Chlamydomonas performs photosynthesis like plants, by converting carbon dioxide, water and the energy of sunlight into oxygen and sugars. Indeed, much of what is known about photosynthesis was learned from Chlamydomonas.
"Now we have learned that we don't know everything about photosynthesis and that there are still many unknown proteins," Merchant said. "We found many proteins involved in antioxidant function. Photosynthesis generates the most powerful oxidants known in biology; there has to be a protection mechanism because oxidation causes aging. In Chlamydomonas, proteins and lipids can get oxidized if reactions of photosynthesis are not properly controlled. We discovered a number of proteins that may be important for protection against oxidative damage."
The scientists identified 349 genes that are present in algae and plants but not in humans and other animals. More than 200 of these genes have unknown functions, a fact that surprises the researchers.
"It's exciting that most of these genes are unknown," Merchant said, adding that the scientists suspect that many of these genes are involved in photosynthesis.
"We don't know what they do yet; we hope to learn what they do," she said.
The scientists identified many new proteins that are likely associated with cilia thin organelles that allow a cell to sense its environment and tell where it is and they differentiated proteins that are critical for movement from those associated with sensory functions. The cilia provide locomotion and act as a cellular antenna.
Humans also have cilia in the brain, lungs and kidneys. The cilia are required for brain function in animals, and for metabolism. The loss of cilia leads to serious diseases, although scientists do not yet know why, Merchant said. Cilia perform key functions for a large number of organs, and the conseque
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University of California - Los Angeles