Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Schematic representation of the transgenic strategy to ablate M/T cells at early postnatal stages. The Tbx21 promoter is specific for M/T cells. The Tbx21 transgene controls the expression of the Cre recombinase in M/T cells, thus regulating the selective expression in M/T cells of the subunit A of the diphtheria toxin (DTA), from a CAG::loxp stop Rosa26 DTA reporter mouse. ( B ) Schematic representation of the two possible scenarios expected after M/T cell ablation. (top) Reduction of M/T cells density during early postnatal maturation does not affect the apical dendrite refinement. (bottom) The lack of peer M/T cells interferes with the normal refinement of the apical dendrite, thus retaining an immature morphology with multiple apical dendrites. ( C ) Quantification of the number of remaining M/T cells (tdT positive cells) in the OB at different times after early postnatal cell ablation in Tbx21::DTA mice crossed with the Ai9 reporter mouse. In Tbx21::DTA::Ai9 mice, approximately 25% of the M/T cells remained at P10 (9,606.5±1,229.7; n=4),~3% at P21 (1,024.8±282.3; n=9), and ~1% at P120 (437.6±119.2; n=8) compared with wild type (Tbx21) mice at P120 (38,546.8±2,912.2; n=3). Data are shown as average ± standard deviation. ( D ) Confocal images of individually labeled M/T cells in the OB of a P10 Tbx21::DTA::Confetti mouse after early postnatal cell ablation. Note that M/T cells present a single apical dendrite innervating a glomerulus. Scale bar is 100 µm. ( E ) Confocal images of labeled M/T cells in the OB of a P21 Tbx21::DTA::Ai9 mouse after early postnatal cell ablation. Note that M/T cells present a single apical dendrite innervating a single glomerulus. Scale bar is 100 µm. ( F ) Percentage of M/T cells with an apical dendrite innervating one or two glomeruli in P10 and P21 mice after early postnatal cell ablation. Figure 1—source data 1. Progressive loss of M/T cells after early postnatal ablation does not affect apical dendrite refinement of remaining M/T cells.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Transgenic Assay, Expressing, Standard Deviation, Labeling

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Coronal section to the OB in a P0 Tbx21::Ai9 mouse. There is a high number of M/T cells that express tdT, indicating that Cre enzyme is active at embryonic stages in a significant fraction of M/T cells. ( B ) Coronal section to the OB in a P3 Tbx21::Ai9 where most, if not all, the M/T cells are expressing tdT protein. DAPI staining (blue) labels cell nuclei. Scale bar in B is 200 µm and applies to A-B.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Expressing, Staining

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) (left) Weight of Tbx21::DTA (red bar) and Tbx21::iDTR (blue bar) males mice compared with their wild type siblings (grey bar). Significant differences were observed in their weights. Tbx21::DTA (27.7±2.8gr; n=19) vs Tbx21 (30.1±3.4gr; n=19), p-value = 0.03. Tbx::iDTR (26.5±1.5gr; n=12) vs Tbx21 (28.2±2.2gr; n=11), p-value = 0.02. (right) Weight of Tbx21::DTA (red bar) and Tbx21::iDTR (blue bar) females mice compared with their wild type siblings (grey bar). No significant differences were observed in their weights. Tbx21::DTA (24±2.8gr; n=19) vs Tbx21 (25.4±3.9 gr; n=19), p-value = 0.22. Tbx21::iDTR (22.3±1.7gr; n=22) vs Tbx21 (22.8±2.2gr; n=11), p-value = 0.19. ( B ) Dorsal view of Tbx21, Tbx21::DTA, and Tbx21::iDTR brains. Note that the OBs of the Tbx21::DTA and Tbx21::iDTR brains are significantly smaller than in Tbx21 brains (wild type). ( C ) Coronal sections through the Tbx21::Ai9, Tbx21::DTA::Ai9, and Tbx21::iDTR::Ai9 OBs. M/T cells expressing the tdT fluorescent protein are labeled in red. Note that in the OB of Tbx21::DTA::Ai9 and Tbx21:iDTR::Ai9 mice there are much fewer M/T cells labeled compared with the OB in the Tbx21::Ai9 mouse (left). blue = DAPI staining. Scale bar is 300 µm. ( D ) Quantification of the OB volume in the wild type (Tbx21; n=3) and the two experimental mice (Tbx21::DTA (n=3), and Tbx21::iDTR (n=3)), including the volume for each layer in the OB. The OB volume in Tbx21:DTA and Tbx21::iDTR mice is reduced to half of wild type OB. ( E ) Confocal images of coronal sections to the OB after immunostaining with Tbr2 (red; a marker for OB excitatory neurons), TH (green; a marker for a subpopulation of PGCs), and DAPI (blue; a nuclear stain). Note that the number of Tbr2+ cells is strongly reduced in Tbx21::DTA and Tbx21::iDTR mice compared to Tbx21 mice. Scale bar is 100µm. Figure 1—figure supplement 2—source data 1. M/T cell ablation in young and adult mice induces changes in animal weight and olfactory bulb volume.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Expressing, Labeling, Staining, Immunostaining, Marker

