Scale bar = 200 mm; (B,C) High-magnification views of pulmo- nary alveoli. Scale bar = 40 mm. (TIF) Figure S9 Decrease of p21Cip1 (CDKN1A) mRNA in RASSF92/2 skin. Total RNA of mice skins were extracted by TRIzol reagent, and used to determine the mRNA level of p21Cip1 in mouse skin tissue by QRT-PCR using p21Cip1 gene- specific primers followed by normalization with regard to the mRNA expression of the reference gene: (A) b-Actin, (B) GAPDH and (C) HPRT1. Mean 6 SD (n = 3, per genotypes); *, P,0.05; +/ +, wild type; 2/2, RASSF92/2. (TIF) Figure S10 Expression profile of RASSF9 mRNA in normal mouse primary keratinocytes. Total RNA was prepared from mouse primary keratinocytes cultured for the indicated times in growth medium (0.06 mM calcium) or differentiation-inducing medium (2 mM calcium). RASSF9 mRNA expression was determined by QRT-PCR analysis using RASSF9 gene-specific primers followed by normalization with regard to the mRNA expression of the reference gene: (A) b-Actin, (B) GAPDH and (C) HPRT1. The results shown are given as the fold-change (Mean 6 SD, n = 3); * P,0.05; ** P,0.005. (TIF) Figure S11 RASSF9+/2 keratinocytes could be induced to differentiate in a manner similar to that of WT keratinocytes. keratinocytes from RASSF9-deficient heterozy- gotes or WT mice were cultured under growth (0.06 mM calcium) or differentiation-inducing (2 mM calcium) conditions for 4 days, and the expression levels of filaggrin (a marker for terminal differentiation) and K14 (loading control) were analyzed by Western blotting. Similar results were obtained in three indepen- dent experiments. +/+, wild type; +/2, RASSF9+/2. (TIF) Figure S12 RASSF9 expression could differentiation defects in RASSF92/2 overcome the keratinocytes, References 1. 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