MOSCOW, March 3. /TASS/ An international research team from Russia, Germany, and the USA have collected and analyzed data on how the plant hormone auxin influences the development of plants, the Computational Transcriptomic and Evolutionary Bioinformatics Laboratory at Novosibirsk State University (NSU) reported. In their study, the biologists used data both from experiments and from mathematical modeling. Such research, which enhances the understanding plants’ biochemistry will fine-tune the development of plants to the needs of people.
"In our work, we have revised an intricate regulatory action network of one of the most important plant hormones, auxin; the formula which describes how on a molecular level, auxin controls the activity of genes crucial for the development of seeds, separate parts of a plant (roots and stems) and of a plant as a whole," said Victoria Mironova, the first author of the review published recently in the journal Trends in Plant Science, and Head of Computational Transcriptomic and Evolutionary Bioinformatics Laboratory at NSU, Head of Sector for Systems biology of plant morphogenesis at the Institute of Cytology and Genetics of RAS.
System’s complexity
There are many participants and various biochemical reactions involved in auxin’s function. The appearance of the hormone in cells simultaneously induces the synthesis of some proteins and activates inhibitors which, in turn, slow down the synthesis of the same proteins. So, this explains the fact that to address the role of auxin, various mathematical models need to be applied.
"In the network studied, we deal with a great variety of participants, an array of transcription factors - proteins ensuring an activation of genes, their inhibitors, various modulators and, of course, the auxin itself," Mironova explained. "Consequently, it is next to impossible to study auxin using traditional genetics techniques by switching-off genes. So in this case, we break the activity of a certain gene, yet almost nothing happens since there exists a number of duplicate ways, which hinder phenotypic abnormalities due to a breakdown in one gene."
Mathematical modeling
The only way to master this systematic analysis of such a diverse set of factors and to unlock the secrets of plant development, is by using the mathematical modeling approach. For instance, in one scientific work mentioned in the review, the oscillations of activities by auxin-sensitive genes in some tissues were first predicted theoretically, followed by experimental studies on the root zone, where every six hours the activity of genes responsible for the formation of side roots either grows or drops down.
Therefore, the mathematical modeling can provide insights into the transition zone between molecular and cellular organization levels of plants which is practically inaccessible using experiments. The review’s authors believe that soon a number of similar, or even more intricate models will appear to fill the gaps in knowledge on all three levels of structures of all living beings and clarify the transition processes between molecular and cellular levels, between cellular and tissue ones, as well as between tissue and organism ones.
Eventually, such mathematical tools can be used to fine-tune plant growth, for example, growing their roots and sprouts in unfavorable conditions or yielding plants at a suitable speed and influencing their nutritional composition.