Interaction between the inner nuclear membrane lamin B receptor and the heterochromatic methyl binding protein, MeCP2

Lamin B Receptor Recognizes Specific Modifications of Histone H4 in Heterochromatin Formation

“…Arrows and asterisks indicate GAL4-LBR fragments and nonspecific bands, respectively. transcriptional repression (41,42). Thus, we speculate that primitive heterochromatin provides a structural framework to recruit transcriptional repressors to form mature heterochromatin (Fig.…”

Basic concepts of epigenetics

“…Lamins directly interact with H3K9me3 and MeCP2/ Sin3A, which bind to lamin B, HP1γ and HP1α. 55,157 Lamins also adhere to lamin-associated polypeptides and, at the inner membrane, bind with emerin, Sun1 and Sun2, which anchor nesprin-3 on the outer side, where it binds to cytoskeletal actin via a Klarsicht/ANC-1/Syne homology domain. Moreover, on the outside membrane, nesprin-2 forms complexes with kinesin-1 motor protein apparatus by associating with and recruiting KLC1 to the outer nuclear membrane, which requires lamin A and C. Ultimately, the kinesin-1/nesprin-2/SUN complex spans the entire nuclear envelope in order to anchor cytoskeletal structures to nuclear lamina.…”

“…MeCP2 is a prominent silencing mark that is heavily embedded in heterochromatin located throughout the lamina circumscribing the nuclear envelope. 55 Similar to MBD1, MeCP2 also contains a TRD unit that, in this case, binds to the pre-initiation transcription machinery (TFIIB) that prevents transcription by RNAP II and docks to the paired amphipathic helix protein Sin3A. 56,57 Yeast Sin3 (Sin3A and Sin3B) serve as co-repressors that bring histone deacetylase activity in very close proximity to genes targeted for silencing.…”

Lamin B receptor

“…49 The authors view this observation as demonstrating that LBR plays a role in the orchestrated transition from histones to protamines, which may also involve the RS protein kinase 32 and p32. 30 A provocative recent study 50 presents evidence that a methylated DNA binding protein (MeCP2) binds directly to LBR, thus bringing certain heterochromatic regions into proximity to the NE. Most interphase MeCP2 is distributed throughout the nucleus, with a small fraction co-localized with LBR.…”