Histological findings in neurons and pancreas.

<p>(A) Swelling of neurons in the vestibular nucleus due to fine vesiculation (arrows) and clear vacuolization (arrowhead) of the cytoplasm. HE, scale bar 100 μm. (B) Clear cytoplasmic vacuolization (arrows) in cerebellar cortical Purkinje cells. HE, scale bar 100 μm. (C) Normal cerebellar cortex of an unaffected dog shows viable Purkinje cells (arrows) and a dense granular cell layer. HE, scale bar 100 μm. (D) Marked neuronal loss is present the cerebellar cortex of an affected dog. The number of neurons in the granular cell layer is reduced and only scattered Purkinje cells remain (arrow). HE, scale bar 100 μm. (E) Axonal spheroids of varying quality were seen in the white matter (arrows) of cerebellum and brainstem. HE, scale bar 100 μm. (F) Diffuse cytoplasmic vacuolization of the exocrine pancreatic acinar cells. HE, scale bar 100 μm. (G) Purkinje cell with numerous single-membrane bound, cytoplasmic vacuoles tethering to each other (arrows, inset). Electronmicrograph, scale bar 2 μm. Inset: scale bar 1 μm. (H) Axonal spheroid containing aggregated degenerated mitochondria, occasional double-membrane-bound autophagosomes (arrows) and free electron dense material, compressed by a peripheral clear vacuolar space. Electronmicrograph, scale bar 0.5 μm. Abbreviations: n, nucleus; ml, molecular layer; pl, Purkinje cell layer; gl, granular cell layer.</p

Variants detected by whole genome re-sequencing of an affected Lagotto Romagnolo.

<p>^aThe sequences were compared to the reference genome (CanFam 3.1) from a Boxer. Only those variants that were homozygous in the affected Lagotto Romagnolo are reported.</p><p>Variants detected by whole genome re-sequencing of an affected Lagotto Romagnolo.</p

Histological findings in neurons and pancreas.

<p>(A) Swelling of neurons in the vestibular nucleus due to fine vesiculation (arrows) and clear vacuolization (arrowhead) of the cytoplasm. HE, scale bar 100 μm. (B) Clear cytoplasmic vacuolization (arrows) in cerebellar cortical Purkinje cells. HE, scale bar 100 μm. (C) Normal cerebellar cortex of an unaffected dog shows viable Purkinje cells (arrows) and a dense granular cell layer. HE, scale bar 100 μm. (D) Marked neuronal loss is present the cerebellar cortex of an affected dog. The number of neurons in the granular cell layer is reduced and only scattered Purkinje cells remain (arrow). HE, scale bar 100 μm. (E) Axonal spheroids of varying quality were seen in the white matter (arrows) of cerebellum and brainstem. HE, scale bar 100 μm. (F) Diffuse cytoplasmic vacuolization of the exocrine pancreatic acinar cells. HE, scale bar 100 μm. (G) Purkinje cell with numerous single-membrane bound, cytoplasmic vacuoles tethering to each other (arrows, inset). Electronmicrograph, scale bar 2 μm. Inset: scale bar 1 μm. (H) Axonal spheroid containing aggregated degenerated mitochondria, occasional double-membrane-bound autophagosomes (arrows) and free electron dense material, compressed by a peripheral clear vacuolar space. Electronmicrograph, scale bar 0.5 μm. Abbreviations: n, nucleus; ml, molecular layer; pl, Purkinje cell layer; gl, granular cell layer.</p

Immunohistochemistry indicates disturbed autophagic flow in neurons.

<p>(A) Axonal spheroids stain diffusely positive for LC3B. IHC LC3B, scale bar 100 μm. (B,C) The granular cores of the spheroids are positive for (B) ubiquitin (arrow) and (C) p62. IHC ubiquitin and p62, scale bars 20 and 100 μm, respectively. (D) Smooth axonal swellings in the cerebellar cortex contain ATG4D. Inset: control. IHC ATG4D, scale bar 100 μm. (E) Affected neurons show increased perinuclear granular LC3B positivity. Inset: control. IHC LC3B, scale bar 100 μm. (F) Neuronal vacuoles are partially LAMP2 positive (arrow) and partially negative (arrow head). Inset: control. IHC LAMP2, scale bar 20 μm.</p