Down-Regulation of Human MAZ Gene Promoter Activity by Transcription Factor Elk-1 In Vitro

Abstract: The aim of this work is to investigate the transcriptional regulation of the myc-associated zinc finger protein (MAZ)， also known as serum amyliod A activating transcription factor (SAF)， which plays a key role in regulation of variety of inflammation-responsive genes as well as transcription of multiple genes modulating tumor microenvironment. The down-regulation of MAZ promoter activity by Sp1 and MAZ were identified. In this study， the transcription factor ETS-like 1 transcription factor (Elk-1) binding site for regulating MAZ transcription was identified by PROMO software online and electrophoretic mobility shift assay (EMSA). The expressions of both SAF-1 and SAF-3， the two transcription variants of MAZ gene， were analyzed by MAZ promoter driving bichromatic fluorescent reporter system when Elk-1 was over-expressed. The results showed that the region between –525 and –504 bp in MAZ promoter region could be bound with Elk-1. The expressions of both SAF-1 and SAF-3 were inhibited when Elk-1 was over-expressed. In comparison to transcription factor Sp1， it seems that Elk-1 is moderate inhibitor for MAZ promoter activation. Based on our observations， it is suggested that as a down-regulation transcription factor for MAZ promoter activation， Elk-1 may play roles in physiological and pathological procedures in human cells， such as inflammation reaction and tumorigenesis. The hypothesis needs to be confirmed by further analysis in vivo.

CSTR: 32200.14.cjcb.2017.06.0004