Visit our Expo - Redox and Inflammation signaling 2012

Session XIV : Transcriptional and translational control Poster XIV, 56
Characterization and functional analysis of human SOX18 promoter
Isidora Petrovic, Milena Stevanovic.
Laboratory for human molecular genetics, Institute of Molecular Genetics and Genetic
Engineering, Vojvode Stepe 444a, 11010 Belgrade, Serbia and Montenegro,
E-mail: hmgbox@eunet.yu
Sox/SOX constitute a large family of genes encoding transcription factors, involved in the
decision of cell fates during development and implicated in the control of diverse
development processes. Human SOX18 gene is expressed in fetal brain as well as in a wide
range of fetal and adult tissues indicating its function is not restricted to early development.
Now it is clear that human SOX18 gene is involved in vascular cell growth and suggest that
this transcription factor may play role in atherosclerosis. The aim of our study has been to
determine and characterize the promoter of the human SOX18 gene and to elucidate
molecular mechanisms underlying the regulation of its expression. We have isolated and
performed the first characterization of human SOX18 promoter. We have identified the
transcription start point and carried out the structural and functional analysis of the regulatory
region responsible for SOX18 expression in HeLa cell line. Using promoter-reporter
constructs, we have determined the minimal SOX18 promoter region that shows basal
promoter activity. Further, we have investigated functional properties of GC-rich motif within
the core promoter sequence. In silico analysis has shown that this motif has several putative
binding sites for transcription factor Sp1 (specificity protein 1). SP1 is characteristic
transcription factor that regulates gene expression within TATA-less promoters, and SOX18
promoter has no TATA box or any other conserved element commonly present in TATA-less
promoter. Our experiments confirmed binding of Sp1 transcription factor to proximal GC-rich
motif. Finally, functional analysis revealed that over expression of Sp1 transcription factor in
HeLa cell line positively regulates the activity of SOX18 promoter.
- 559 -