox3 (Goat anti-Sox3, 1:500, R&D Systems, #AF2569), SST (rabbit anti-SST, 1:1000, BMA Biomedicals, #T-4103), and VIP (mouse anti-VIP, 1:200, R&D Systems, #576721).

Techniques: Immunofluorescence, Staining, Marker, Labeling, Whisker Assay

Journal: Neurobiology of disease

Article Title: Aberrant medial ganglionic eminence (MGE) GABAergic neurogenesis contributes to Huntington’s disease pathogenesis

doi: 10.1016/j.nbd.2026.107297

Figure Lengend Snippet: The E12.5 BACHD subpallium displays selective alterations of GABAergic precursor cells. Representative immunofluorescence images of the lateral ganglionic eminence [LGE] and ventral pallium [VP] (A–D, A’–D′), the primordium of the globus pallidus (GP; F–G, F′–G’), and the medial ganglionic eminence (MGE) germinative zone (H/H′). Tissue sections were immunostained for Lhx6 (A/A′), Satb1 (B/B′), EGFP driven by the Dlx1 promoter (C/C′), merged staining in A to C (D/D′), Lhx6/Dlx1 (E/E′), Nkx2–1/Dlx1 (F/F′), Lhx6/Foxp2/Dlx1 (G/G′), and VZ/SVZ Nkx2–1/Dlx1 (H/H′). Quantification analyses included LGE mantle: Lhx6 + (I), Satb1 + /Lhx6 + (J), and Mafb + (K); VP: EGFP + driven by the Dlx1 promoter (L), Lhx6 + cells (M), Satb1 + /Lhx6 + (N), and Mafb + (O); Globus Pallidus (GP): Nkx2–1 + (P) and Foxp2 + /Lhx6 + (Q) cells; and MGE VZ/SVZ Nkx2–1 + progenitors (R). Data are presented as box-and-whisker plots showing the median, interquartile range, and minimum/maximum values. Individual data points represent biological replicates. Statistical comparisons were performed using Mann-Whitney U test (I,J,Q) and unpaired Student’s t -test (K, L-P, R); p < 0.05 was considered significant. Scale bars: 50 μm.

Article Snippet: For BrdU immunodetection, heat-mediated antigen retrieval was performed in citrate buffer containing 0.05% Tween-20 for 30 min at 100 °C, followed by DNA denaturation in 2 N HCl at 37 °C for 40 min and neutralization in 0.1 M sodium borate buffer (pH 8.0) for 20 min. Primary antibodies included: ChAT (goat anti-ChAT, 1:1000, Sigma-Aldrich, #ab144), BrdU (mouse anti-BrdU, 1:500, R&D systems, #MAB7225), Foxp2 (sheep anti-Foxp2, 1:200, R&D Systems, #AF5647), GFP (chicken anti-GFP, 1:1000, Abcam, #ab13970), Lhx6 (mouse anti-Lhx6, 1:200, Santa Cruz Biotechnology, #sc-271,433), Mafb (rabbit anti-Mafb, 1:200, Cell Signaling Technology, #30919), Nkx2–1 (mouse anti-Nkx2–1, 1:100, Sigma-Aldrich, #MAB5460), NPY (rabbit anti-NPY, 1:500, Cell Signaling Technology, #D745A), phospho-Histone H3 (Rabbit anti-pHH3, 1:300, Cell Signaling Technology, #9701), PV (mouse anti-PV, 1:300, Sigma-Aldrich, #P3086), Satb1 (mouse anti-Satb1, 1:200, Santa Cruz Biotechnology, #sc-376,096), Sox3 (Goat anti-Sox3, 1:500, R&D Systems, #AF2569), SST (rabbit anti-SST, 1:1000, BMA Biomedicals, #T-4103), and VIP (mouse anti-VIP, 1:200, R&D Systems, #576721).

