Year: 2022

NUCLEAR VS MITOCHONDRIAL MUTATION. "The high mutation rate of mtDNA (~10-fold higher than nuclear DNA) and the resulting variant haplotypes may have exerted a profound influence on human radiation across the world." http://onlinelibrary.wiley.com/doi/10.1002/1873-3468.12061/full View in LinkedIn

"WHY A HIGHER MUTATION RATE occurs in the mitochondria in contrast to the nucleus appears related to the generation of genetic diversity useful in exploiting new ecological niches. In particular, the enzymes involved in energy generation by the mitochondrion. The mitochondrion is the powerhouse of the cell." http://onlinelibrary.wiley.com/doi/10.1002/1873-3468.12061/full View in LinkedIn

MITOCHONDRIAL DNA. "mtDNA variants found in different populations (haplogroups) that affect the coupling efficiency of OxPhos and ROS generation have been postulated to have had determinative effects on human migration and survival under the bioenergetic, climatic, and immunologic demands of new environments." (mtDNA = mitochondrial DNA; ROS = reactive oxygen species; OxPhos = oxidative phosphorylation). http://onlinelibrary.wiley.com/doi/10.1002/1873-3468.12061/full View in LinkedIn

DIPLOID MITOSIS VS CLONAL INHERITANCE. "Unlike the diploid genome in the nucleus which undergoes Mendelian segregation during mitosis, the mitochondrial genome is maternally inherited and therefore can be considered to be clonal in nature. The cell has multiple mitochondria, each containing multiple mtDNA copies, which undergo replicative segregation into two daughter cells." http://onlinelibrary.wiley.com/doi/10.1002/1873-3468.12061/full View in LinkedIn

MATERNAL INHERITANCE is a hallmark of the mitochondria, the highly mutating streamlined cellular powerhouse. "In mammals, sperm-derived paternal mitochondria generally enter the oocyte cytoplasm after fertilization and temporarily co-exist in the zygote alongside an excess of maternal mitochondria. Nevertheless, the paternal mitochondria and their DNA are somehow eliminated and are never transmitted to offspring." https://lnkd.in/e6EDsuy View in LinkedIn

EXTRANUCLEAR INHERITANCE IN MITOCHONDRIA. "In nuclear inheritance, genes of both male and female, present in nucleus of sperm and ovum are inherited following Mendelian principles. Recombinations possible due to meiotic crossing over. In extra nuclear inheritance, genes present in cytoplasm of ovum are inherited, Mendelian principles not followed. Recombinations not possible." https://lnkd.in/eHcDs4w View in LinkedIn

HETEROPLASMY. "Another phenomenon unique to the mitochondrial genome is the concept of heteroplasmy which arises due to the multiplicity of mtDNA copy number in each cell that can in turn give rise to a mixture of variant mtDNAs. The composition of variant mtDNAs can change over time and can differ by cell/tissue type within an individual or between individuals from the same mother, adding another dimension to mtDNA homeostasis." Not exactly clonal inheritance. http://onlinelibrary.wiley.com/doi/10.1002/1873-3468.12061/full View in LinkedIn

THE ORIGIN OF THE CHLOROPLAST is parallel in many ways to the origin of the mitochondrion. Both were a consequence of symbiosis with ancient microorganisms, both involving large gene transfers of the new organelle to the nucleus, and both remained strangely semi-autonomous. And the nucleus itself had a similar bolt-on origin. All the most important organelles of the modern cell. View in LinkedIn

"CHLOROPLASTS are essential organelles in the cells of plants and algae. The functions of these specialized plastids are largely dependent on the ~ 3000 proteins residing in the organelle. Although chloroplasts are capable of a limited amount of semiautonomous protein synthesis – their genomes encode ~ 100 proteins – they must import more than 95% of their proteins after synthesis in the cytosol." https://lnkd.in/eJUmTgD View in LinkedIn

BIOSYNTHETIC FACTORY OF PLANTS. "The chloroplast is the major organelle in plant and algal cells responsible for photosynthesis. It is also the factory in which many other essential biosynthetic reactions occur, including synthesis of amino acids, fatty acids and terpenes." http://www.sciencedirect.com/science/article/pii/S0167488912002844 View in LinkedIn