Influence of FHL-1 variants in expression of ceramide metabolism genes.

Abstract

(A) Schematic representation of CFH and FHL-1 proteins. CFH is composed of 20 short consensus repeats (SCR), and its alternative splicing variant FHL-1 of 7 SCR and a unique extension of 4 amino acids. The complement regulatory region (SCR 1–4), and surface recognition domains (SCR 19–20) are indicated. Residue 402 is located in the SCR 7 of both proteins. (B-G) WERI-Rb1 cells treated with 80 μg/mL BSA or MAA-BSA during 24 h with or without addition of 200 μg/mL CFH or 80 μg/mL FHL-1 proteins. Expression of genes from (B) NAD(P)H dehydrogenase [quinone] 1 (NQO1), (C) Phosphatidylcholine:ceramide cholinephosphotransferase 1 (SGMS1), (D) Serine palmitoyltransferase 1 (SPTLC1), (E) Sphingolipid delta(4)-desaturase DES1 (DEGS1), (F) Ceramide synthase 2 (CERS2), (G) Ceramide glucosyltransferase (UGCG). Each value corresponds to the mean ± SEM of four-fold independently performed experiments. Statistics: two-way blocked ANOVA and Tukey’s test (no significant interaction between principal effects was observed); (C-G) only the significance from the Tukey’s test comparing PBS, CFH, FHL-1:Y402 (Y), and FHL-1:H402 (H) are shown in the graphs; all genes showed significant differences between MAA-BSA and BSA treatments: (C, F) p<0.001, (G, E) p<0.01, (D) p<0.05. ***p<0.001, *p<0.05.</p