2019 Molecular plant physiology LECTURE NOTES UNIVERSITY OF SZEGED www.u-szeged.hu EFOP-3.4.3-16-2016-00014 This teaching material has been made at the University of Szeged, and supported by the European Union. Project identity number: EFOP-3.4.3-16-2016-00014 MOLECULAR PLANT PHYSIOLOGY lecture notes Edited by: Prof. Dr. Attila Fehér Written by: Prof. Dr. Attila Fehér Dr. Jolán Csiszár Dr. Ágnes Szepesi Dr. Ágnes Gallé Dr. Attila Ördög © 2019 Prof. Dr. Attila Fehér, Dr. Jolán Csiszár, Dr. Ágnes Szepesi, Dr. Ágnes Gallé, Dr. Attila Ördög The text can be freely used for research and education purposes but its distribution in any form requires written approval by the authors. University of Szeged 13. Dugonics sq., 6720 Szeged www.u-szeged.hu www.szechenyi2020. Content Preface ..................................................................................................................................................... 5 Expected learning outputs ...................................................................................................................... 6 Chapter 1. The organization and expression of the plant genome ......................................................... 7 1.1. Organization of plant genomes .................................................................................................... 8 1.2.2. Structure of the chromatin .................................................................................................... 9 1.2. The plant genes .......................................................................................................................... 10 1.3. Regulation of the gene expression ............................................................................................. 11 1.3.1. General features .................................................................................................................. 11 1.3.2. Cis-acting regulatory elements ............................................................................................ 12 1.3.3. Transcription factors ........................................................................................................... 12 1.3.4. The heterochromatic small interfering RNAs ...................................................................... 13 1.4. Other mechanisms controlling gene expression ........................................................................ 14 1.4.1 Post-transcriptional regulations ........................................................................................... 14 1.4.2. Post-translational regulations ............................................................................................. 14 Chapter 2. An introduction to plant cells .............................................................................................. 19 2. 1. Plant cell wall ............................................................................................................................. 20 2.1.1. The primary cell wall ........................................................................................................... 20 2.1.2. Secondary cell wall .............................................................................................................. 20 2.2. Membranes of the Cell-Endomembrane System ....................................................................... 20 2.2.1. Plasmodesmata ................................................................................................................... 20 2.2.2. Vacuoles .............................................................................................................................. 21 2.2.3. Endoplasmic reticulum (ER)................................................................................................. 21 2.2.5. Golgi apparatus ................................................................................................................... 22 2.2.6. Trans Golgi network (TGN) .................................................................................................. 23 2.2.7. Microbodies ......................................................................................................................... 23 2.3. The nucleus ................................................................................................................................. 23 2.4. Mitochondria .............................................................................................................................. 24 2.5. Plastids ........................................................................................................................................ 25 2.5.1. Proplastid ............................................................................................................................. 25 2.5.2. Etioplasts ............................................................................................................................. 25 2.5.3. Leucoplasts .......................................................................................................................... 25 2.5.4. Chromoplasts ....................................................................................................................... 26 2.5.5. Gerontoplasts ...................................................................................................................... 26 2.5.6. Chloroplasts ......................................................................................................................... 26 2.6. Plant Cytoskeleton ...................................................................................................................... 27 Chapter 3. Mineral nutrition ................................................................................................................. 31 3.1. Nutrients ..................................................................................................................................... 31 3.2. Liebig’s law of the minimum and Mitscherlich’s law of diminishing returns ............................. 32 3.3. Mineral content of plant material .............................................................................................. 34 3.4. Soil .............................................................................................................................................. 34 3.5. PH dependence of nutrient uptake ............................................................................................ 35 3.6. Nutrient deficiency ..................................................................................................................... 35 3.7. The most important elements for plants ................................................................................... 39 3.7.1. Nitrogen ............................................................................................................................... 39 3.7.2. Sulphur ................................................................................................................................ 39 3.7.3. Phosphorus .......................................................................................................................... 39 3.7.4. Potassium ............................................................................................................................ 40 3.7.5. Calcium ................................................................................................................................ 40 3.7.6. Magnesium .......................................................................................................................... 40 3.7.7. Iron ...................................................................................................................................... 41 Chapter 4. Short and long distance transport ....................................................................................... 44 4.1. Chemical potential of water ....................................................................................................... 44 4.2. Water potential and water potential gradients ......................................................................... 45 4.3. Water movement within plant body .......................................................................................... 46 4.4. Chemical potential of solutes ..................................................................................................... 48 4.5. Membrane transport: pumps, carriers, channels ...................................................................... 49 Chapter 5. Photosynthesis, the source of life on the Planet Earth ....................................................... 53 5.1. Utilization of light energy, photosynthetic organisms, general equation of photosynthesis .... 54 5.2. Structure of the photosynthetic apparatus: chloroplasts, pigments, light absorption and excitation ........................................................................................................................................... 55 5.3. Operation of photosynthetic electron transport chain .............................................................. 58 5.4. Synthesis and export of stable products .................................................................................... 59 Chapter 6. Plant hormones ................................................................................................................... 64 6.1. Definition and general characteristics of plant hormones ........................................................