Supplemental Figure 1: The S147G mutation does not lead to increased RII subunits - its main effect is through lack of binding to the catalytic subunit (Ca).

Ratio of R1a Expression to Type II Subunits Expression

R1alpha exp (R2alpha + R2beta exp)

±SE

2.50

NS

2.00

Met1Val, Ser9Asn, Arg74Cys, Arg146Ser, Ser147Cys, Asp183Tyr

1.50

1.00

Ala213Asp, Gly289Trp, Exon 3 skip

0.50

*

T

I

0.00

Abs R2b Exp < WT Abs R2b Exp

Abs R2b Exp > WT Abs R2b Exp

WT