Promoter (noun)

1. A person or organization that works to promote or publicize a product, service, or event.
2. A person who is instrumental in the formation and development of a business or organization.
3. A genetic element that increases the expression of a gene or genes.

Origin:

From old french promoteur, from latin promotor ("a setter forward, a patron, a defender"), from promovere ("to set forward, to promote"), from pro- ("forward") + movere ("to move").

Examples:

1. The promoter of the concert worked hard to make it a success.
2. The promoter of the new restaurant helped create a buzz around the opening.
3. As a promoter, he was able to bring in big names to the venue.
4. He was the promoter of the company's new product line.
5. The promoter region of a gene is the site where regulatory proteins bind to control its expression.