Limits...
Clonal relationships impact neuronal tuning within a phylogenetically ancient vertebrate brain structure.

Muldal AM, Lillicrap TP, Richards BA, Akerman CJ - Curr. Biol. (2014)

Bottom Line: To address this question, we examined the influence of lineage on the response properties of neurons within the optic tectum, a visual brain area found in all vertebrates.If lineage relationships do not influence the functional properties of tectal neurons, one prediction is that the RF positions of sister neurons should be no more (or less) similar to one another than those of neighboring control neurons.Our data reveal that the RF centers of sister neurons are significantly more similar than would be expected by chance.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.

Show MeSH

Related in: MedlinePlus

Lineage Tracing of Individual Tectal Progenitor Cells(A) Schematic dorsal view of a tadpole’s head (top) illustrating the positions of the two optic tecta (shaded); epifluorescence image (bottom) showing the electroporation of a single tectal progenitor cell with a fluorescently conjugated dextran (red). Region corresponds to dashed box above. ven, ventricle; pz, proliferative zone; ncb, neuronal cell bodies.(B) Two-photon image showing a single tectal progenitor cell captured 2 hr postelectroporation. The scale bar represents 50 μm.(C) Image of a tectal clone consisting of one radial progenitor cell (solid arrowhead) and two daughter neurons (open arrowheads), collected 10 days postelectroporation. The scale bar represents 50 μm.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4151134&req=5

fig1: Lineage Tracing of Individual Tectal Progenitor Cells(A) Schematic dorsal view of a tadpole’s head (top) illustrating the positions of the two optic tecta (shaded); epifluorescence image (bottom) showing the electroporation of a single tectal progenitor cell with a fluorescently conjugated dextran (red). Region corresponds to dashed box above. ven, ventricle; pz, proliferative zone; ncb, neuronal cell bodies.(B) Two-photon image showing a single tectal progenitor cell captured 2 hr postelectroporation. The scale bar represents 50 μm.(C) Image of a tectal clone consisting of one radial progenitor cell (solid arrowhead) and two daughter neurons (open arrowheads), collected 10 days postelectroporation. The scale bar represents 50 μm.

Mentions: To examine whether lineage-based rules contribute to functional circuit organization in the optic tectum, we developed a method for labeling a single neuronal clone per animal, which enabled us to definitively identify sister tectal neurons. All animal procedures were conducted in accordance with UK Home Office regulations. Individual tectal progenitor cells in the proliferative zone [8] of stage 44–47 Xenopus laevis tadpoles (7–16 days postfertilization) were targeted for single-cell electroporation with a dextran-conjugated red fluorescent dye (Figure 1A; Supplemental Experimental Procedures available online) [9]. This dye does not leak out of cells and is only passed on to daughter cells [10, 11]. To ensure that a single neuronal clone was labeled, we conducted in vivo two-photon imaging at different time points. The first imaging was conducted 1–3 hr after electroporation to be certain that only one progenitor had taken up the dextran (Figure 1B). From a total of 438 animals in which we confirmed that a single progenitor cell was labeled, 103 contained two or more labeled sister neurons when the animal was reimaged 6–19 days later at stage 49 or 50 (Figure 1C).


Clonal relationships impact neuronal tuning within a phylogenetically ancient vertebrate brain structure.

Muldal AM, Lillicrap TP, Richards BA, Akerman CJ - Curr. Biol. (2014)

Lineage Tracing of Individual Tectal Progenitor Cells(A) Schematic dorsal view of a tadpole’s head (top) illustrating the positions of the two optic tecta (shaded); epifluorescence image (bottom) showing the electroporation of a single tectal progenitor cell with a fluorescently conjugated dextran (red). Region corresponds to dashed box above. ven, ventricle; pz, proliferative zone; ncb, neuronal cell bodies.(B) Two-photon image showing a single tectal progenitor cell captured 2 hr postelectroporation. The scale bar represents 50 μm.(C) Image of a tectal clone consisting of one radial progenitor cell (solid arrowhead) and two daughter neurons (open arrowheads), collected 10 days postelectroporation. The scale bar represents 50 μm.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4151134&req=5

fig1: Lineage Tracing of Individual Tectal Progenitor Cells(A) Schematic dorsal view of a tadpole’s head (top) illustrating the positions of the two optic tecta (shaded); epifluorescence image (bottom) showing the electroporation of a single tectal progenitor cell with a fluorescently conjugated dextran (red). Region corresponds to dashed box above. ven, ventricle; pz, proliferative zone; ncb, neuronal cell bodies.(B) Two-photon image showing a single tectal progenitor cell captured 2 hr postelectroporation. The scale bar represents 50 μm.(C) Image of a tectal clone consisting of one radial progenitor cell (solid arrowhead) and two daughter neurons (open arrowheads), collected 10 days postelectroporation. The scale bar represents 50 μm.
Mentions: To examine whether lineage-based rules contribute to functional circuit organization in the optic tectum, we developed a method for labeling a single neuronal clone per animal, which enabled us to definitively identify sister tectal neurons. All animal procedures were conducted in accordance with UK Home Office regulations. Individual tectal progenitor cells in the proliferative zone [8] of stage 44–47 Xenopus laevis tadpoles (7–16 days postfertilization) were targeted for single-cell electroporation with a dextran-conjugated red fluorescent dye (Figure 1A; Supplemental Experimental Procedures available online) [9]. This dye does not leak out of cells and is only passed on to daughter cells [10, 11]. To ensure that a single neuronal clone was labeled, we conducted in vivo two-photon imaging at different time points. The first imaging was conducted 1–3 hr after electroporation to be certain that only one progenitor had taken up the dextran (Figure 1B). From a total of 438 animals in which we confirmed that a single progenitor cell was labeled, 103 contained two or more labeled sister neurons when the animal was reimaged 6–19 days later at stage 49 or 50 (Figure 1C).

Bottom Line: To address this question, we examined the influence of lineage on the response properties of neurons within the optic tectum, a visual brain area found in all vertebrates.If lineage relationships do not influence the functional properties of tectal neurons, one prediction is that the RF positions of sister neurons should be no more (or less) similar to one another than those of neighboring control neurons.Our data reveal that the RF centers of sister neurons are significantly more similar than would be expected by chance.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.

Show MeSH
Related in: MedlinePlus