Techniques: Immunofluorescence, Staining, Whisker Assay, MANN-WHITNEY

Journal: Cell reports

Article Title: RNA-programmable cell-type monitoring and manipulation in the human cortex with CellREADR

doi: 10.1016/j.celrep.2025.116037

Figure Lengend Snippet: (A) Human organotypic slice model. The human neocortex (middle and inferior temporal gyri; left) was sectioned at 350 μm and cultured on semi-permeable membranes for up to 16 days in vitro (DIV; right). CellREADR AAV vectors were applied to slices on DIV0. Orientation: A, anterior; D, dorsal; P, posterior; V, ventral. (B) Schematic of CellREADR design. In the single-virus design (left), binding of the sensor to the target initiates ADAR-mediated editing of a stop codon to express the downstream effector (mNeon). The binary system (right) uses a CellREADR virus (top right) to drive expression of tTA2 (Tet-advanced transactivator). A reporter virus, conditionally expressing a selected effector molecule (e.g., mNeon, ChIEF, or GCamp7f) under the control of the Tet-responsive element (TRE), is co-applied. (C) CellREADR targeting of diverse neuronal populations. Binary CellREADRs (mNeonGreen) designed against somatostatin ( SST ), Unc-5 netrin receptor B ( UNC5B ), parvalbumin ( PVALB ), forkhead box protein P2 ( FOXP2 ), and calretinin ( CALB2 ) were applied to the neocortex of at least 3 donors. Slices were immunostained for mNeon at DIV7. The CellREADR binary system drove robust expression of mNeon in differing lamina and in cells of various morphologies. Magnified images are indicated by dashed red boxes; throughout, pia and white matter (WM) are illustrated with dotted lines. Scale bars: 200 μm (large image) and 50 μm (magnified image). (D) Histological analysis of binary FOXP2 and CALB2 CellREADR targeting. CellREADR mNeon distribution (green, left) and protein expression of target (purple, middle) are depicted at DIV7. Fluorescence intensity profiles at far left reveal the depth distribution of cells targeted by CellREADR. Dashed boxes indicate areas depicted in (F). Scale bars: 200 μm. (E) Localization of CellREADR-targeted cells. CellREADR mNeon fluorescence intensity profiles measured across the depth of the cortex (0% = pial surface, 100% = WM boundary) averaged from 6 slices (tissues from 3 donors). The solid line shows the mean; the shaded area shows the SEM. FOXP2 -mNeon was relatively uniform throughout cortical layers, while CALB2 -mNeon was more restricted to outer layers. (F) Immunohistochemical characterization of CellREADR specificity. Representative images showing colocalization of CellREADR-mNeon with the corresponding target. Scale bars: 50 μm. (G) Quantification of CellREADR specificities as measured by immunostaining. Each point denotes the specificity of labeling measured from an individual donor’s tissue ( FOXP2 , n = 5 donors; binary CALB2 , n = 7; singular CALB2 , n = 3). Horizontal bars indicate mean specificity values for each CellREADR. Throughout the figures, data are presented as mean ± SEM. (H) Benchmarking CellREADR efficiency with a human interneuron enhancer virus DLX2.0-YFP. CALB2 CellREADR and DLX2.0-YFP viruses (rAAV2-retro) were applied to slices cut sequentially from the same neocortical tissue specimen. Tissue was immunostained at DIV7 against mNeon or YFP. Slice boundaries are indicated by the solid white line, and the WM is demarcated by a dashed white line; boxes mark the inset images on the bottom. Scale bars: 1 mm (top images) and 200 μm (bottom images). (I) Localization of DLX2.0-YFP expression. Representative image illustrating the efficiency and distribution of labeling achieved with a DLX2.0-YFP virus (left), with fluorescence intensity profile (right; averages from 3 donors) illustrating the distribution of labeled cells. Compared to CALB2 CellREADR labeling (D and H), DLX2.0-YFP + cells were less concentrated in the outer cortex. Scale bar: 250 μm. (J) DLX2.0-YFP targeting of the CALB2 population. Quantification of colocalization of DLX2.0-YFP expression and CALB2 measured by immunostaining (images not shown); note the inter-subject variability in the targeting of CALB2 cells ( n = 7 donors). (K) Efficiency of binary and singular CALB2 CellREADRs compared to DLX2.0-YFP enhancer virus. Quantification of cells labeled at DIV7 per unit area (binary CALB2 , n = 6 donors; singular CALB2 , n = 3; DLX2.0-YFP, n = 3). Note that although the CellREADRs were designed to target only CALB2 interneurons rather than multiple interneuron subclasses, they labeled more cells than the DLX2.0 virus (one-way ANOVA with Tukey’s post hoc).

