shares of calyxt inc surged in premarket trading tuesday after the plantbased synthetic biology company said it would combine with privately held agricultural technology company cibus in an allstock reverse merger calyxt based in roseville minn said its shareholders would own about 5 of the combined company while investors in san diegobased cibus would own about 95 a reverse merger allows a private company to go public by merging with a public one at much less cost than is involved in traditional initial public offerings calyxt said the transaction slated to close in the second quarter would create an agriculturebased geneediting and traitlicensing company led by cibus cofounder rory riggs who will serve as chairman and chief executive calyxt shares closed friday at about 186 cents giving the company a market capitalization just north of 9 million the shares were recently up nearly 80 to 334 cents in premarket trading tuesday