MRG proteins are shared by multiple protein complexes with distinct functions.

In this study, we characterized MORF4L1/MRG15 interactome. Using Flag-ChIP-sequencin K562 cells, we first claimed that both MRG15 isoforms (long or short chromodomain) and MORF4L2/MRGX which does not contain any chromodomain, shared mostly the same targets. Then, we described a new factor associated to MRG15, called EP400NL. EP400NL binds to BRD8 also linked to MRGBP and MRG15/X to form a new complex homolog to the yeast TINTIN. Using RNA-sequencing in BRD8 or MRGBP or MRG15/MRGX and KAT5/TIP60-depleted U2OS cells, we observed that human TINTIN plays a role in gene expression regulation independently of NuA4/TIP60 complex. Overall design: ChIP-sequencing of FLAG versus IgG in K562 cells expressing FLAG tagged MRG15 long CHD, MRG15 short CHD and MRGX protein. RNA-sequencing in U2OS cells after knockdown of MRG15 or MRGX or BRD8 or MRGBP or KAT5/TIP60. siLuciferase was used as control.