Article Snippet: The following antibodies were used for immunohistochemical labeling of mNeon, mCherry, FoxP2, Calretinin and NeuN: mouse anti-mNeon Ab 1:500, Proteintech 32f6; chicken anti-mCherry Ab 1:500, Origene TA150127; rabbit anti-FoxP2 Ab 1:500, Abcam ab16046; rabbit anti-Calretinin Ab 1:500, Swant CR7697; mouse anti-NeuN Ab 1:500, Cell Signaling #94403S.

Techniques: Cell Culture, In Vitro, Virus, Binding Assay, Expressing, Control, Fluorescence, Immunohistochemical staining, Immunostaining, Labeling

Journal: Cell reports

Article Title: RNA-programmable cell-type monitoring and manipulation in the human cortex with CellREADR

doi: 10.1016/j.celrep.2025.116037

Figure Lengend Snippet: (A) Reference gene expression profiles of human MTG interneurons described in a prior study. CALB2 expression is largely restricted to VIP subclass interneurons, indicating that the CALB2 READR should primarily target VIP interneurons. Of the 19 CALB2 READR-targeted cells studied by PatchSeq, all but 1 cell mapped to the VIP subclass (transcriptomic types of the 19 cells are listed at right; the number indicates count of cells) according to the classification scheme adapted from Tasic et al. and Hodge et al. (B) Expression of selected genes in CALB2 READR cells. CALB2 transcripts were detected in all but 1 cell, which was mapped onto the SST subclass. READR-targeted cells rarely expressed canonical markers of interneuron subclasses other than VIP (e.g., LAMP5 , SST , and PVALB ). Interestingly, 5 of the 6 cells that mapped to the PAX6 SYT6 type expressed the SLC17A 7 (vesicular glutamate transporter 1), which is expressed widely across human MTG glutamatergic populations ; these cells also expressed the GABAergic marker GAD1 . (C) PatchSeq electrophysiological measures of CALB2 READR-targeted neurons. Input-output curves illustrate the variation in rheobase, gain, and maximum firing frequency across the sampled population. The interrelationship between gene expression and physiological properties is further illustrated in . (D) Variation in electrophysiological properties across and within interneuron transcriptomic types. Membrane responses to depolarizing and hyperpolarizing currents from cells mapped to the same transcriptomic types. Cells mapped to the PAX6 SYT6 type exhibited variation in the frequency and accommodation of action potential firing and exhibited varying responses to hyperpolarization. Scale bars: 20 mV, 200 ms. (E) Morphologies of CALB2 READR-targeted cells from the PatchSeq subset. Laminar positions of reconstructed neurons are illustrated at the top. Blue circles indicate somata (not to scale), and profiles indicate the vertical and horizontal densities of dendrites (black) and axons (red). Cortical depth is indicated on the left vertical axis; average layer boundaries are shown on the right vertical axis. Complete cell tracings are shown at the bottom. shows morphologies of additional CALB2 - and FOXP2 -targeted cells. The morphology of READR-targeted interneurons was also compared to those targeted previously using a distinct method . Scale bars: 200 μm.

Article Snippet: The following antibodies were used for immunohistochemical labeling of mNeon, mCherry, FoxP2, Calretinin and NeuN: mouse anti-mNeon Ab 1:500, Proteintech 32f6; chicken anti-mCherry Ab 1:500, Origene TA150127; rabbit anti-FoxP2 Ab 1:500, Abcam ab16046; rabbit anti-Calretinin Ab 1:500, Swant CR7697; mouse anti-NeuN Ab 1:500, Cell Signaling #94403S.