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Confocal images of M/T cells in P10 Tbx21::DTA::Confetti mice after cell ablation soon after birth. Most M/T cells showed a normal morphology, with a single apical dendrite innervating a single glomerulus. Scale bar is 100 µm.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques:

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Schematic representation of the transgenic strategy to ablate M/T cells in adult animals. The Tbx21 promoter is specific for M/T cells. The Tbx21 transgene controls the expression of the Cre recombinase in M/T cells, enzyme, thus regulating the selective expression in M/T cells of the receptor (iDTR) for diphtheria toxin (DT), from a CAG:loxp stop Rosa26 iDTR reporter mouse. Upon systemic injection of DT into the bloodstream, DT gets transported into M/T cells expressing iDTR, and selectively kills them. ( B ) Two possible scenarios are expected after ablating most of the M/T cells in adult animals. (top) M/T cells density reduction does not induce changes in the apical dendrite structure. (bottom) The absence of peer M/T cells induces structural plasticity in remaining M/T cells, whose apical dendrites extend into nearby glomeruli. ( C ) Quantification of the number of remaining M/T cells (tdTomato [tdT] positive cells) in the OB of adult mice (P120) in different cell ablation experiments. 437.6±119.2 M/T cells remained in Tbx21::DTA::Ai9 mice (~1% of the full set of M/T counted in wt mice; n=8; light red). 1158±99 M/T cells remained in Tbx21::iDTR::Ai9 mice (~3% compared to wt mice; n=4; light green). 9819±1544 M/T cells remained in Tbx21::iDTR::Ai9 mice when half of the DT concentration (10 μg/kg of body weight) was injected (~25% compared to wt; n=3; dark green). Wild type (Tbx21::Ai9) mice had 38,546.8±2912.2; n=3; gray. Data are shown as average ± standard deviation. ( D–H ) Confocal images of M/T cells after sparse labeling using AAV-PHP.eB-DiO-GFP. ( C ) Tbx21 (wild type) mice at P120. ( D ) Tbx21::DTA mice at P120. ( E ) Tbx21::iDTR mice at P120 (cell ablation induced at P60). ( F ) Tbx21::iDTR mice at P240 (cell ablation induced at P180). ( G ) Tbx21::iDTR mice at P120 (cell ablation induced at P60 using half of the DT dose). Blue = DAPI staining. Scale bar in H is 50 µm and applies to ( D-H ). ( I ) Percentage of M/T cells with an apical dendrite innervating one, two, three or more glomeruli for experimental conditions in D-H. In Tbx21::DTA ~35% of M/T cells had an apical dendrite innervating more than one glomerulus, while in control mice (Tbx21) ~99% M/T cells had an apical dendrite innervating a single glomerulus (Tbx21 (n=158) and Tbx21::DTA (n=149); p-value <0.0001; χ2 test). In Tbx21::iDTR mice, when ablation was induced at P60, 48% of M/T cells had an apical dendrite innervating more than one glomerulus (n=188; p-value = <0.0001, compared to Tbx21), but no significant differences were observed when compared to Tbx21::DTA (p-value = 0.05). No significant differences were observed in Tbx21::iDTR mice when comparing cell ablation performed at P60 versus P180 (n=236; p-value = 0.15) or P60 versus M/T cells ablation using half-dose of DT at P60 (n=308; p-value = 0.05). Figure 2—source data 1. M/T cell density reduction induces changes in the apical dendrite structure.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Transgenic Assay, Expressing, Injection, Concentration Assay, Standard Deviation, Labeling, Staining, Control

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Confocal images of M/T cells at P120 labeled with AAV-PHP.eB-DiO-GFP in Tbx21::DTA and ( B ) Tbx21::iDTR mice (cell ablation performed at P60). ( C ) M/T cells in Tbx21::iDTR mice at P240 (cell ablation at P180). ( D ) M/T cells in Tbx21::iDTR at P120 (cell ablation at P60 using half the DT dose). Blue = DAPI staining. Scale bar in D is 50 µm and applies to A-D.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Labeling, Staining

