Moosgene give insight into herbal landings
Deciphering the first moss closes vital gapsRead out
An international consortium has decoded the genome of a moss. This is significant because it makes it possible for the first time to study the genetic changes that have made possible the conquest of the mainland by the plants. This milestone in biology has now been published in the journal Science.
So far, only a few plants have made it to the list of sequenced organisms. So far, especially flowering plants such as the model plants thale cress and the poplar or crops such as rice were of interest. But also algae are represented. These are at the very beginning of the development of plants, flowering plants at the very end. However, one representative was missing for the developmentally crucial step of the transfer of the plants from the water to the land and the development of the Mehrzelligkeit approximately 450 million years ago.
This gap has now been closed by an international research team of 70 scientists led by the Moosgenom Consortium and the Joint Genome Institute (JGI) in Walnut Creek, California. The researchers analyzed the genome of the "small bubble cap moss" and can now by comparing the genome of different plants get completely new insights into the genesis of complex processes of cell regulation and communication between cells.
Mosses are much more complex than algae, but not as sophisticated as flowering plants, which have a sophisticated vascular system and complexly shaped reproductive organs. The transition from water to land was a big step for the plants, which involved the adaptation of many cellular processes. These changes are well documented in the genetic material - that is, in the now decoded genome sequence - making it a unique resource for future research.
The invention of hormones
Already, the moss revealed some secrets, for example how the tolerance against dehydration or how the mode of action of plant hormones developed. Anyone who has ever dried up a houseplant has virtually proved that drought tolerance, although an important feature, is no longer present in most flowering plants. Because the sequence of the small bladder moss (Physcomitrella patens) shows that the original land plants were probably still tolerant to dehydration and that this property was lost in our modern plants. display
In plants, too, hormones control crucial steps in development and growth. However, while plant hormones in algae do not seem to exist, they were already invented in the ancestor of our present-day land plants, as evidenced by the genome of the small bubble moss. From the comparison with the genome of today's plants, the researchers can draw important conclusions about how plant hormones have developed.
DNA repair investigated
Two German research institutions were also involved in the publication in Science, the University of Freiburg im Breisgau and the K lner Max Planck Institute for Research on Zoology. The researchers at the K lner Max Planck Institute were particularly interested in the repair of DNA damage in Physcomitrella. This process is important for warding off damaging environmental influences and in humans also in the development of cancer and aging.
"DNA damage in Physcomitrella is being repaired with precision, which undoubtedly contributes to the high stability of the Physcomitrella genome, " explains Bernd Reiss, group leader at the Max Planck Institute in K ln the research results. "From human medical research, we know that errors in the genome can lead to disease. Therefore, it is of great interest to understand the mechanisms that lead to this genome stability. "
(MPG, 14.12.2007 - NPO)