Supplementary information
Figure S1. IAP and MusD base mutation spectra induced by APOBEC3G in the cellbased retrotransposition assay. Mutations detected in one pol fragment of IAP (upper
panel) and two pol fragments of MusD (lower panels). 23 and 25 individual clones were
analyzed for IAP and MusD, respectively. Mutations generated by murine APOBEC3 (mA3)
and human APOBEC3G (hA3G) enzymes are depicted above and below the consensus line,
respectively. Color code: GA, red; non-GA, green. The two upper panels correspond to
the 700-bp sequences depicted in Fig. 2, but only the first 600-bp are shown. The mutation
spectra induced by mA3 on an additional 600-bp pol MusD fragment is depicted on the lower
panel.
Human APOBEC3G and murine APOBEC3 induce G-to-A hypermutations in the genome of
IAP and MusD retroelements, and target non-random deamination hotspots. Variations in the
editing profile of hA3G and mA3 strongly suggest that the preferential target DNA sequences
for the two enzymes are not identical.
Figure S2. Distibution of G-to-A hypermutations in MusD sequences found in the mouse
genome.
Five MusD endogenous sequences, selected from those analyzed in Fig. 3, were aligned with
the consensus sequence (C), in order to visualize subgenomic regions that have undergone Gto-A hypermutations. The five selected MusD sequences carry respectively 55, 47, 64, 74 and
58 G-to-A mutations occurring in the context of GXA trinucleotides (which are underlined in
the consensus sequence), Dots indicate identities. G-to-A substitutions are highlighted in red.
The two boxes correspond to the regions presented in Fig. 4b.
Numerous G-to-A mutations can be detected in sub-regions of individual MusD elements.
These mutations often occurred in the G(G/A)A context, consistent with the quantitative
analysis presented in Fig. 3 and 4.
The genomic location of these sequences, and of the sequences shown in Fig. 4b are as
follows: mmchr16 : mmchr16_0308 (77621 - 70146) ; mmchrX : mmchrX_1141 (13627 21121) ; mmchr13 : mmchr13_0050 (79688 - 87135) ; mmchr18(1) : mmchr18_0082 (83610
- 76192) ; mmchr11 : mmchr11_0491 (84922 - 92397) ; mmchr17 : mmchr17_0177 (9249 1840) ; mmchr9 : mmchr9_0119 (43468 - 50932) ; mmchr14 : mmchr14_0650 (65630 58148) ; mmchr7 : mmchr7_0959 (25691 - 18249) ; mmchr3 : mmchr3_0045 (10422 2843) ; mmchr5 : mmchr5_0587 (15706 - 8243) ; mmchr18(2) : mmchr18_0080 (25899 33309)