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: Quantification of the apical dendrite tuft length of remaining M/T cells after cell ablation in experimental conditions as in . Significant differences were observed when the tuft length of M/T cells in Tbx21 mice (6234.2±2542.4 µm, n=22) was compared to M/T cells in Tbx21::DTA (12,889.5±6609.3 µm; n=24; p<0.0001), and Tbx21::iDTR mice (cell ablation at P60; 14,211.5±7324.5 µm; n=24; p<0.0001; Mann Whitney U test). No significant differences were observed when comparing ablation performed at P60 versus P180 in Tbx21::iDTR mice (cell ablation at P180; 11,583.4±5504.6 µm; n=31; p-value = 0.72) or using half of the DT doses in P60 Tbx21::iDTR mice (13,122.8±6402.7 µm; n=24; p-value = 0.29). Data is shown as average ± S.E.M. Figure 2—figure supplement 2—source data 1. Apical dendrite tuft length of remaining M/T cells.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: MANN-WHITNEY

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) (left) Schematic representation of the strategy to perform sensory deprivation (naris occlusion) in Tbx21::iDTR prior to cell ablation induced at P60. (right) Two possible scenarios are expected in the remaining M/T cells of sensory deprived OBs. (left cartoon) Sensory deprivation prevents the structural changes of M/T caused by ablation of M/T peers and retain a single apical dendrite, or (right cartoon) M/T cells undergo structural plasticity in sensory deprived OB, as shown in . ( B ) Confocal images of M/T cells labeled using AAV-PHP.eB-DiO-GFP showing that remaining M/T cells in the OBs sensory deprived by naris closure (middle) in Tbx21::iDTR mice still remodeled their apical dendrites, such that they branch toward multiple nearby glomeruli, as observed in the contralateral OB with an open naris (right), or in control Tbx21::iDTR mice in which both nares were left open (left). Blue = DAPI staining. Scale bar in B is 50 µm. ( C ) Schematic representation of the strategy to selectively reduce neuronal activity in M/T cells in Tbx21::iDTR by expressing the Kir2.1 channel before inducing cell ablation at P60. Two possible scenarios are expected in the remaining M/T cells. Neuronal activity reduction prevents the structural changes of M/T caused by ablation of M/T peers and retain a single apical dendrite, or M/T cells with reduced neuronal activity undergo structural plasticity in sensory deprived OB, as shown in . ( D ) Confocal images of M/T cells labeled using AAV-PHP.eB-DiO-Kir2.1–2 A-GFP show that M/T cells expressing the Kir2.1 channel in the remaining cells when cell ablation was performed in Tbx21::iDTR mice, showed structural changes in their apical dendrite (right). M/T cells expressing the Kir2.1 channel without cell ablation maintained their normal morphology, with a single apical dendrite innervating a single glomerulus. Blue = DAPI staining. Scale bar in D is 50 µm. ( E ) Percentage of M/T cells with apical dendrites innervating one, two, three or more glomeruli for experimental conditions shown B and D. Similar results were obtained in M/T cells from both OBs, closed (38%; n=231) or open (44%; n=228) nostril. No significant differences were observed between Tbx21::iDTR mice with open versus closed nostrils (p-value = 0.17; χ2 test). Similarly, in Tbx21::iDTR animals that received a DT injection (Tbx21::iDTR +DT) at P60 the expression of the Kir2.1 channel (Tbx21::iDTR +DT + Kir) did not cause any significant changes in the morphology of M/T cells (p-value = 0.05). Figure 3—source data 1. Neuronal activity does not regulate the plasticity of apical dendrites.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Labeling, Control, Staining, Activity Assay, Expressing, Injection

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A–D ) Confocal images of coronal sections through the OB of a Tbx21 ( A and B ) and Tbx21::iDTR ( C and D ) mice labeled with tyrosine hydroxylase antibody (TH, red) which labels a subset of periglomerular cells input. Upon sensory deprivation, the levels of TH are strongly reduced in PGs ( A, C ) Sensory deprived OBs in wild type ( A ) and Tbx21::iDTR ( C ) mice. ( B, D ) Open OBs in wild type ( B ) and Tbx21::iDTR ( D ) mice. Blue = DAPI staining. Scale bar in D is 50 µm and applies to A-D.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Labeling, Staining

