Journal: PLoS ONE
Article Title: The Human Proteins MBD5 and MBD6 Associate with Heterochromatin but They Do Not Bind Methylated DNA
doi: 10.1371/journal.pone.0011982
Figure Lengend Snippet: A- The MeCP2, MBD5 and MBD6 MBDs, tagged with 6×His, were expressed in bacteria, purified, and examined on a Coomassie-stained SDS-PAGE gel. Apparent weights of migration markers, in kDa, are indicated. B-Gel retardation assay with probe SL1 and the proteins of panel A. In this panel and the following, the probe is depicted as a line; open circles represent an unmethylated CpG, and filled circles a methylated CpG. In panels 2B–2D, the dash indicates the probe-only lane (no protein added). “MeCP2” : MBD domain of MeCP2, tagged with 6×His; same abbreviation for MBD5 and MBD6. C-Gel retardation assay with probe SL2 and the proteins of panel A. D-Gel retardation assay with probe SL3 and the proteins of panel A. E- The MeCP2, MBD5 and MBD6 MBDs, tagged with Maltose-Binding Protein (MBP), were expressed in bacteria, purified, and examined on a Coomassie-stained SDS-PAGE gel. F-Gel retardation assay with probe SL3, and the proteins of panel E. “MeCP2” : MBD domain of MeCP2 tagged with MBP; same abbreviation for MBD5 and MBD6. “MBP” : Maltose-Binding Protein only lane. G- The MBDs of MBD5 and MBD6, tagged with GST, were expressed in bacteria, purified, and examined on a Coomassie-stained SDS-PAGE gel. A region of MBD5 larger than just the MBD was included in this experiment, explaining the higher molecular weight. H-Gel retardation assay with probe SL4. “ZBTB4”: Zinc fingers of ZBTB4 fused to GST; “MBD5” : MBD domain of MBD5 fused to GST, same abbreviation for MBD6. “GST”: GST-only lane. I-Gel retardation assay with probe SL5 and the proteins used in panel H. Probe SL5 contains 6 randomized positions (“N”), on either side of the CpG. Legend as in panel H.
Article Snippet: We additionally cloned the MBD of MBD6 and MBD6 into an MBP fusion plasmid (pMALp2X, New England Biolabs) and a GST fusion fusion plasmid (pGEX-5X-1, GE Heathcare).
Techniques: Purification, Staining, SDS Page, Migration, Electrophoretic Mobility Shift Assay, Methylation, Binding Assay, Molecular Weight, Zinc-Fingers