Wissenschaftler haben gentechnisch veränderte dürreresistente Pflanzen geschaffen

Forscher versuchen derzeit, die Ursachen für diese bessere Trockenheitsresistenz aufzudecken.

Forscher der Universität Heidelberg entdecken ein entscheidendes Protein in einem Mechanismus, der das Leben von Proteinen reguliert

Proteine ​​dienen in Pflanzen einer Vielzahl von Zwecken und sind nicht nur die Grundbausteine ​​des Lebens. Über 20 Milliarden Proteinmoleküle bilden eine typische Pflanzenzelle, die dazu beiträgt, ihre Struktur zu stabilisieren und den Zellstoffwechsel zu unterstützen.

Forscher des Zentrums für Organismusforschung der Universität Heidelberg haben einen biologischen Prozess aufgeklärt, der die Lebensdauer von Pflanzenproteinen verlängert. Sie haben nun ein entscheidendes Protein namens N-terminale Acetylierung entdeckt, das diesen Mechanismus steuert. Die Ergebnisse der Studie wurden in den Fachzeitschriften Molecular Plant und Science Advances veröffentlicht.

Die N-terminale Acetylierung ist ein chemischer Marker, der sich während der Proteinproduktion entwickelt. Pflanzen tun dies, indem sie eine Essigsäure anbringen[{“ attribute=““>acid residue to the beginning of the protein. The majority of proteins are shielded from degradation by the so-called proteasome, a form of molecular shredder, by this acetic acid residue.

The important protein that has now been found, according to the Heidelberg researchers led by Professor Dr. Rüdiger Hell and Dr. Markus Wirtz, is known as the Huntingtin Yeast Interactor Protein K (HYPK). It promotes N-terminal acetylation, extending the lifespan of plant proteins—important for, among other things, adapting to environmental circumstances.

A graphic comparing phenotype of well-supplied (Control) and drought-stressed wild type (WT) plants and HYPK mutants. The drought stress was applied to approx. five-week-old plants for 24 days. Scale bar = 2 cm. Credit: Miklánková et al., Sci. Adv. 8, eabn6153 (2022), CC BY-NC 4.0

The Heidelberg team used thale cress (Arabidopsis thaliana) to investigate the regulation properties of the HYPK protein. Due to its well-studied genome, the plant from the family Brassicaceae is a popular model organism.

Research on genetically altered plants has shown that the life of proteins is reduced when the HYPK protein is absent and N-terminal acetylation does not take place. At the same time, the plant’s resistance to ongoing drought rises. Rüdiger Hell states, “Our current research is directed to finding out how this improved drought resistance comes about.”

In cooperation with researchers from the Chinese Academy of Sciences in Beijing (China) under the direction of Professor Dr. Yonghong Wang, the Heidelberg scientists also discovered that HYPK performs its regulatory function not only in thale cress but also in rice, one of the world’s oldest crops. The protein is also found in humans and in many fungi.

“The mechanism involved in acetylation and its control by HYPK appears to be one that developed billions of years ago and has been retained in very different organisms to this day,” explains Markus Wirtz.

The studies are being funded by the German Research Foundation.

References: “HYPK promotes the activity of the N^α-acetyltransferase A complex to determine proteostasis of nonAc-X²/N-degron–containing proteins” by Pavlína Miklánková, Eric Linster, Jean-Baptiste Boyer, Jonas Weidenhausen, Johannes Mueller, Laura Armbruster, Karine Lapouge, Carolina De La Torre, Willy Bienvenut, Carsten Sticht, Matthias Mann, Thierry Meinnel, Irmgard Sinning, Carmela Giglione, Rüdiger Hell and Markus Wirtz, 15 June 2022, Science Advances.
DOI: 10.1126/sciadv.abn6153

“OsHYPK-mediated protein N-terminal acetylation coordinates plant development and abiotic stress responses in rice” by Xiaodi Gong, Yaqian Huang, Yan Liang, Yundong Yuan, Yuhao Liu, Tongwen Han, Shujia Li, Hengbin Gao, Bo Lv, Xiahe Huang, Eric Linster, Yingchun Wang, Markus Wirtz and Yonghong Wang, 4 April 2022, Molecular Plant.
DOI: 10.1016/j.molp.2022.03.001