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: Quantification of the apical dendrite tuft length of remaining M/T cells after cell ablation in experimental conditions as in . Significant differences were observed when comparing the tuft length of M/T cells in the sensory deprived OB (closed nostril; 9176.9±3328.1 µm; n=30) to those in the contralateral open OB (open nostril; 12,276.9±5968.9 µm; n=23; p-value = 0.045), and control mice (Tbx21::iDTR; 14,211.5±7324.5 µm; n=24; p-value = 0.025; Mann Whitney U test). Significant differences were observed when comparing the tuft length of remaining M/T cells expressing the Kir2.1 channel in Tbx21::iDTR injected with DT (9642.7±4841.9 µm; n=19) with M/T cells expressing the Kir2.1 channel in control Tbx21::iDTR mice that did not receive any DT injection (Tbx21::iDTR; 6417.9±2505.4 µm; n=20; p-value = 0.019). Data are shown as average ± S.E.M. Figure 3—figure supplement 4—source data 1. Apical dendrite tuft length of remaining M/T cells with reduced neuronal activity.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Control, MANN-WHITNEY, Expressing, Injection, Activity Assay

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A–B ) Confocal images of remaining M/T cells labeled using AAV-PHP.eB-DiO-GFP in a P120 Tbx21::iDTR mice where unilateral naris occlusion was performed at P50, 10 days before cell ablation was started ( P60 ). Note that the remaining M/T cells in sensory deprived OBs ( A ) still remodel their apical dendrites, such that they branch toward multiple nearby glomeruli, as remaining M/T cells in the open OB ( B ). Blue = DAPI staining. ( C ) Confocal images of M/T cells sparsely infected with an AAV-PHP.eB-DiO-Kir2.1–2 A-GFP in a P120 Tbx21::iDTR mice that did not receive any DT injection (control mice). Note that M/T cells expressing the Kir2.1 channel in a normal cell density had a single apical dendrite innervating a single glomerulus. ( D ) Confocal images of M/T cells labeled using AAV-PHP.eB-DiO-Kir2.1–2 A-GFP in a P120 Tbx21::iDTR mice where M/T cells express the Kir2.1 channel before cell ablation was started at P60. Note that the remaining M/T cells, even when their firing was strongly reduced by the Kir2.1 expression, branch to several nearby glomeruli. Blue = DAPI staining. Scale bar in D is 50 µm and applies to A-D.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Labeling, Staining, Infection, Injection, Control, Expressing

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Example of membrane potential traces in response to current steps of various amplitudes. Recorded from one M/T cell in a control (Tbx21::Ai9) mice. ( B ) Example of membrane potential traces recorded from one M/T cells expressing Kir, with the same stimuli as in A. ( C–D ) Resting membrane potential ( C ) and input resistance ( D ) of M/T cells in control (Tbx21::Ai9) mice (n=14 in C and n=19 in D), Kir-negative cells MCs in Tbx21 mice injected with Kir virus (Kir- control; n=8 in C and n=8 in D), or Kirexpressing MCs (Kir+; n=21 in C and n=17 in D). ( E ) F-I (firing frequency/injected current) curve of control and Kir +MCs. Figure 3—figure supplement 3—source data 1. Overexpressing the Kir2.1 channel reduces M/T cell activity.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Membrane, Control, Expressing, Injection, Virus, Activity Assay

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Schematic representation of the transgenic strategy to perform cell ablation in early postnatal (Tbx21::DTA) and adult (Tbx21::iDTR) mice to analyze the axon projection of the M72 olfactory sensory neurons into the OB. ( B ) Two possible scenarios are expected for the OSN axon projection to the OB after M/T cells ablation. (left) M72 OSN axon project to a single glomerulus per hemibulb as in wt animals, or (right) M72 OSN axons project to more than one glomeruli per hemibulb, perturbing the odor map in the OB surface. ( C ) Confocal images of M72 OSN axons (green) in a wild type mouse (Tbx21, top row) and Tbx21::DTA mice (bottom row). Each column represents the analysis of the OSN axon at two different time points ( P10 and P21 ). Immunostaining against olfactory marker protein (OMP, red) labels all OSN axons. Blue = DAPI staining. ( E ) Confocal images of M72 OSN axons (green) in Tbx21, Tbx21::DTA and Tbx21::iDTR mice at P120. The glomerular projection was disrupted in adult mice, both in animals in which ablation occurred soon after birth (Tbx21::DTA) or as adults (Tbx21::iDTR injected at P60 with DT). Immunostaining against OMP (red) labels all OSN axons. Blue = DAPI staining. Scale bar in D is 50 µm and applies to ( A-D ). ( F ) Percentage of M72 OSN axons projecting to one, two, three or more glomeruli per hemibulb in Tbx21, Tbx21::DTA and Tbx21::iDTR mice. No differences were observed at P10 and P21 between the M72 OSN axon in normal conditions or with reduced M/T cells Tbx21: P10 (n=12), P21 (n=20); Tbx21::iDTR: P10 (n=12), P21 (n=12). At P10 (p-value = 0.59; χ2 test), P21 (p-value = 0.23). However, significant differences in M72 OSN axons were observed in Tbx21::DTA (n=64; p-value <0.001) and Tbx21::iDTR (n=52; p-value <0.001) mice at P120, projecting to multiple glomeruli instead of a single glomerulus as in Tbx21 mouse (n=24). Figure 4—source data 1. Disruption of the odor map after M/T cell ablation.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Transgenic Assay, Immunostaining, Marker, Staining, Injection, Disruption

