Fig. 5

pT172Ab immunoreactivity in various regions of P1 marmoset brain. a pT172Ab immunoreactivity was detected in mid- and hind-brain together with hematoxylin counterstain. b and c Immunohistochemistry for pons (b) and cerebellum (c), respectively, using Abs against GAP-43, pT172, synaptophysin, and pJNK. Hematoxylin stained the neuronal nuclei as blue. Compared to GAP-43 itself and the synaptophysin Ab, pT172Ab immunoreactivity was selectively detected in the growing axons, not in the cell bodies. Phosphorylated JNK, its activated form, was colocalized with pT172Ab immunoreactivity in this tissue. Higher magnification images using pT172 (c’) and synaptophysin (c’’) Abs are shown from boxes in (c). pT172Ab immunoreactivity was not detected within Purkinje cells. SC superior colliculus; IC inferior colliculus; MVeN medial vestibular nucleus; Pn pontine nuclei. Primary fissures are noted with an arrow. Scale bar: 2000 μm in (a) and 200 μm in (b) and (c). EGL external molecular layer; IGL internal granule layer; PCL Purkinje cell layer; and MF mossy fiber. d pT172Ab immunoreactivity of the brain stem area and its enlargement (e). pT172Ab recognized in the elongating lateral corticospinal tract, which is also NF-M Ab stained. CC central canal; CuF cuneate fasciculus; GrF gracile fasciculus; LCF lateral corticospinal fiber; and StT spinal trigeminal tract. f pT172Ab immunoreactivity in the visual cortex. Cal calcarine sulcus; DA dorsoanterior extrastriate area; DM dorsomedial visual area; POm parietooccipital medial area; V1 primary visual cortex; VLA ventriolateral anterior extrastriate area; and VLP ventriolateral posterior extrastriate area. Scale bar: 2000 μm. g Higher magnification images of box in (f). I-VI, the cortical layer numbers. pT172Ab immunoreactivity was observed in layers IVb and V. h Counterstaining using Nissl staining and pT172Ab. Because Nissl staining features the neuronal cell bodies, it suggests that pT172Ab immunoreactivity was not present there. Reference staining views in the adjacent sections are also shown as the immunoreactivity of (i) GAP-43Ab itself, j NF Ab, and k synaptophysin Ab (counterstained with hematoxylin). Scale bar: 200 μm (g–k). l pT172Ab immunoreactivity in the frontal cortex. Scale bar: 2000 µm. CA cornu ammonis; CC corpus callosum; DG dentate gyrus; Er entorhinal cortex; f fornix; LV lateral ventricle; LPul lateral pulvinar; Sub: subiculum; 3 V: 3rd ventricle. m, n Higher magnification images of the box in (l). Scale bar: 200 µm. o Immunoblotting of several different regions of P1 marmoset brain using pT172Ab. GAPDH and β-actin: positive controls. Arrowheads: predicted bands. Note that the immunoreactivity of pJNKAb is generally associated with that of pT172Ab. FCx frontal cortex; VCx visual cortex; Cbll cerebellum; Mid-brain midbrain tissue partially containing pons. p Shotgun phosphoproteomics of a 50-kDa-level gel sample (see Additional file 7: Fig. S6c) of the P1 marmoset brain (midbrain containing pons) for GAP-43 phosphorylation sites. The detected phosphorylated peptides are shown in italic and bold letters