A brain-wide analysis maps structural evolution to distinct anatomical module

  1. Robert A Kozol  Is a corresponding author
  2. Andrew J Conith
  3. Anders Yuiska
  4. Alexia Cree-Newman
  5. Bernadeth Tolentino
  6. Kasey Benesh
  7. Alexandra Paz
  8. Evan Lloyd
  9. Johanna E Kowalko
  10. Alex C Keene
  11. Craig Albertson
  12. Erik R Duboue  Is a corresponding author
  1. Jupiter Life Science Initiative, Florida Atlantic University, United States
  2. Department of Biology, University of Massachusetts Amherst, United States
  3. Department of Biology, Texas A&M University, United States
  4. Department of Biological Sciences, Lehigh University, United States
5 figures, 1 table and 3 additional files

Figures

Figure 1 with 3 supplements
Developing a single A. mexicanus atlas to perform direct brain-wide morphometric analyses across all populations.

(a) Map showing the 29 independently evolved cave populations (black dots) of the El Abra region in Mexico. The Pachón cavefish population used for this project is marked as a red dot. Scale bars = …

Figure 1—source data 1

Surface × Pachón F2 hybrid brain atlas in nifty format.

Whole-brain segmented z-stack that outlines 180 defined brain regions. Z-projections of atlas stack were used to generate images.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig1-data1-v2.zip
Figure 1—figure supplement 1
Pipeline for immunohistochemistry, automated segmentation, and volumetric comparisons of individual fish larvae.

(a) Larval fish were imaged at 5 dpf to measure external anatomical features (e.g. standard length). (b) Larvae were fixed at 6 dpf, immunostained with total-ERK (tERK) and imaged on a two-photon …

Figure 1—figure supplement 2
Cross-correlation analysis between hand and automated segmentation of total-ERK-defined brain segments.

(a) Optical sections (coronal) through the and optic tectum (white matter light blue and gray matter red) and pallium (dark blue). Hand segmentations are in color, while automated versions are shown …

Figure 1—figure supplement 3
RNA probe and antibody analysis of segmentation accuracy across the Astyanax atlas.

Segmentation of (a) otx2 positive neurons in the optic tectum, (b) gbx1 neurons in the subpallium, (c) nos1 neurons in the thalamus, (d) oxt positive neurons in the medial preoptic regions, (e) …

Figure 2 with 1 supplement
Volumetric variation in wildtype populations reveal convergent dorsal contraction and ventral expansion in the brain of two cavefish populations.

(a) Volumetric comparison of the diencephalon in surface fish, Pachón and Molino cavefish. Percent total brain volume represents pixels of segment divided by total pixels in the brain. Sagittal …

Figure 2—source data 1

Volumetric values for the diencephalon of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data1-v2.zip
Figure 2—source data 2

Volumetric values for the dorsal diencephalon of wilid-type larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data2-v2.zip
Figure 2—source data 3

Volumetric values for the habenula of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data3-v2.zip
Figure 2—source data 4

Volumetric values for the ventral thalamus of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data4-v2.zip
Figure 2—source data 5

Volumetric values for the dorsal thalamus of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data5-v2.zip
Figure 2—source data 6

Volumetric values for the hypothalamus of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data6-v2.zip
Figure 2—source data 7

Volumetric values for the preoptic region of wildtype larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data7-v2.zip
Figure 2—source data 8

Volumetric values for the intermediate zone of wildtype individual larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data8-v2.zip
Figure 2—source data 9

Volumetric values for the caudal hypothalamus of wildtype individual larvae.

Three columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig2-data9-v2.zip
Figure 2—figure supplement 1
Variation in segment volume between surface and cavefish populations.

(a) Major brain divisions of the vertebrate brain and box plots comparing the volume of each region between surface and cave. Volumes are reported as percentage of total brain volume, calculated by …

Figure 3 with 2 supplements
Scalable segmentation of the tectum identifies high variability in the ventral sub-nuclei of the optic tectum’s cell layers.

(a) Volumetric comparison of the mesencephalon in surface fish, Pachón cavefish, Molino cavefish, surface × Pachón F2 hybrid (SPF2), and surface × Molino F2 hybrid (SMF2) larvae. Sagittal sections …

Figure 3—source data 1

Volumetric values for the mesencephalon of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data1-v2.zip
Figure 3—source data 2

Volumetric values for the tegmentum of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data2-v2.zip
Figure 3—source data 3

Volumetric values for the optic tectum of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data3-v2.zip
Figure 3—source data 4

Volumetric values for the optic tectum gray matter of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data4-v2.zip
Figure 3—source data 5

Volumetric values for the optic tectum white matter of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data5-v2.zip
Figure 3—source data 6

Volumetric values for the rostral optic tectum of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data6-v2.zip
Figure 3—source data 7

Volumetric values for the dorsal optic tectum of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data7-v2.zip
Figure 3—source data 8

Volumetric values for the ventral optic tectum of wildtype and F2 hybrid larvae.

Five columns of normalized volumetric values for wildtype surface, Pachón and Molino cavefish, and F2 surface × cave populations. Populations were analyzed via one-way ANOVA.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig3-data8-v2.zip
Figure 3—figure supplement 1
Volumetric variability in hybrid larvae reflects wildtype genetic diversity through dominant and intermediate phenotypes.