Techniques: Gene Expression, Expressing, Marker, Membrane

Journal: Cell reports

Article Title: RNA-programmable cell-type monitoring and manipulation in the human cortex with CellREADR

doi: 10.1016/j.celrep.2025.116037

Figure Lengend Snippet: (A) Passive membrane properties of cells targeted by CALB2 ( n = 60 cells) and FOXP2 ( n = 43 cells) CellREADRs. Membrane capacitance and input resistance, but not hyperpolarizing sag ratio or resting membrane potential, differed between the two populations. Black bars indicate mean and SEM (Mann-Whitney U-test for non-normal distributions, t test for normal distributions). (B) Active properties of cells targeted by CALB2 ( n = 60) and FOXP2 ( n = 43) CellREADRs. Firing responses in response to current injections, with frequency plotted against current step. Insets show action potentials (APs) elicited by current injections at 2× rheobase; these examples were selected to represent the mean input-output curves for each cell type (black). The rheobase, gain, max firing frequency, and the coefficient of variation of the AP inter-spike interval all differed statistically between CALB2 - and FOXP2 -targeted populations (Mann-Whitney U-test or t test). Cross-correlations between all physiological properties are presented in . (C) AP properties of cells targeted by CALB2 ( n = 60) and FOXP2 ( n = 43) CellREADRs. APs were elicited with a 2 ms current step. AP properties from different stimulation regimes are presented in . AP half-width was measured at 50% of peak voltage and was found to be smaller in CALB2 -targeted cells. AP height and threshold did not vary between target cell groups. The fast afterhyperpolarization (fAHP) following the AP was larger in CALB2 -targeted cells. APs were aligned on their rising phase to compare waveforms between target cell groups (bottom). Group means are illustrated by black lines. CALB2 -targeted cells exhibited a shorter AP duration and a smaller afterdepolarization than FOXP2 -targeted cells (Mann-Whitney U-test or t test). Scales bars: 20 mV, 2 ms (left); 20 mV, 2 ms (middle); and 5 mV, 20 ms (right). (D) Subthreshold synaptic activity and suprathreshold firing were observed in targeted cells. Excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs, respectively) were detected in both CALB2- and FOXP2- targeted populations. Representative traces demonstrating EPSPs and IPSPs in cells of both populations are shown. Scale bars: 1 mV, 200 ms. (E) Recorded cells exhibited spontaneous firing from their resting potentials. Examples of spontaneous firing activity observed in CALB2 - (red, n = 3 cells) and FOXP2 - (blue, n = 3) targeted cells are illustrated, with average firing frequencies (observed over a 3 min period) indicated at right. Scale bars: 20 mV, 1,000 ms. (F) CALB2 -targeted cells ( n = 66 cells) were more likely than FOXP2 -targeted cells ( n = 50) to exhibit spontaneous firing (chi-squared test). (G) Spontaneous activity, measured as the frequency of spontaneous AP firing, differed between CALB2 - and FOXP2 -targeted populations (Mann-Whitney U test). (H) Traces demonstrating spontaneous AP firing from CALB2 - (red) and FOXP2 - (blue) targeted cells in either baseline conditions (left) or in the presence of glutamatergic blockers (right). Scale bars: 20 mV, 1,000 ms. (I) Glutamatergic blockers (CNQX/AP-5) reduced spontaneous firing frequency in most cells ( CALB2 , n = 6 cells; FOXP2 , n = 2) but did not eliminate firing in every cell.

Article Snippet: The following antibodies were used for immunohistochemical labeling of mNeon, mCherry, FoxP2, Calretinin and NeuN: mouse anti-mNeon Ab 1:500, Proteintech 32f6; chicken anti-mCherry Ab 1:500, Origene TA150127; rabbit anti-FoxP2 Ab 1:500, Abcam ab16046; rabbit anti-Calretinin Ab 1:500, Swant CR7697; mouse anti-NeuN Ab 1:500, Cell Signaling #94403S.

Techniques: Membrane, MANN-WHITNEY, Activity Assay

Journal: Cell reports

Article Title: RNA-programmable cell-type monitoring and manipulation in the human cortex with CellREADR

