Skip to main content
. 2021 Jul 7;12:4170. doi: 10.1038/s41467-021-24407-y

Fig. 2. M1BP promotes gypsy-dependent enhancer-blocking and barrier activities.

Fig. 2

a Western blotting of male third instar larval extracts for M1BP, insulator proteins, and Pep loading control in control and M1BPRNAi knockdown flies using Act5C-Gal4 driver. Samples from the same experiment were run on different lanes of the same gel for proteins with similar molecular weights. Western blotting experiments were performed using two independent biological replicates with similar results. b M1BP promotes enhancer-blocking activity at ct6. Top: schematic diagram of reporter system. The gypsy retrotransposon is inserted in between the promoter of cut and wing margin (EnWing) enhancer. Bottom: insulator activity for ct6 was scored in male flies on a scale of 0–4. 0, no notching; 1, slight notching in anterior tip of wing; 2, mild notching throughout posterior wing; 3, extensive notching both in anterior and posterior wing; 4, severe notching throughout the anterior and posterior wing. c Graph represents quantification of ct6 wing phenotype of male wild-type (+/+) and M1BPRNAi using Ser-Gal4 driver. n, total number of flies scored. d Depletion of M1BP shows reduced gypsy-dependent barrier activity in all tissues tested. Schematic diagram of non-insulated UAS-luciferase system shows spreading of repressive chromatin can reduce luciferase expression, but presence of the gypsy insulator acts as a barrier and allows for luciferase activity. e Relative luciferase activity of insulated or non-insulated male larvae of control and M1BPRNAi driven by Act5C-Gal4 driver, f Mef2-Gal4 driver, and g l(3)31-1-Gal4 driver. Luciferase values of all genotypes are plotted as box and whisker plots using one-way ANOVA followed by Tukey HSD post hoc tests to calculate P values for pairwise comparisons. The box represents the 25–75th percentiles, and the median is indicated. The whiskers show the minimum and maximum values. For each genotype, n = 12 individual larvae. Bracket indicates P values of two-way comparisons (*P < 0.05) and all comparisons are shown in Supplementary Table 4.