LOS ANGELES (AP) — "CSI" star Marg Helgenberger has filed for divorce from her husband, fellow actor and Screen Actors Guild President Alan Rosenberg.

She filed her petition Tuesday in Los Angeles, citing irreconcilable differences.

The couple got married in 1989 and have a son together.

The 50-year-old Helgenberger plays Catherine Willows on CBS' highly rated drama, "CSI: Crime Scene Investigation." She won a best supporting actress Emmy in 1990 for the series "China Beach."

The 58-year-old Rosenberg was a regular on the TV series "LA Law" and "The Guardian," and received an Emmy nomination for a guest role on "ER." He is the current president of SAG, which remains embroiled in contract negotiations with Hollywood producers over a new contract for actors.

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