Chloroplast Development & Thylakoid Biogenesis
Our research delves into the critical process of thylakoid membrane development and maintenance within chloroplasts. Thylakoid membranes, essential for photosynthesis, drive plant life by harnessing light energy. However, the mechanisms of their biogenesis, in particular bilayer deposition remains largely unknown. Vesicle transport, membrane contact sites between the thylakoid and inner envelope membranes and the action of lipid transport proteins are conceivable mechanisms proposed for membrane development.
Using Arabidopsis as a model organism, we aim to decipher the complex process of bilayer deposition and membrane shaping. By utilizing mutants of known and unknown factors we are exploring how defects in this process impact plant viability. Additionally, we are focusing on the dynamic responses of the chloroplast and thylakoids under both normal and stress conditions, such as heat and drought. Our interdisciplinary approach integrates cell biology, molecular biology and biophysics to study membrane assembly.
Etage/Raum: 01.69
Research Technologies
Biomimetic Systems:
Chloroplasts have a unique lipid composition with more than 75% galacto- and only few sulfo- and phospholipids. We utilize giant unilamellar vesicles (GUVs) as in vitro systems to replicate the native membrane environment of thylakoids to simulate and study membrane fusion, lipid bilayer formation, and protein-membrane interactions. This approach allows us to investigate membrane dynamics and the role of specific lipids and proteins in thylakoid biogenesis under controlled conditions.
Live Cell Imaging of Membrane, Protein and Lipid Dynamics in plastids:
By utilizing multicolor fluorescence microscopy, we track dynamic changes in chloroplast architecture under normal growth conditions and stress responses. Our research employs cutting-edge genetic biosensors to observe real-time dynamics of lipids, proteins, and other molecular markers in living Arabidopsis and tobacco cells within chloroplasts in response to various stimuli.
Electron Microscopy:
High-resolution transmission electron microscopy (TEM) allows us to examine the ultrastructure of chloroplasts with unparalleled detail. Through this technique, we identify new structural features and abnormalities in thylakoid membranes, helping us uncover the molecular underpinnings of thylakoid biogenesis. TEM also enables the visualization of changes in membrane organization under stress conditions, revealing how chloroplasts adapt to environmental challenges.
Publikationen
Sedaghatmehr M, Pramanik S, Dimova R, Erban A, Kopka J, Hertle AP. Insights into CPSFL1 Induced Membrane Dynamics: A Multifaceted Regulator Linking Vesicle Formation to Thylakoid Biogenesis. BioRxiv. 2025.
Sedaghatmehr M, Rößler S, Hertle AP. New evidence for the presence and function of phosphoinositides (PPIs) in the chloroplast BioRxiv, 2024.
1: Krämer C, Boehm CR, Liu J, Ting MKY, Hertle AP, Forner J, Ruf S, Schöttler MA, Zoschke R, Bock R. Removal of the large inverted repeat from the plastid genome reveals gene dosage effects and leads to increased genome copy number. Nat Plants. 2024 Jun;10(6):923-935. doi: 10.1038/s41477-024-01709-9. Epub 2024 May 27. PMID: 38802561; PMCID: PMC11208156.
2: Uflewski M, Rindfleisch T, Korkmaz K, Tietz E, Mielke S, Correa Galvis V, Dünschede B, Luzarowski M, Skirycz A, Schwarzländer M, Strand DD, Hertle AP, Schünemann D, Walther D, Thalhammer A, Wolff M, Armbruster U. The thylakoid proton antiporter KEA3 regulates photosynthesis in response to the chloroplast energy status. Nat Commun. 2024 Mar 30;15(1):2792. doi: 10.1038/s41467-024-47151-5. PMID: 38555362; PMCID: PMC10981695.
3: Sandoval-Ibáñez O, Rolo D, Ghandour R, Hertle AP, Armarego-Marriott T, Sampathkumar A, Zoschke R, Bock R. De-etiolation-induced protein 1 (DEIP1) mediates assembly of the cytochrome b6f complex in Arabidopsis. Nat Commun. 2022 Jul 13;13(1):4045. doi: 10.1038/s41467-022-31758-7. PMID: 35831297; PMCID: PMC9279372.
4: Agrawal S, Karcher D, Ruf S, Erban A, Hertle AP, Kopka J, Bock R. Riboswitch-mediated inducible expression of an astaxanthin biosynthetic operon in plastids. Plant Physiol. 2022 Jan 20;188(1):637-652. doi: 10.1093/plphys/kiab428. PMID: 34623449; PMCID: PMC8774745.
5: Hertle AP, Haberl B, Bock R. Horizontal genome transfer by cell-to-cell travel of whole organelles. Sci Adv. 2021 Jan 1;7(1):eabd8215. doi: 10.1126/sciadv.abd8215. PMID: 33523859; PMCID: PMC7775762.
