Supplemental Table I

Transcription

1 Supplemental Table I Cortex Hippocampus Age (weeks) Genotype STE 61 pste 61 STE 61 pste ± ± ± ± 7.8* ± ± ± ± 33.9** ± ± 7.7* 99.9 ± ± 0.1* ± ± ± ± 16.4** ± ± 5.3*** 99.8 ± ± 23.8*** ± ± ± ± 131.3* Supplemental Table I. STE protein expression and phosphorylation levels in the cortex and hippocampus of mice at different ages. STE 61 and pste 61 levels were analyzed by Western blot of protein extracts obtained from the cortex and hippocampus of wild-type () and mice at different stages of the disease progression. Values (obtained by densitometric analysis of Western blot data) are expressed as percentage of mice (STE 61 /α-tubulin or pste 61 /STE 61 ratio after normalization with α-tubulin), and shown as mean ± SEM (n = 5-8). Data were analyzed by Student s t test. * < 0.05; ** < 0.01 and *** < as compared with mice.

2 Supplemental Figure 1 1 h after QUIN injection 4 h after QUIN injection + QUIN + QUIN STE levels (% contralateral) STE levels (% contralateral) STE 61 STE 33 0 STE 61 STE 33 Supplemental Figure 1. Absence of STE 61 cleavage to STE 33 after intrastriatal QUIN injection. STE 61 and STE 33 levels were analyzed by Western blot of protein extracts obtained from the striatum of 12-week old wild-type () and mice 1 and 4 h after an intrastriatal injection of vehicle or QUIN (10 nmol). Values (obtained by densitometric analysis of Western blot data) are expressed as percentage of the contralateral vehicle-injected striatum (STE 61 /α-tubulin and STE 33 /α-tubulin ratio, respectively), and data shown are the mean ± SEM (n = 6-9). : vehicle-injected striatum; + QUIN: QUIN-injected striatum; : vehicle-injected striatum; + QUIN: QUIN-injected striatum.

3 Supplemental Figure 2 A TAT-myc TAT-STE BS QUIN (10 or 20 nmol) erfusion 1 h 24 h myc immunohistochemistry Fluoro-Jade staining myc/p immunohistochemistry B C BS TAT-STE Supplemental Figure 2. Characterization of TAT-STE intrastriatal injection. (A) Schematic design of the experiments with TAT-peptides. (B) TAT-STE was injected in the striatum of mice and immunohistochemical staining with anti-myc antibody was performed 1 h after injection. Representative image showing myc immunoreactivity in individual cells. Scale bar, 40 µm. (C) To analyze the possible toxic effect of TAT-STE, it was injected in wild-type mice striatum 1 h before vehicle (BS) injection. Fluoro-Jade staining was performed 24 h after intrastriatal BS injection to assess cell death. Images showing absence of cell death in the striatum of mice injected with BS or TAT-STE plus BS. Scale bar, 500 µm.

4 Supplemental Figure 3 A B TAT-myc + QUIN TAT-STE + QUIN a1 a2 Volume of the lesion (% TAT-myc + QUIN) TAT-myc +QUIN * TAT-STE +QUIN C TAT-myc + QUIN TAT-STE + QUIN myc p myc p Lesioned area Lesioned area c1 c2 c5 c6 c3 c4 c7 c8

5 Supplemental Fig. 3. Intrastriatal TAT-STE injection increases QUIN-induced cell death in wild-type mice. Control peptide (TAT-myc) or TAT-STE was intrastriatally injected in wild-type mice 1 h before intrastriatal QUIN injection. Fluoro-Jade staining and immunohistochemistry against myc and p were performed 24 h after QUIN injection. (A) Representative photomicrographs show the striatal area occupied by Fluoro-Jadepositive cells in wild-type mice striatum injected with TAT-myc plus QUIN (a1) or TAT- STE plus QUIN (a2). (B) Graph shows the quantification of the volume of the lesion measured in Fluoro-Jade stained sections and expressed as a percentage of TAT-myc + QUIN-injected mice. * < 0.05 as compared with TAT-myc + QUIN-injected striatum. (C) Representative photomicrographs showing myc (c1, c3, c5 and c7) and p (c2, c4, c6 and c8) staining in TAT-myc + QUIN (c1-c4) and TAT-STE + QUIN (c5-c8)-injected striatum. Note that p was not detected in cells positive for myc in TAT-STE + QUIN-injected striatum. Scale bar (A) 500 µm, (c1, c2, c5 and c6) 100 µm and (c3, c4, c7 and c8) 30 µm.

6 Supplemental Figure 4 Wild-type striatum A D1R NMDAR KA STE (inactive) STE (active) Calcineurin STE mrna striatum (early stages) B D1R NMDAR KA STE (inactive) STE (active) Calcineurin mhtt STE mrna striatum (late stages) C D1R KA mhtt STE mrna STE (inactive) STE (active) Calcineurin mhtt NMDAR

7 Supplemental Figure 4. Regulation of STE expression and activity in mice striatum. In the absence of mhtt (A) stimulation of D1Rs by dopamine leads to KA activation and phosphorylation of STE that prevents STE from interacting with its substrates, such as ERK (aul et al., 2000). Stimulation of NMDA receptors by glutamate enables the activation of the serine/threonine phosphatase calcineurin, leading to dephosphorylation of the regulatory kinase interacting motif domain serine residue and consequent activation of STE (aul et al., 2003). The presence of mhtt in the striatum alters this system at different levels: early during disease progression (B) mhtt induces a down-regulation of STE mrna levels that results in decreased STE protein levels and a deregulation of the KA pathway that correlates with increased STE phosphorylation. Decreased STE protein levels and activity can participate in neuronal dysfunction. At late stages of the disease progression (C) mhtt reduces calcineurin activity, which further inactivates STE causing an increase in p levels (p-p38 levels and possibly other STE targets not analyzed in this study, which were omitted for simplicity). Decreased STE activity, through the regulation of its targets, could be involved in the development of resistance to excitotoxicity in mice striatum.