Figure 6

Mblk-1 upregulates its own expression via GAGA motif-containing regions. (A) Two ChIP-seq peak signals were identified upstream of the Mblk-1 gene (outlined in black). Construction of the pGL4.23 reporter vector used in the luciferase assay is indicated below the Mblk-1 gene structure. The transcription start site of the Mblk-1 gene is indicated by a blue arrow. (B) Results of the luciferase assay using a reporter vector containing the Mblk-1-binding region sequence and a control vector. Data represent means ± SD (n = 4). Significant difference is indicated by 3 asterisks (p < 0.005, Student’s t test). (C) Phylogenetic tree showing the relationship among hymenopteran species and Drosophila melanogaster. (D) Comparison of the relative expression of the Athalia rosae Mblk-1 homolog with respect to RpL32 among various adult body parts (head without brain, brain, thorax, and abdomen, n = 3). Black circles represent values from 3 experiments and yellow circles represent their average values. Because expression of the Mblk-1 homolog in brain samples was below the detection threshold, brain Cp values were set to 40 in a total of 45 PCR cycles and the relative expression levels were calculated. (E) Relationship between the number of GAGA and GAG sequences localized within 2 kb upstream of Mblk-1 homologs and expression of Mblk-1 homologs in adult MBs of various hymenopteran insect species. Yellow and gray bars indicate the number of GAGA and GAG sequences, respectively. Table below shows whether Mblk-1 homolog is expressed in the adult MBs in each species.