Recombinant amino-terminal (rF16)(a) and carboxy-terminal (rF6H)(b) halves of human fibrillin-1 were analyzed by electron microscopy after rotary shadowing. Representative images and histrograms of the measured lenghs of the recombinant fragments are shown. Note that both fragments showed thread-like extended molecules. The measurements are plotted as number of measurements, in 5 nm windows. The average length of rF16 was 73.1 ± 5.7 nm (mean ± SD; n = 75) and the average length of rF6H was 64.2 ± 5.9 nm (mean ± SD; n = 56).