tailieunhanh - Báo cáo Y học: Determination of the consensus binding sequence for the purified embryonic heat shock factor 2

Heat shock transcription factors (HSFs) are characterized by their ability, upon activation, to bind to heat shock response elements (HSE) present in the promoter of their target genes. HSE are composed of inverted repeats of the pentamer nGAAm. In this study, we compare the embryonic HSF2 protein, purified from F9 embryonal carcinoma cells tumor, and thein vitro synthesized HSF2. We show that the context of HSF2 synthesis influences its thermosensitivity and DNA-binding properties. | Eur. J. Biochem. 269 2527-2537 2002 FEBS 2002 doi Determination of the consensus binding sequence for the purified embryonic heat shock factor 2 Martine Manuel1 t. Murielle Rallu1 Marie-Therese Loones1. Vincenzo Zimarino2 Valerie Mezaer1 and Michel Morange1 Laboratoire de Biologie Moléculaire du Stress Unite de Genetique Moléculaire UMR8541 Ecole Normale Superieure Paris France 2DIBIT San Raffaele Scientific Institute Milan Italy Heat shock transcription factors HSFs are characterized by their ability upon activation to bind to heat shock response elements HSE present in the promoter of their target genes. HSE are composed of inverted repeats of the pentamer nGAAm. In this study we compare the embryonic HSF2 protein purified from F9 embryonal carcinoma cells tumor and the in vitro synthesized HSF2. We show that the context of HSF2 synthesis influences its thermosensitivity and DNA-binding properties. Therefore we determined the consensus binding sequence for the purified embryonic HSF2 by the technique of systematic evolution of ligands by exponential enrichment SELEX . We show that embryonic HSF2 prefers sites containing three or four nGAAm inverted pentamers and that its optimal binding sequence contains the 8-mer palindromic core 5 -TTCTAGAA-3 . The consensus binding sequence for the embryonic HSF2 will be very helpful to identify new targets for this factor during developmental and differentiation processes. Keywords heat shock transcription factor-2 protein purification cooperativity SELEX consensus binding sequence. Heat shock factor 2 HSF2 belongs to the vertebrate heat shock factor family that also includes HSF1 HSF3 and HSF4 1-5 . The members of the HSF family are defined by their ability to specifically bind the regulatory sequence heat shock element HSE 6 . Located in the regulatory regions of heat shock genes HSE consists of the inverted repeat of a basal element nGAAm 7 . Two inverted repeats are sufficient for .