Genes from tiny marine algae opens new avenues of research

Washington, April 11 (ANI): By sequencing the DNA of two tiny marine algae, a team of scientists has opened up a myriad of possibilities for new research in algal physiology, plant biology, and marine ecology.

The project was led by Alexandra Worden at the Monterey Bay Aquarium Research Institute (MBARI) and the Joint Genome Institute (JGI).

The genome analyses involved a collaborative effort between MBARI, JGI, and an international consortium of scientists from multiple institutions, including University of Washington, Ghent University (Belgium), and Washington University in St. Louis.

Biologists generally agree that all land plants, from tiny mosses to giant redwoods, evolved from an ancestral green alga.

Some of the closest representatives of these ancestral green algae living today are thought to be the Prasinophytes, a group of microscopic green algae found across the world's oceans.

Microbial oceanographer Alexandra Worden led a team of scientists that sequenced the genomes of two Prasinophytes in the genus Micromonas. Each Micromonas cell is only about one fiftieth the width of a human hair.

However, they are widespread and may serve as important links in marine food webs. They may also influence the amount of carbon dioxide the oceans take up from the atmosphere.

Worden's team spent four years compiling a complete list of the approximately 21 million chemical building blocks (called bases) that make up Micromonas' DNA.

Worden and her fellow researchers discovered that Micromonas carries a significant number of genes that are not found in the genomes of other green algae.

Some of these genes, however, are found in land plants or bacteria. Worden's team is currently trying to find out the functions of these genes in Micromonas.

Such information will help researchers better understand how Micromonas interacts with its environment and with other marine organisms.

According to Worden, "One of our main findings is that some genes that were thought to be land-plant specific were also found in Micromonas."

"It's possible that land plants could have developed these genes and Micromonas also developed them. Or perhaps an organism (the ancestral alga) that preceded both land plants and Micromonas had them, which is the simpler explanation," she said.

In addition to highlighting a number of genes whose functions are known from other organisms, Worden's team found that a large number of the genes in Micromonas have no known function.

"We know they're real. They're expressed and we've seen them in other organisms, but they're not genes that anyone has characterized, so no one knows what they do," said Worden. (ANI)