Figure 5.

LAM inhibits retrotransposon expression by maintaining heterochromatin. (A) A cartoon illustration of the third instar larvae. Fat body (orange) aligns the inner cuticle surface of most of the larval body. The mouth hook (black) and salivary gland (blue) are also shown. (B–E) RPKM (Reads Per Kilobase per Million mapped reads) values of RNA expression, H3K4me3, and H3K9me3 modification for the indicated two retrotransposons (BLASTOPIA and Invader4) in the wild‐type and Lam ^−/− (Lam ^D395 /Lam ^k2) third instar fat bodies. Increased retrotransposon expression was accompanied by decreased H3K9me3 and increased H3K4me3 modifications. (F) Chromatin immunoprecipitation (ChIP)‐qPCR analysis of selected retrotransposons (BLASTOPIA and Invader4) of fat body dissected from the 5‐day or 50‐day wild‐type (w ¹¹¹⁸), or 5‐day Lam ^−/− (Lam ^D395 /Lam ^k2) flies. Chromatin was immunoprecipitated with antibodies to H3K4me3, H3K9me3, or control IgG. Primers corresponding to BLASTOPIA, Invader4, and rp49 (control) were used to amplify precipitated DNA. ChIP samples were normalized to the input DNA. Error bars, SEM, based on three independent experiments. Student's t‐tests: ^P > 0.05, *P < 0.05, **P < 0.01.