Model Organisms in Drug Discovery

LIPID METABOLISM SCREEN 209
Figure 8.2 Labeling with BODIPY FR-PC. (A) The structure of BODIPY FR-PC. When
the molecule is intact in the cell, excitation at 505 nm results in orange (568 nm) emission
due to fluorescence resonance energy transfer (FRET) between the two BODIPY-labeled
moieties. Upon PLA 2 cleavage at the sn-2 position, the BODIPY moiety at the sn-1
position results in green (515 nm) emission when excited (505 nm). (B) BODIPY FR-PC
(5 mg/ml)-labeled zebrafish larva 5 days post-fertilization. The liver (L) and gall bladder
(GB) showed green fluorescence (green arrow), indicating the accumulation of cleaved
products. Uncleaved orange BODIPY FR-PC (orange arrow) is observed only in the
intestinal epithelium (IE)
is profoundly attenuated in a similar manner to that observed in fat-free
larvae (Farber et al., 2001). Addition of exogenous fish bile reversed the
blocking effect of Lipitor, suggesting that Lipitor blocks the synthesis of the
cholesterol-derived biliary emulsifiers that are required for lipid absorption.
However, the effect of Lipitor on NBD-cholesterol processing in wild-type
larvae was slightly different from that observed in fat-free mutant larvae.
Wild-type larvae had markedly reduced NBD-cholesterol fluorescence in the
intestinal lumen following Lipitor treatment but gall bladder fluorescence was
preserved (Figure 8.3A). In contrast, fat-free failed to accumulate NBDcholesterol
either in the intestine or in the gall bladder (Figure 8.3B). The