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HIGH FIDELITY VS DIVERSITY. Two opposing pressures in nature are, on the one hand, the need for high fidelity replication of the DNA in multicellular animals with slow reproductive rates. On the other hand is the profound drive in rapidly reproducing viruses for instance, for enormous genetic diversity and mutation to rapidly adapt to new niches. View in LinkedIn

MITOSIS. "Once the DNA and chromosomes are duplicated in S-phase, the next critical phase in cell division susceptible to genomic instability is mitosis. During mitosis, the sister chromatids are equally distributed in the daughter cells." https://lnkd.in/bam9PGn View in LinkedIn

SINGULAR EVENT. "In the S-phase, the entire genomic DNA is accurately duplicated once and only once per cell cycle. Any tendency for errors in this process would constitute genomic instability." https://lnkd.in/bam9PGn View in LinkedIn

NEXTGEN. "The ultimate goal of cell division for most non-cancerous somatic cells is to accurately duplicate the genome and then evenly divide the duplicated genome into the two daughter cells. This ensures that the daughter cells will have exactly the same genetic material as their parent cell." https://lnkd.in/bam9PGn View in LinkedIn

FIDELITY MEASURES. "During a cell division, genomic instability is minimized by four major mechanisms: high-fidelity DNA replication in S-phase, precise chromosome segregation in mitosis, error free repair of sporadic DNA damage, and a coordinated cell cycle progression." https://lnkd.in/bam9PGn View in LinkedIn

DNA BREAKS can occur in S phase of cell cycle at a rate of ~10 breaks per cell. Not including chemical and radiation forms of DNA damage. https://lnkd.in/eDr47d6 View in LinkedIn

DNA POLYMERASE plus proofreading with 1 error in 10(7) base pairs; plus mismatch repair (MMR) is 1 error in 10(9) base pairs; and with 6 X 10(9) base pairs per human genome this means only ~6 errors in the genome. https://lnkd.in/eDr47d6 View in LinkedIn

DNA POLYMERASE PROOFREADING at 1 error per 10(7) base pairs. With 6 X 10(9) base pairs in the human genome this still means 600 errors. https://lnkd.in/eDr47d6 View in LinkedIn

DNA POLYMERASE copies DNA with an error rate in copying of only 1 error per 10(5) base pairs. But the human genome has 6 X 10(9) base pairs. Thus equivalent to 60,000 errors per genome. How does the cell remedy this lopsided equation? https://lnkd.in/eDr47d6 View in LinkedIn

"THE PROTEIN UNIVERSE, a concept first mentioned in 1992, is the collection of all proteins of every biological species that lives or has lived on earth. It is a very large, poorly defined, even mysterious entity, which also happens to be an essential underpinning of all biology." https://lnkd.in/evmEhB5 View in LinkedIn