Big discovery over molecule

Press, 24 November 1982, Page 41

Big discovery over molecule

NZPA Boston A discovery that one of the most important molecules of life, RNA, can split and rearrange itself without the help of proteins has been announced by a team of scientists in Colorado.

The findings support an older idea that single-strand RNA, rather than doublestrand DNA, may have been the important carrier of genetic information as life began on this planet. This highly unusual type of RNA (ribonucleic acid) was found inside a creature called Tetrahymena, a single-cell organism found in pond water. This discovery was described by a scientific journal, “Cell,” as an unprecedented event. The finding was reported by Dr Thomas Cech, from the University of Colorado. “It is a fantastic discovery,” said Professor Joan

Steitz, a member of the department of biophysics and biochemistry at Yale University. “It opens a whole new dimension to our understanding of what RNA molecules can do in cells.

“The discovery is so novel that one does not know the full implications, but it will certainly change the way we discuss things,” said Phillip Sharp, a biologist at /the Massachusetts Institute of Technology. According to “Cell” the newly discovered RNA molecule is able to rearrange its internal structure by cleaving itself at specific locations and then joining certain fragments in a specific new sequence. In other words, this newly discovered RNA can rearrange itself, thus altering the information it carries.

This means that RNA — usually thought of as a rela-

tively stable messenger molecule within the cell — can also perform a function normally reserved for enzymes. The findings provide a new way by which genetic information can be changed, which suggests that it could have been important in evolutionary developments, since it would allow changes in genetic information in less complicated steps. Scientists consider the DNA molecule the basic carrier of genetic information, encoding all of the instructions for the building and functioning of living creatures. Professor Steitz said that Dr Cech’s discovery may have meaning for “all sorts of things, starting with evolution, to the functioning of the mammalian cell. This casts a whole new perspective on how we should think of the RNA molecule.”