Researchers at the Agency for Science, Technology and Research's (A*STAR) Institute of Molecular and Cell Biology (IMCB) have discovered new molecular mechanisms that provide a more detailed understanding of how the normally benign Dr. Jekyll-like fungus known as Candida albicans transforms into a serious and often life-threatening Mr. Hyde-like form.
C. albicans can cause serious and potentially life-threatening infections in the mouth, blood and other tissues of people who are undergoing cancer chemotherapy or radiation treatments, or who have developed AIDS or other diseases that damage the immunity of the individual.
In two separate papers published last month in Developmental Cell and in August in the EMBO journal, the team of scientists led by Wang Yue, principal investigator at IMCB, have managed to reveal previously unknown mechanisms which are responsible for causing the infectious phase of C. albicans.
The fungus starts its 'attack' on a patient by changing its oval shape into a filamentous form, which has thin, threadlike appendages emerging from the cell body. Wang's team, who has been studying C. albicans for more than seven years, was responsible for identifying the master "controller" protein called Hgc1 in 20041.
This "controller" functions like a regulator and tells the fungus when to start the transformation from the harmless oval shape to the infectious filamentous form.
"One question remained, however - how does it activate the cellular machineries that determine the fungal cell shape?" said Wang.
Wang's team found the answer to this question in two proteins called Rga2 and Cdc11. They discovered that they each function like a switch on two different cellular machineries that normally determines cell shape. "The master regulator Hgc1 acts like the 'finger' that flips the switches to start the infection process," said Wang.