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: ( A ) Olfactory performance of Tbx21 (n=12), Tbx21::DTA (n=13), and Tbx21::iDTR (n=11) mice in a go/no go paradigm to investigate their odor detection ability. Decreasing cineole concentrations were presented each experimental day. Dots represent the mean percentage of accuracy responses in a single day. Accuracy lower than 80% was considered as a deficit in olfactory detection. Tbx21::DTA and Tbx21::iDTR mice successfully performed odor detection with concentrations of cineole as low as 0.05%, but failed when the concentration of odorant was further reduced. Control mice (Tbx21) successfully detected cineole at all concentrations tested (up to 0.001%). ( B ) Odor discrimination experiment exposing mice to increasing binary mixtures of cineole and eugenol (left) and (+)-carvone and (−)-carvone odors (right). Both experimental mice (Tbx21::DTA and Tbx21::iDTR) could successfully detect cineole and eugenol when they were presented as individual odors, or with 80/20 mixtures. However, they failed when mixtures of cineole::eugenol were 55/45. However, Tbx21::iDTR mice discriminated between (+)-carvone and (−)-carvone odors presented individually, but not when odor mixtures were presented. Tbx21::DTA could not discriminate between (+)-carvone and (−)-carvone even when they were presented as individual odors. ( C ) Tbx21::DTA and Tbx21::iDTR males mated with wt females with a much lower frequency (Tbx21::DTA = 16.67%; n=12; and Tbx21::iDTR = 63.63%; n=11) compared to control males (90.91%; n=11). ( D ) In a resident/intruder paradigm, then the resident and intruder were both wt male mice, the resident started a fight in >90% of the tests. When the resident was a wild type male they fought in 33.33% of the cases if the intruder was a Tbx21::DTA male (n=9) or 28,57% if the intruder was a Tbx21::iDTR male (n=7). When the residents were Tbx21::DTA (early postnatal cell ablation) or Tbx21::iDTR (cell ablation at P60) males, they did not fight when the intruder was a male with the same genotype or a wild type male mouse. ( E ) Quantification of M/T cells in the accessory olfactory bulb (AOB) in Tbx21, Tbx21::DTA, and Tbx21::iDTR showed that only 1.6% of M/T cells remained (29.4±13.7, average ± S.E.M.; n=5) in Tbx21::DTA mice and 16,6% in Tbx21::iDTR (315.3±50; n=3) compared to control Tbx21 mice (1900±168.4; n=3). Figure 5—source data 1. Reduction of M/T cell numbers affects mouse behavior.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: Concentration Assay, Control

Journal: eLife

Article Title: Projection neurons are necessary for the maintenance of the mouse olfactory circuit

doi: 10.7554/eLife.90296

Figure Lengend Snippet: The Tbx21::iDTR mice (n=14) could be grouped in three different groups depending on the type of behavior that they exhibited in the go/no go paradigm for olfactory detection. Group 1: 50% of the mice (n=7) performed the test accurately from the first day [black line]; Group 2: 29% (n=4) were able to perform the task after one week of training [dark grey line], and Group3: 21% of the mice (n=3) were unable to do the test even after several weeks of training [stippled gray line]. Dots represent the mean percentage of accuracy responses in a single day. Accuracy lower than 80% was considered as a deficit in odor detection. Figure 5—figure supplement 1—source data 1. Odor detection accuracy after M/T cells depletion in adult mice.

Article Snippet: The reporter mouse DTA (JAX#009669) expresses the subunit A of the diphtheria toxin upon cre recombination , inducing death of M/T cells at early postnatal stages when crossed with Tbx21 Cre mouse .

Techniques: