Month: September 2022

NON-CODING DNA. “This apparent paradox was resolved by the discovery that the genomes of most eukaryotic cells contain not only functional genes but also large amounts of DNA sequences that do not code for proteins. The difference in the sizes of the salamander and human genomes thus reflects larger amounts of non-coding DNA, rather than more genes, in the genome of the salamander." https://lnkd.in/d3J4fHw View in LinkedIn

COMPLEXITY RELATES TO NON-CODING DNA. “The presence of large amounts of noncoding sequences is a general property of the genomes of complex eukaryotes. Thus, the thousandfold greater size of the human genome compared to that of E. coli is not due solely to a larger number of human genes." Remember "junk DNA"? https://lnkd.in/d3J4fHw View in LinkedIn

NON-CODING IMPORTANCE. "The human genome is thought to contain approximately 100,000 genes—only about 25 times more than E. coli has. Much of the complexity of eukaryotic genomes thus results from the abundance of several different types of noncoding sequences, which constitute most of the DNA of higher eukaryotic cells." https://lnkd.in/d3J4fHw View in LinkedIn

PARALLEL DEVELOPMENT. "Current complexity of human physiology cannot be solely explained by expression of 20000 protein-coding genes, comparable to that observed in Drosophila melanogaster and Caenorhabditis elegans, but rather by parallel development of a noncoding genome." https://lnkd.in/d2sxUZQ View in LinkedIn

COMPLEXITY. "Unlike proteome, amount of ncRNAs has increased during evolution and it seems to be a significant correlation between lncRNAs expression levels and complexity, explaining that primates have most lncRNAs. The number of protein-coding genes cannot explain functioning of very finely regulated organs such as brain." (ncRNA = non coding RNA; IncRNA = long non coding RNA). https://lnkd.in/d2sxUZQ View in LinkedIn

EXPANDED ADAPTIVE CAPACITY. "LncRNAs could then be considered as molecular sensors of environmental changes conferring evolutional plasticity that contributes to development of life complexity. During environmental changes, lncRNAs located within intergenic sequences may serve as supports for new functions allowing body to adapt new constraints." (IncRNA = long non coding RNA). https://lnkd.in/d2sxUZQ View in LinkedIn

DNA --> mRNA --> PROTEIN DOGMA. "The central dogma of gene expression is that DNA is transcribed into messenger RNAs, which in turn serves as the template for protein synthesis. The discovery of extensive transcription of large RNA transcripts that do not code for proteins, termed long noncoding RNAs (lncRNAs) provide an important new perspective on the centrality of RNA in gene regulation." https://lnkd.in/dCi-e6y View in LinkedIn

CENTRAL DOGMA. "Mammalian proteins are expressed at ∼10(3) to 10(8) molecules per cell. Differences between cell types, between normal and disease states, and between individuals are largely defined by changes in the abundance of proteins, which are in turn determined by rates of transcription, messenger RNA (mRNA) degradation, translation, and protein degradation." https://lnkd.in/dsCRAbW View in LinkedIn

DOGMA. "If the rates for one of these steps differ much more than the rates of the other three, that step would be dominant in defining the variation in protein expression. Over the past decade, system-wide studies have claimed that in animals, differences in translation rates predominate." http://science.sciencemag.org/content/347/6226/1066 View in LinkedIn

CENTRAL DOGMA RECALIBRATED. "Recent studies "challenge this conclusion, suggesting that transcriptional control makes the larger contribution." http://science.sciencemag.org/content/347/6226/1066 View in LinkedIn