Tikhonova Evgeniya, Revel-Muroz Anastasia, Georgiev Pavel, Maksimenko Oksana
Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov Street, Moscow 119334, Russia.
Department of the Control of Genetic Processes, Institute of Gene Biology, Russian Academy of Sciences, 34/5 Vavilov Street, Moscow 119334, Russia.
Open Biol. 2024 Mar;14(3):230270. doi: 10.1098/rsob.230270. Epub 2024 Mar 13.
The male-specific lethal (MSL) complex binds to the male X chromosome to activate transcription. It comprises five proteins (MSL1, MSL2, MSL3, male absent on the first (MOF), and maleless (MLE)) and two long noncoding RNAs (lncRNAs; roX1 and roX2). The MLE helicase remodels the roX lncRNAs, enabling the lncRNA-mediated assembly of the dosage compensation complex. MSL2 is expressed only in males and interacts with the N-terminal zinc finger of the transcription factor chromatin-linked adapter for MSL proteins (CLAMP), which is important for the specific recruitment of the MSL complex to the male X chromosome. Here, we found that MLE's unstructured C-terminal region interacts with the sixth zinc-finger domain of CLAMP. , 4-5 zinc fingers are critical for the specific DNA-binding of CLAMP with GA repeats, which constitute the core motif at the high affinity binding sites for MSL proteins. Deleting the CLAMP binding region in MLE decreases the association of MSL proteins with the male X chromosome and increases male lethality. These results suggest that interactions of unstructured regions in MSL2 and MLE with CLAMP zinc finger domains are important for the specific recruitment of the MSL complex to the male X chromosome.
雄性特异性致死(MSL)复合物与雄性X染色体结合以激活转录。它由五种蛋白质(MSL1、MSL2、MSL3、雄性第一缺失蛋白(MOF)和无雄性蛋白(MLE))和两种长链非编码RNA(lncRNA;roX1和roX2)组成。MLE解旋酶重塑roX lncRNA,使lncRNA介导剂量补偿复合物的组装。MSL2仅在雄性中表达,并与MSL蛋白的转录因子染色质连接衔接子(CLAMP)的N端锌指相互作用,这对于MSL复合物特异性募集到雄性X染色体很重要。在这里,我们发现MLE的无结构C端区域与CLAMP的第六个锌指结构域相互作用。CLAMP与GA重复序列的特异性DNA结合需要4 - 5个锌指,GA重复序列构成了MSL蛋白高亲和力结合位点的核心基序。删除MLE中的CLAMP结合区域会减少MSL蛋白与雄性X染色体的结合,并增加雄性致死率。这些结果表明,MSL2和MLE中的无结构区域与CLAMP锌指结构域的相互作用对于MSL复合物特异性募集到雄性X染色体很重要。