COMPARISON OF SEQUENCES OF A TRANSCRIPTIONAL COACTIVATOR MBF2 FROM 3 LEPIDOPTERAN SPECIES BOMBYX-MORI, BOMBYX-MANDARINA AND SAMIA-CYNTHIA

MBF2 was first isolated from the silkworm Bombyx mori as a positive co factor that activates transcription through its interaction with TFIIA . To identify conserved domain(s) within the MBF2 molecule, we isolate d cDNAs encoding MBF2 homologues from other silkworms Bombyx mandarina and Samia cynthia. Bacterially expressed and purified MBF2 of B. mand arina and S. cynthia activated transcription in vitro. The predicted a mino acid sequences of MBF2 from two Bombyx species share 97% homology . When we compared between B, mori and S. cynthia factors, the homolog y reduced to 50%. Four regions in MBF2 are conserved among these three species. Two of them are present in the middle region of MBF2 that is essential for the transcriptional activation. (C) 1998 Elsevier Scien ce B.V. All rights reserved.