P-element Somatic Inhibitor Protein Binding a Target Sequence in dsx Pre-mRNA Conserved in Bombyx mori and Spodoptera litura

• Published in: International journal of molecular sciences Vol. 20; no. 9; p. 2361
• Main Authors: Wang, Yao, Zhao, Qin, Wan, Qiu-Xing, Wang, Kai-Xuan, Zha, Xing-Fu
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 13.05.2019; MDPI
• Subjects: Alternative splicing; Alternative Splicing - genetics; Amino acid sequence; Amino acids; Animals; Binding; BmPSI; Bombyx - genetics; Bombyx mori; Calorimetry, Differential Scanning; Circular Dichroism; circular dichroism (CD) spectroscopy; Competition; Conserved sequence; Electrophoretic Mobility Shift Assay; electrophoretic mobility shift assay (EMSA); Exons - genetics; Experiments; Female; Insect Proteins - genetics; Insects; isothermal titration calorimetry (ITC); KH_1 motif; Male; mRNA; Mutation; P elements; Protein Binding; Proteins; RNA Splicing - genetics; Sex determination; Splicing; Spodoptera - genetics; Spodoptera litura; Spodoptera litura; circular dichroism (CD) spectroscopy; electrophoretic mobility shift assay (EMSA); Bombyx mori; KH_1 motif; isothermal titration calorimetry (ITC); sex determination; BmPSI
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms20092361

( ) functions as a double-switch gene in the final step of the sex-determination cascade in the silkworm . The P-element somatic inhibitor (PSI) protein in interacts with pre-mRNA in CE1 as an exonic splicing silencer to promote male-specific splicing of . However, the character of the interaction between BmPSI and pre-mRNA remains unclear. Electrophoretic mobility shift assay (EMSA) results showed that the four KH_1 motifs in BmPSI are all essential for the binding, especially the former two KH_1 motifs. Three active sites (I116, L127, and IGGI) in the KH_1 motif were found to be necessary for the binding through EMSA, circular dichroism (CD) spectroscopy, and isothermal titration calorimetry (ITC). The PSI homologous protein in (SlPSI) was purified and the binding of SlPSI and CE1 was verified. Compared with BmPSI, the mutant SlPSI proteins of I116 and IGGI lost their ability to bind to CE1. In conclusion, the binding of PSI and pre-mRNA are generally conserved in both and . These findings provide clues for sex determination in Lepidoptera.