6: Hertle AP, García-Cerdán JG, Armbruster U, Shih R, Lee JJ, Wong W, Niyogi KK. A Sec14 domain protein is required for photoautotrophic growth and chloroplast vesicle formation in Arabidopsis thaliana. Proc Natl Acad Sci U S A. 2020 Apr 21;117(16):9101-9111. doi: 10.1073/pnas.1916946117. Epub 2020 Apr 3. PMID: 32245810; PMCID: PMC7183190.
7: Armarego-Marriott T, Kowalewska Ł, Burgos A, Fischer A, Thiele W, Erban A, Strand D, Kahlau S, Hertle A, Kopka J, Walther D, Reich Z, Schöttler MA, Bock R. Highly Resolved Systems Biology to Dissect the Etioplast-to-Chloroplast Transition in Tobacco Leaves. Plant Physiol. 2019 May;180(1):654-681. doi: 10.1104/pp.18.01432. Epub 2019 Mar 12. PMID: 30862726; PMCID: PMC6501100.
8: Maclean AE, Hertle AP, Ligas J, Bock R, Balk J, Meyer EH. Absence of Complex I Is Associated with Diminished Respiratory Chain Function in European Mistletoe. Curr Biol. 2018 May 21;28(10):1614-1619.e3. doi: 10.1016/j.cub.2018.03.036. Epub 2018 May 3. PMID: 29731304.
9: Armbruster U, Rühle T, Kreller R, Strotbek C, Zühlke J, Tadini L, Blunder T, Hertle AP, Qi Y, Rengstl B, Nickelsen J, Frank W, Leister D. The photosynthesis affected mutant68-like protein evolved from a PSII assembly factor to mediate assembly of the chloroplast NAD(P)H dehydrogenase complex in Arabidopsis. Plant Cell. 2013 Oct;25(10):3926-43. doi: 10.1105/tpc.113.114785. Epub 2013 Oct 4. PMID: 24096342; PMCID: PMC3877787.
10: Armbruster U, Labs M, Pribil M, Viola S, Xu W, Scharfenberg M, Hertle AP, Rojahn U, Jensen PE, Rappaport F, Joliot P, Dörmann P, Wanner G, Leister D. Arabidopsis CURVATURE THYLAKOID1 proteins modify thylakoid architecture by inducing membrane curvature. Plant Cell. 2013 Jul;25(7):2661-78. doi: 10.1105/tpc.113.113118. Epub 2013 Jul 9. PMID: 23839788; PMCID: PMC3753390.
11: Hertle AP, Blunder T, Wunder T, Pesaresi P, Pribil M, Armbruster U, Leister D. PGRL1 is the elusive ferredoxin-plastoquinone reductase in photosynthetic cyclic electron flow. Mol Cell. 2013 Feb 7;49(3):511-23. doi: 10.1016/j.molcel.2012.11.030. Epub 2013 Jan 3. PMID: 23290914.
12: Armbruster U, Pesaresi P, Pribil M, Hertle A, Leister D. Update on chloroplast research: new tools, new topics, and new trends. Mol Plant. 2011 Jan;4(1):1-16. doi: 10.1093/mp/ssq060. Epub 2010 Oct 5. PMID: 20924030.
13: Pribil M, Pesaresi P, Hertle A, Barbato R, Leister D. Role of plastid protein phosphatase TAP38 in LHCII dephosphorylation and thylakoid electron flow. PLoS Biol. 2010 Jan 26;8(1):e1000288. doi: 10.1371/journal.pbio.1000288. PMID: 20126264; PMCID: PMC2811158.
14: Pesaresi P, Hertle A, Pribil M, Schneider A, Kleine T, Leister D. Optimizing photosynthesis under fluctuating light: the role of the Arabidopsis STN7 kinase. Plant Signal Behav. 2010 Jan;5(1):21-5. doi: 10.4161/psb.5.1.10198. PMID: 20592803; PMCID: PMC2835952.
15: Armbruster U, Hertle A, Makarenko E, Zühlke J, Pribil M, Dietzmann A, Schliebner I, Aseeva E, Fenino E, Scharfenberg M, Voigt C, Leister D. Chloroplast proteins without cleavable transit peptides: rare exceptions or a major constituent of the chloroplast proteome? Mol Plant. 2009 Nov;2(6):1325-35. doi: 10.1093/mp/ssp082. Epub 2009 Sep 30. PMID: 19995733.
16: Pesaresi P, Hertle A, Pribil M, Kleine T, Wagner R, Strissel H, Ihnatowicz A, Bonardi V, Scharfenberg M, Schneider A, Pfannschmidt T, Leister D. Arabidopsis STN7 kinase provides a link between short- and long-term photosynthetic acclimation. Plant Cell. 2009 Aug;21(8):2402-23. doi: 10.1105/tpc.108.064964. Epub 2009 Aug 25. PMID: 19706797; PMCID: PMC2751956.
17: Reisinger V, Hertle AP, Plöscher M, Eichacker LA. Cytochrome b6f is a dimeric protochlorophyll a binding complex in etioplasts. FEBS J. 2008 Mar;275(5):1018-24. doi: 10.1111/j.1742-4658.2008.06268.x. Epub 2008 Jan 25.PMID: 18221490.