NEW YORK (CNNMoney.com) - Dana Corp. said Friday its U.S. operations have filed for Chapter 11 bankruptcy protection after struggling with declining revenues amid a troubled U.S. auto market.

Shares of Dana (down $0.35 to $0.69, Research) took another hit, falling sharply in midday trading on the news.

Dana shares have plunged in the last year amid troubles in the U.S. auto industry.

Auto industry woes: • GM sees better '06, stock still falls • GM's not so great upgrade • GM and Ford's new cross to bear • A bright, shiny car wreck

The Toledo, Ohio-based auto parts maker filed for protection in bankruptcy court in the Southern District of New York in an effort to address financial and operational challenges, the company said in a statement posted on its Web site.

The move comes just five months after Delphi Corp., the largest U.S. auto parts maker, filed for bankruptcy in October amid growing woes in the U.S. auto industry.

U.S. automakers have steadily been losing market share to their Japanese competitors, a trend that Dana said contributed to its bankruptcy.

General Motors (Research), the world's largest automaker, lost $8.6 billion last year, due to slumping sales, and fellow Detroit rival Ford (Research) also has been experiencing similar problems.

As production levels at U.S. automakers have fallen off, Dana shares have plummeted, falling to less than a dollar from about $14 a year ago.

Rising energy and commodity prices, which outpaced the company's cost savings, also hurt the company's financial condition.

Dana said all facilities would remain open and that normal operations would continue while it restructures. It's secured $1.45 billion in financing for the reorganization.

"The Chapter 11 process provides the company an opportunity to fix our business comprehensively -- financially and operationally. This will be fundamental change, not just incremental improvement," Dana Chairman and CEO Michael J. Burns said in the statement.

-------------

Click here for more breaking news.