For the first time, researchers at the Max Planck Institute of Molecular Plant Physiology in Potsdam (Germany) examined chloroplast inheritance under a variety of environmental conditions.
Contrary to popular belief, paternal chloroplasts can be transmitted to offspring under cold conditions, whereas maternal chloroplasts are not.
Thus, maternal and paternal chloroplasts meet in the offspring and may be able to exchange genetic material.
The new findings may allow plant breeders to use chloroplast genetic material to selectively use traits for the first time.
Chloroplast from the father
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When plants reproduce, the sperms contained within pollen grains fuse with the egg cell contained within the flower on which the pollen has landed, as per ScienceDaily.
In this way, the genetic material of both parents' cell nuclei is combined in the seed.
This is significant because it allows harmful mutations to be purged from the genetic material, which would otherwise accumulate over generations.
Aside from the genetic material found in the cell nucleus, mitochondria and chloroplasts also contain genetic material.
Mitochondria are the cell's combustion engines. Animal and plant cells use them to burn carbohydrates and use the energy released for metabolism.
Chloroplasts are also found in plants. They contain the green pigment chlorophyll and serve as the cells' solar power plants.
Plants use chloroplasts to collect solar energy and use it to produce carbohydrates in a process known as photosynthesis.
Mitochondria and chloroplasts have their genetic material because they are descended from bacteria that were consumed by the ancestors of modern animal and plant cells over a billion years ago.
Mitochondria and chloroplasts have developed a symbiotic relationship within the cell, and the former roommates are now essential for plant survival.
It is well known that, unlike the genetic material in the cell nucleus, the genomes of mitochondria and chloroplasts are not inherited equally from the father and mother.
Both are almost entirely passed down by the mother because they either do not enter the sperm at all or have their genetic material degraded in the pollen.
If the mother and father's mitochondria and chloroplasts never meet, they cannot have sex to exchange genetic material.
As a result, harmful genetic mutations will accumulate over generations, eventually leading to genome collapse.
Tobacco plants, contrary to popular belief, can routinely pass on chloroplasts from the father plant under certain environmental conditions, according to researchers at the Max Planck Institute of Molecular Plant Physiology.
The researchers first created father plants with antibiotic-resistant chloroplasts. During pollen maturation, these plants were subjected to a variety of environmental conditions such as heat, cold, drought, and bright light.
These plants' pollen was used to pollinate unmodified mother plants.
This cross's seeds were grown in a culture medium containing the appropriate antibiotic.
Because only paternal chloroplasts survive in this medium, cells containing chloroplasts from the father plant appear green, whereas plants with only maternally inherited chloroplasts appear pale, as these chloroplasts bleach out due to antibiotic sensitivity.
Due to the rarity of paternally inherited chloroplasts, the scientists had to examine nearly four million seedlings to demonstrate that the proportion of paternally inherited chloroplasts was 150 times higher under cold treatment than under normal temperature.
Chloroplasts are plant cell organelles that use photosynthetic energy to convert light energy into relatively stable chemical energy, as per Frontiers.
They sustain life on Earth by doing so.
Chloroplasts also support plant cells' metabolic activities, such as the synthesis of fatty acids, membrane lipids, isoprenoids, tetrapyrroles, starch, and hormones.
Chloroplast biogenesis, morphogenesis, protection, and senescence are critical for maintaining chloroplast structure and function.
Furthermore, chloroplasts are surrounded by two membranes that include a third complex membrane system, the thylakoids, which include grana and lamellae.
Starch grains, plastoglobules, stromules, eyespots, pyrenoids, and other chloroplast structures are also important.
Chloroplasts are widely thought to have evolved from a free-living photosynthetic cyanobacterium that was engulfed by a eukaryotic cell.
The majority of chloroplast proteins are encoded by nuclear genes, and the gene products are transported into the chloroplast via complex import machinery.
The coordination of nuclear and plastid genome expression forms the foundation for both anterograde and retrograde signaling pathways.
Proplastids and etioplastids differentiate into chloroplasts as the leaf develops from the shoot apical meristem.
Chloroplasts are divided by a massive protein complex known as the plastid-dividing (PD) machinery, and their division is also regulated by a variety of factors to achieve the optimal number and size of chloroplasts in the cell.
These processes are critical for chloroplast biogenesis and three-dimensional dynamic structure.
Reactive oxygen species (ROS) and other cellular signals can be produced during photosynthesis.
The chloroplast, as an important metabolic hub of the plant cell, is critical for a variety of abiotic and biotic stresses, including drought, high light, cold, heat, oxidative stresses, phosphate deprivation, and programmed cell death at infection sites.