doi: 10.1016/j.celrep.2025.116037

Figure Lengend Snippet: Cell-type-specific optical manipulation of human neurons with CellREADR (A) CellREADR expression of an optogenetic effector, ChIEF, enables optogenetic control of AP firing in CALB2 - but not FOXP2 -targeted cells. CALB2- ChIEF neurons fired in response to 100 ms, 642 nm light pulses (left) or trains of 2 ms pulses (6/6 cells fired APs in response to both stimuli, with some failures in the train). Light stimuli depolarized FOXP2 -ChIEF but did not drive AP firing (0/10 cells fired in response to stimuli; gray traces, individual trials from a single cells; black traces, averages). Scale bars: 20 mV, 20 ms, 50 ms. (B) Representative targeting scheme for optical interrogation of CALB2 synaptic connectivity. Putative postsynaptic cells were labeled with a DLX2.0-YFP virus (top left, green). A binary CellREADR vector driving CALB2 -ChIEF-tdTomato was used to activate presynaptic cells (top right, red). During optical stimulation of the ChIEF-tdTomato + population, patch-clamp recordings were made from YFP + /ChIEF-tdTomato − cells; at the end of recordings, biocytin-filled patched cells were recovered (bottom right, purple, biocytin-streptavidin [SAV]). Scale bar: 50 μm. (C) Postsynaptic currents elicited by CALB2-ChIEF activation. Voltage-clamp recordings (average of 10 trials) made from a DLX2.0-YFP + /ChIEF-tdTomato − neurons during optical stimulation of the CALB2 -ChIEF population (left). Stimulation elicited optical postsynaptic currents (oPSCs) at the glutamate reversal potential (V rev(Glu) ) but not at the GABA reversal potential (V rev(GABA) ). Bicuculline was applied to verify that the observed oIPSCs were GABAergic. In DLX2.0-YFP + /ChIEF-tdTomato − cells, oPSCs were never observed at V rev(GABA) . Averaged traces were recorded from a hSyn-mCherry + pyramidal neuron during optical stimulation of the CALB2 -ChIEF population (right). In this example, oPSCs were detected at V rev(GABA) but not V rev(Glu) , indicating that the cell received glutamatergic inputs. These inputs were not blocked by bicuculline. No cell exhibited oPSCs at both V rev(GABA) and V rev(Glu) . Scale bars: 0.2 pA, 50 ms (left) and 2 pA, 50 ms (right). (D) Failure rate of optically triggered synaptic currents. To illustrate trial-to-trial variability in oPSC responses, 10 trials from a DLX2.0-YFP + /ChIEF-tdTomato − cell are shown at V rev(Glu). The first light pulse had a failure rate of 10% (1/10), while the fourth light pulse had a failure rate of 40% (4/10; averaged response, black). Scale bar: 2 pA, 50 ms. (E) Waveforms of optically evoked postsynaptic responses. Optical PSCs measured at V rev(Glu) from DLX2.0-YFP + /ChIEF-tdTomato − interneurons and hSyn-mCherry + pyramidal neurons were aligned to the light pulse and overlaid (left). All oPSCs were normalized to the peak current (right). The monophasic rise time and small jitter relative to the 2 ms light stimulus indicate that PSCs were monosynaptic events directly triggered by the optical pulse (averaged response, black). Scale bars: 2 pA, 10 ms (left) and 0.2 pA, 5 ms (right). (F) Quantification of postsynaptic responses to CALB2 -ChIEF activation. When recordings were made from DLX2.0-YFP + / CALB2 -ChIEF − interneurons, oIPSCs were observed in 6/16 cells (37.5%), and oEPSCs were not detected. Recordings were also made from hSyn-tdTomato + pyramidal neurons during CALB2 -ChIEF activation. oIPSCs were detected in 3/14 cells (21.4%), and oEPSCs were detected in 2/14 cells (14.3%).

Article Snippet: The following antibodies were used for immunohistochemical labeling of mNeon, mCherry, FoxP2, Calretinin and NeuN: mouse anti-mNeon Ab 1:500, Proteintech 32f6; chicken anti-mCherry Ab 1:500, Origene TA150127; rabbit anti-FoxP2 Ab 1:500, Abcam ab16046; rabbit anti-Calretinin Ab 1:500, Swant CR7697; mouse anti-NeuN Ab 1:500, Cell Signaling #94403S.

