Abstract

Since Oct-1 is a ubiquitous DNA binding protein shown to play an important role in regulating cell proliferation and possess structural characteristics consistent with a nitric oxide (NO) target, we studied NO regulation of the DNA binding activity of Oct-1 in the A7R5 vascular smooth muscle cell (VSMC) line. Two NO donors, sodium nitroprusside (SNP) and S-nitrosoacetyl-penicillamine (SNAP) were directly added to the nuclear extract-oligonucleotide reaction mixture, respectively and the effect on Oct-1 DNA binding activity was evaluated by gel shift assay. Both NO donors (0.01–1 mM) inhibited the DNA binding activity of Oct-1. This inhibitory effect was not attenuated by dithiothreitol (DTT) (1 mM) while in contrast, DTT did antagonize the effect of diamide on Oct-1 DNA binding activity. The NO effect on Oct-1 has some specificity; as the NO donors had no effect on myc DNA binding activity. The inhibitory effect of NO donors was reproduced in A7R5 cells, without affecting their viability. These findings provide the first evidence that NO inhibits the DNA binding activity of Oct-1, probably through a cGMP independent mechanism and suggests that NO may inhibit mitogenesis in part through an effect on Oct-1 DNA binding activity in VSMCs.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.