NEW YORK ( TheStreet) -- Stocks trading for less than $5 can experience large percentage moves on heavy volume for any number of reasons. TheStreet's Dollar Store examines some of this week's biggest under-$5 stock movers and the catalysts for the trading action.Sirius XM ( SIRI) shares rose nearly 9% during a busy week for the satellite radio company. On Tuesday, Janco Partners analyst Martin Pyykkonen upgraded Sirius XM to buy from accumulate and raised his stock price target to $1.30 from 80 cents, citing the company's operating leverage on a market rebound. Sirius XM shares didn't react much to the upgrade, though, and traded in a very narrow range. The stock opened Tuesday at 97 cents, went as high as 99 cents and closed at 96 cents. Volume, however, was a different story. More than 205 million shares of Sirius XM changed hands during the session, making it one of the most active stocks on the exchanges. The following day, Sirius XM said it added 171,441 net subscribers in the first quarter of 2010, ending the three-month period with 18.94 million subscribers. Sirius XM said deactivations fell by 11% compared with the first quarter of 2009, while gross additions rose 29%. > > Bull or Bear? Vote in Our Poll Once again, the stock traded on massive volume, this time topping 216 million shares. And for the first time in more than a month, Sirius XM shares closed above the $1 mark. April, as it turns out, has been an incredibly busy month for Sirius XM traders. The 50-day average daily share volume for Sirius XM currently is 166.66 million as of Friday. Only three times this month has daily share volume on Sirius XM fallen below that average. More than 251 million shares would change hands on Thursday, when the stock closed at $1.11. Things may come to a head on April 29, when Sirius XM will meet with a Nasdaq listing committee for a hearing on the stock's continued listing on the exchange. Sirius XM has been unable to satisfy the Nasdaq's minimum bid price requirement since the company was initially issued a warning in September 2009. Janco Partners' Pyykkonen isn't concerned about a Sirius XM delisting, though. "Sirius XM's stock is clearly right on the borderline in attempting to sustain a $1 or higher price for Nasdaq's minimum requirements," Pyykkonen wrote in his research note Tuesday. "The most likely scenario is for Nasdaq to grant a six month extension on a delisting decision."