Techniques: Expressing, Control, Labeling, Virus, Plasmid Preparation, Patch Clamp, Activation Assay

Journal: Cell reports

Article Title: RNA-programmable cell-type monitoring and manipulation in the human cortex with CellREADR

doi: 10.1016/j.celrep.2025.116037

Figure Lengend Snippet: (A) Correlation between AP firing and GCamp7f signals. APs (black) were elicited by current injections in single cells expressing either CALB2 -GCamp7f ( n = 4 cells) or FOXP2 -GCamp7f ( n = 4). Calcium transients (green) were concurrently imaged at the cell soma and proximal dendrite. Traces show 6 APs and the resultant GCaMP signal measured from a CALB2 -GCamp7f cell (top left, current injection represented by gray box; top inset shows the voltage trace at an expanded timescale). The relationship between the baseline-subtracted change in fluorescence and AP firing (right) was established by varying the current injection, counting APs, and making a linear fit of ΔF/F versus AP counts ( CALB2 : R 2 = 0.84; FOXP2 : R 2 = 0.93). Scale bars: 20 mV, 100 ms (inset) and 20 mV, 2,000 ms. (B) Calcium imaging detects subthreshold events as well as APs. Recording of a CALB2 -GCaMP7f demonstrating three evoked APs (black trace, at gray box) followed by a spontaneous subthreshold depolarization and then a single spontaneous AP. The calcium transient for these three events (green) is depicted; the rise times for each event were as follows: Tau 3AP = 390 ms, Tau Depolarization = 1,760 ms, and Tau 1AP = 202 ms. Scale bars: 20 mV, 100 ms (inset) and 20 mV, 2,000 ms. (C) Maximum projection of CALB2 -GCamp7f (left, red) and FOXP2 -GCamp7f (right, blue) neurons measured in baseline conditions. Background-subtracted fluorescent profiles of somata were collected from 90 s video stacks (red and blue traces). CellREADR typically labeled 10–50 cells within a field of view. Scale bars: 50 μm, 20 s. (D) Color maps depicting population calcium signal dynamics. Calcium signals from slices labeled with CALB2 -GCamp7f (left, red; n = 6 slices) or FOXP2 -GCamp7f (right, blue n = 7) cells are represented by a color map (intensity scale at bottom; each map represents a recording performed on a single slice; slices are from 4 donors). Spontaneous activity levels varied between slices. Calcium signals from selected individual cells are depicted to the right of the color maps; most transients were small-amplitude, fast-rising events, similar to the transients produced by APs in (A). Large-amplitude, slow-rising transients (marked with asterisks) similar to the subthreshold events in (B) were also observed. Scale bars: 20 s (population maps) and 10 s (individual traces). (E) Correlated calcium events in slice populations. The correlation of cellular CALB2 -GCaMP7f ( n = 6 slices) or FOXP2 -GCaMP7f ( n = 7) calcium signals was measured within each slice and then compared between groups ( CALB2- and FOXP2 -targeted populations). Calcium signals were more strongly correlated in the FOXP2 -targeted population (unpaired t test). (F) Calcium signal responses to nicotinic acetylcholine receptor activation. Nicotine (300 μM) was applied to a subset of slices following imaging baseline activity. Each image represents a region of interest (ROI) in a single slice labeled with either CALB2 -GCaMP7f (left, red; n = 3 slices) or FOXP2 -GCaMP7f (right, blue; n = 3). Scale bar: 20 s. (G) Nicotine application did not change the proportion of active cells within the labeled populations ( CALB2 , p = 0.08; FOXP2 , p = 0.999; Fisher’s exact test). However, nicotine application increased the area of measured calcium events, normalized to baseline in CALB2 -targeted cells (two-way ANOVA with Fisher’s least significant difference [LSD] post hoc). The dashed line on both graphs represents unity.

Article Snippet: The following antibodies were used for immunohistochemical labeling of mNeon, mCherry, FoxP2, Calretinin and NeuN: mouse anti-mNeon Ab 1:500, Proteintech 32f6; chicken anti-mCherry Ab 1:500, Origene TA150127; rabbit anti-FoxP2 Ab 1:500, Abcam ab16046; rabbit anti-Calretinin Ab 1:500, Swant CR7697; mouse anti-NeuN Ab 1:500, Cell Signaling #94403S.

Techniques: Expressing, Injection, Fluorescence, Imaging, Labeling, Activity Assay, Produced, Activation Assay