@article{Ilik_Maticzka_Georgiev-mutua_exclu_stem-2017,
author = {Ilik, Ibrahim Avsar and Maticzka, Daniel and Georgiev, 
          Plamen and Gutierrez, Noel Marie and Backofen, Rolf and 
          Akhtar, Asifa},
title = {A mutually exclusive stem-loop arrangement in {roX2} {RNA} 
         is essential for {X}-chromosome regulation in {Drosophila}},
journal = {Genes Dev},
year = {2017},
doi = {10.1101/gad.304600.117},
volume = {31},
user = {maticzkd},
pmid = {29066499},
pages = {1973-1987},
number = {19},
issn = {0890-9369},
abstract = {The X chromosome provides an ideal model system to study 
            the contribution of RNA-protein interactions in epigenetic 
            regulation. In male flies, roX long noncoding RNAs (lncRNAs) 
            harbor several redundant domains to interact with the 
            ubiquitin ligase male-specific lethal 2 (MSL2) and the RNA 
            helicase Maleless (MLE) for X-chromosomal regulation. 
            However, how these interactions provide the mechanics of 
            spreading remains unknown. By using the uvCLAP (UV 
            cross-linking and affinity purification) methodology, which 
            provides unprecedented information about RNA secondary 
            structures in vivo, we identified the minimal functional 
            unit of roX2 RNA. By using wild-type and various MLE mutant 
            derivatives, including a catalytically inactive MLE 
            derivative, MLE(GET), we show that the minimal roX RNA 
            contains two mutually exclusive stem-loops that exist in a 
            peculiar structural arrangement: When one stem-loop is 
            unwound by MLE, an alternate structure can form, likely 
            trapping MLE in this perpetually structured region. We show 
            that this functional unit is necessary for dosage 
            compensation, as mutations that disrupt this formation lead 
            to male lethality. Thus, we propose that roX2 lncRNA 
            contains an MLE-dependent affinity switch to enable 
            reversible interactions of the MSL complex to allow dosage 
            compensation of the X chromosome.}
}