Expression, purification, and structural prediction of the Ets transcription factor ERM.

Autor: Mauen S; Laboratoire de Virologie Moléculaire-Faculté de Médecine, ULB, CP 614, 808 route de Lennik, 1070 Brussels, Belgium., Huvent I, Raussens V, Demonte D, Baert JL, Tricot C, Ruysschaert JM, Van Lint C, Moguilevsky N, de Launoit Y
Jazyk: angličtina
Zdroj: Biochimica et biophysica acta [Biochim Biophys Acta] 2006 Aug; Vol. 1760 (8), pp. 1192-201. Date of Electronic Publication: 2006 Mar 31.
DOI: 10.1016/j.bbagen.2006.03.007
Abstrakt: The PEA3 group within the Ets family comprises PEA3, ER81, and ERM, three transcription factors of about 500 residues. These factors are highly conserved in their ETS DNA-binding domain and in their two transcriptional activation domains. They are involved in many developmental processes and regulate cancer development via metastasis, as in the case of some breast tumors. Here, we describe the oversynthesis of human ERM from a baculovirus expression vector in Spodoptera frugiperda (Sf9) cells, and the subsequent purification and structural characterization of this protein. Oversynthesis of ERM was confirmed by measuring band intensities on SDS-PAGE gels and by Western blot analysis. Two-step purification by affinity chromatography led to a highly stable protein. Electromobility shift assays suggested that this purified protein is functional, since it recognizes specific Ets DNA-binding sites. We then used circular dichroism and infrared spectrometry to perform a structural analysis of the purified full-length ERM, and compared the results with those of current structural prediction algorithms. Our study indicates that ERM contains a highly structured ETS-domain and suggests that each of the N- and C-terminal transactivating domains also contains an alpha-helix. In contrast, the 250-residue central domain seems to have very little structure.
Databáze: MEDLINE