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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

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

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

BURSTS OF DIVERSIFICATION. "Gene transfer from bacteria to eukaryotes is episodic and coincides with major evolutionary transitions at the origin of chloroplasts and mitochondria." https://lnkd.in/ePgs9VJ 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

COMPLEX CO-EVOLUTION. "As they co-evolved with their host cells, the original endosymbionts lost most of their genetic repertoires, either definitively or through transfer to the host’s nuclear genome. In parallel, having picked up suitable signal sequences, the products of many nuclear genes of endosymbiotic origin were re-routed back to their original compartment, together with new nucleus-encoded proteins, via intracellular trafficking routes." https://lnkd.in/ePgs9VJ 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

FOSSIL RELIC OR CLEAR STRATEGY? "Chloroplasts contain their own genome that is a relic of the endosymbiont that gave rise to the organelle. The coding capacity of the plastome is limited, it only encodes 75–80 proteins of the 3500–4000 proteins present in the chloroplast." https://lnkd.in/ewFu3YE View in LinkedIn

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

BEYOND STREAMLINING. "The genome of extant chloroplasts encodes only ~ 100 proteins. Accordingly, more than 95% of chloroplast proteins are nuclear encoded, synthesized in the cytoplasm as precursor proteins and post-translationally imported into the plastids." http://www.sciencedirect.com/science/article/pii/S0167488912002844 View in LinkedIn