Figure 1.
Schematic of the mouse OPRM1 gene structure, alternative splicing and predicted protein structures.
A, Genomic structure of the mouse OPRM1gene. Exons and introns are showed by boxes and horizontal lines, respectively. Intron size is indicated below the introns as kilobases (kb). Promoters are showed by arrows. Exons are numbered based upon the published data. B, Alternative splicing of C-terminal splice variants with 7-TM domains. Translational start and termination sites are indicated by downward and upward lines on exon boxes, respectively. The lines between exons are introns that are spliced out during splicing. Predicted receptor structures are inserted at the right with colored bars indicating different coding exons. C, Alternative splicing of truncated variants with 6-TM domains. D, Alternative splicing of truncated variants with 1-TM domain.
Figure 2.
Heatmap of expression levels of OPRM1 splice variant mRNAs.
The heatmap was generated by clustering Z-scores calculated from the values (Log2 (E−ΔC(t)) of individual variants across different strains/regions using R statistical language (2.15.0) (www.r-project.org), and plotting based upon expression levels among the variants with enhanced heatmap function heatmap.2 from gplots package. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. 129∶129P3/J; B6: C56BL/6J; SJL: SJL/J; SWR: SWR/J. Expression level was indicated by Z-score.
Figure 3.
Expression levels of selected ten splice variants in brain regions of four mouse strains.
Expression levels of (−1)/(Log2 (E−ΔC(t))) of selected variants is plotted across regions using MS excel. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. 129∶129P3/J; B6: C56BL/6J; SJL: SJL/J; SWR: SWR/J.
Figure 4.
Heatmap of regional expression OPRM1 splice variant mRNAs.
The heatmap was generated by clustering Z-scores calculated from the values (Log2 (E−ΔC(t)) of individual variants across different strains/regions using R statistical language (2.15.0) (www.r-project.org), and plotting based upon individual brain regions within each mouse strain with enhanced heatmap function heatmap.2 from gplots package. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. 129∶129P3/J; B6: C56BL/6J; SJL: SJL/J; SWR: SWR/J. Expression level was indicated by Z-score.
Figure 5.
Region-specific expressions of ten-selected OPRM1 splice variants.
Each panel represents the regional expression of one variant in four inbred mouse strains. Red bar: B6 mice; Green bar: 129 mice; Blue bar: SJL mice; Brown bar: SWR mice. Bars represent the mean of E−ΔC(t) values ± S.E.M. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. mE1-2 represents all full-length 7-TM variants. Significant difference was calculated by Two-way ANOVA with Tukey’s multiple comparisons test for each variant (Prism 5.0). The results of the statistical analysis were listed in Table S3. The expression profiles of the other 19 OPRM1 splice variants are shown in Figures S1 & S2.
Figure 6.
Heatmap of expression of OPRM1 splice variant mRNAs among four inbred mouse strains.
The heatmap was generated by clustering Z-scores calculated from the values (Log2 (E−ΔC(t)) of individual variants across different strains/regions using R statistical language (2.15.0) (www.r-project.org), and plotting based upon individual strains within each brain region with enhanced heatmap function heatmap.2 from gplots package. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. 129∶129P3/J; B6: C56BL/6J; SJL: SJL/J; SWR: SWR/J. Expression level was indicated by Z-score.
Figure 7.
Strain-specific expressions of OPRM1 splice variants.
Each panel represents the expression of one variant in 10 regions of 4 inbred mouse strains. Red bar: B6 mice; Green bar: 129 mice; Blue bar: SJL mice; Brown bar: SWR mice. Bars represent the mean of E−ΔC(t) values ± S.E.M. Pfc: prefrontal cortex; Str: striatum; Tha: thalamus; Hyp: hypothalamus; Hip: hippocampus; PAG: periaqueductal gray; BS: brainstem; Cb: cerebellum; Spc: spinal cord; WB: whole brain. Significant difference was calculated by Two-way ANOVA with Tukey’s multiple comparisons test for each variant. The results of the statistical analysis were listed in Table S3. The expression profiles of the other 19 OPRM1 splice variants are shown in Figures S3 & S4.