Representative regions for hybrid larvae that show (a) an intermediate brain size between wildtype surface and cave values, (b) genetic dominance with Pachón cavefish (dorsal diencephalon) or …

Figure 3—figure supplement 2
Hybrid brains link genetic variation in wildtype populations to anatomical variation in distinct sub-nuclei of the olfactory bulb, subpallium, and pallium.

(a) Volumetric comparison of the telencephalon in surface fish, Pachón cavefish, Molino cavefish, and surface × cave F2 hybrids. Percent total brain volume represents pixels of segment divided by …

Figure 4 with 1 supplement
Volumetric covariation and clustering of hybrid brain regions reveals convergent associations across the dorsal-ventral axis.

(a) Cross-correlation analysis of surface to Pachón F2 hybrids for the 180 segmented Astyanax brain atlas. (b) Cluster analysis array showing six clusters exhibiting positive volumetric …

Figure 4—source data 1

Correlation coefficient matrix for 180-brain region atlas volumetric comparisons of surface × Pachón F2 hybrid larvae.

Pairwise correlation coefficients for pairwise comparisons between each brain region within the F2 population. Each individual coefficient represents the relationship between two individual brain regions within the F2 population.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig4-data1-v2.zip
Figure 4—source data 2

Correlation coefficient matrix for 180-brain region atlas volumetric covariation of surface × Molino F2 hybrid larvae.

Pairwise correlation coefficients for pairwise comparisons between each brain region within the F2 population. Each individual coefficient represents the relationship between two individual brain regions within the F2 population.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig4-data2-v2.zip
Figure 4—figure supplement 1
Covariation of brain region size reveals developmental tradeoff between dorsal-ventral clusters brain-wide in independently derived cavefish populations.

(a) Pairwise correlation and (b) clustering matrices comparing covariation for surface to Pachón F2 hybrids between 13 brain segments. (c) Illustrations depicting clustered segments: cluster 1 …

Figure 5 with 6 supplements
Shape covariation suggests volume and shape share brain-wide mechanism of brain evolution.

Representatives of shape for the cerebellum and hypothalamus of pure populations (a) principal component 1 (PC1) and (b) principal component 2 (PC2). (c) Correlation matrix comparing the covariation …

Figure 5—source data 1

Correlation coefficient matrix for 13 brain region atlas shape covariation of surface × Pachón F2 hybrid larvae.

Each individual coefficient represents the relationship between two individual brain regions within the F2 population.

https://cdn.elifesciences.org/articles/80777/elife-80777-fig5-data1-v2.zip
Figure 5—figure supplement 1
Shape variability of the preoptic region in hybrid larvae display an intermediate phenotype between wildtype populations.

(a) Principal component analysis (PCA) capturing 54% of the variation across surface, cave, and surface × cave F2 hybrids. PC1 describes preoptic width, while PC2 describes length. (b) Illustrations …

Figure 5—figure supplement 2
Pineal shape variation in hybrids exhibits a cavefish dominant phenotype.

(a) Principal component analysis (PCA) capturing 50% of the variation across surface, cave, and surface × cave F2 hybrids. PC1 describes pineal length, while PC2 describes pineal width across …

Figure 5—figure supplement 3
Optic tectum shape variation is characterized by width curvature and thickness.

(a) Principal component analysis (PCA) capturing 52% of the variation across surface × cave F2 hybrid optic tectums. PC1 describes optic tectum curvature and length (b), while PC2 describes optic …

Figure 5—figure supplement 4
Cerebellar shape variation is characterized by depth of curvature and thickness.

(a) Principal component analysis (PCA) capturing 39% of the variation across surface × cave F2 hybrid cerebellums. PC1 describes cerebellar curvature and length (b), while PC2 describes cerebellar …

Figure 5—figure supplement 5
Hypothalamic shape variation is characterized by length, central thickness, and posterior width.

(a) Principal component analysis (PCA) capturing 39% of the variation across surface × cave F2 hybrid hypothalamus. PC1 describes hypothalamic length and center depth (b), while PC2 describes …

Figure 5—figure supplement 6
Tegmentum shape variation is characterized by depth and length.

(a) Principal component analysis (PCA) capturing 30% of the variation across surface × cave F2 hybrid tegmentums. PC1 describes tegmental length and center depth (b), while PC2 describes tegmental …

Tables

Table 1
Hybridization chain reaction (HCR) in situ hybridization probes.
GeneA. mexicanuspopulationEnsembl IDMolecular Instruments Lot #
gbx1SurfaceENSAMXT00000037099.1PRO705
gbx1PachónENSAMXT00005023309.1PRO706
otx2bSurfaceENSAMXT00000055482.1PRQ451
otx2bPachónENSAMXT00005060650.1PRQ452
oxtSurfaceENSAMXT00000041101.1PRQ449
oxtPachónENSAMXT00005006990.1PRQ450

Additional files

MDAR checklist
https://cdn.elifesciences.org/articles/80777/elife-80777-mdarchecklist1-v2.docx
Source code 1

README.md file that includes text describing the material in Source code 2, a repository of scripts used in this study.

https://cdn.elifesciences.org/articles/80777/elife-80777-code1-v2.zip
Source code 2

Kozol et al. Code.zip file containing bash (.sh), fiji (.ijm), and matlab (.m) files used for this study.

https://cdn.elifesciences.org/articles/80777/elife-80777-code2-v2.zip

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