Simon Fraser University molecular biologist Lynne Quarmby's adventures in pond scum have led her and four student researchers to discover a mutation that can make cilia, the microscopic antennae on our cells, grow too long. When the antennae aren't the right size, the signals captured by them get misinterpreted. The result can be fatal.
In a newly published paper in the science journal Current Biology, the researchers discovered that the regulatory gene CNK2 is present in cilia and controls the length of these hair-like projections.
This discovery is important because cilia, or flagella, dangle from all of our cells. Their ability to propel some cells, such as sperm, and allow molecular communication in others, for example cellular responses to hormones, determines how we develop from embryos and how our bodies function in adulthood.
When cilia are too short or too long they cause various human hereditary diseases and deformities, such as too many fingers or toes, blindness and Polycystic Kidney Disease, which affects one in 600 people.
Quarmby and her doctoral student Laura Hiltonsenior and lead authors, respectively, on this paperare among the few scientists globally who study cilia-disassembly as opposed to -assembly.
A crucial part of all cells' lifecycle is their cilia's disassembly before cell division and assembly after it. The gene LF4 is a known assembly regulator, and, prior to this study, scientists thought that assembly speed controlled cilia's ultimate length or shrinkage. But Quarmby and Hilton have discovered that disassembly speed is also important, and that the regulatory gene CNK2 plays a key role in controlling it.
Similar to how a balance between water pressure and gravity determines the height of a fountain's stream, a balance of assembly and disassembly speed determines cilia's length. When growing and shrinking happen simultaneously cilia length remains constant.
|Contact: Carol Thorbes|
Simon Fraser University