LncRNAs determine the fate of stem cells, tissue type's identity, organ function, and even body plan
Excerpt: "Pluripotent stem cells have broad applications in regenerative medicine and offer ideal models for understanding the biological process of embryonic development and specific diseases. Studies suggest that the self-renewal and multi-lineage differentiation of stem cells are regulated by a complex network consisting of transcription factors, chromatin regulators, signaling factors, and non-coding RNAs. It is of great interest to identify RNA regulatory factors that determine the fate of stem cells. Long non-coding RNA (lncRNA), a class of non-coding RNAs with more than 200 bp in length, has been shown to act as essential epigenetic regulators of stem cell pluripotency and specific lineage commitment. In this review, we focus on recent research progress related to the function and epigenetic mechanisms of lncRNA in determining the fate of stem cells, particularly pluripotency maintenance and lineage-specific differentiation."
My comment: LncRNAs regulate e.g. cellular differentiation processes.
Excerpt: "Long non-coding RNAs (lncRNAs) are a large class of gene transcripts that do not code proteins; however, their functions are largely unknown and many new lncRNAs are yet to be discovered. Taking advantage of our previously developed, super-fast, novel lncRNA discovery pipeline, UClncR, and rich resources of GTEx RNA-seq data, we performed systematic novel lincRNA discovery for over 8000 samples across 30 tissue types. We conducted novel detection for each major tissue type first and then consolidated the novel discoveries from all tissue types. These novel lincRNAs were profiled and analyzed along with known genes to identify tissue-specific genes in 30 major human tissue types. Thirteen sub-brain regions were also analyzed in a similar manner. Our analysis revealed thousands to tens of thousands of novel lincRNAs for each tissue type. These lincRNAs could define each tissue type’s identity and demonstrated their reliability and tissue-specific expression."
Excerpt: "Long non-coding RNAs (lncRNAs) are important biological mediators that regulate numerous cellular processes. New experimental evidence suggests that lncRNAs play essential roles in liver development, and normal liver physiology"
My comment: LncRNAs also regulate organ development and function.
https://academic.oup.com/mbe/article/32/9/2367/1030095
Excerpt: "A high diversity of transiently expressed lncRNAs also was present during the first 24 h of metamorphosis, when the larval body plan is being resculpted into the juvenile/adult body plan. Finally, the number of expressed lncRNAs increased at the establishment of the juvenile body plan and in the adult."
My comment: LncRNAs are involved even in the regulation of body plans.
The number of DIFFERENT lncRNAs in a human body according to NONCODEv5 is 172,216. However, the number of different lncRNAs in a chimp body is only 18,604. LncRNAs play a very significant role in cellular differentiation, tissue type regulation, organ function, and even body plan. We should also remember that the number of different lncRNAs in a human body is almost 9 times higher than the number of protein-coding genes. Studies have also revealed that human/chimp lncRNAs are very different (non-conserved). Evolution believers claim that lncRNAs have evolved through mutations (HAR = human accelerated regions). However, medical science is aware that lncRNAs don't tolerate mutations:
https://www.qmul.ac.uk/blizard/about/news/items/long-noncoding-rnas-in-neurological-diseases.html
Excerpt: "Because of their important role in gene expression regulation, it should not be surprising to assume that any malfunction of lncRNAs, for example due to mutations, could have even serious consequences on the normal development of body organs. In fact, this is exactly what has been found by comparing the sequences of these RNAs in normal people versus diseased individuals.
In the field of neurology, mutations in lncRNAs have been associated with abnormalities of neurological development or neurodegenerative diseases such as Alzheimer’s, Parkinson’s, Huntington’s and ASD (Autism spectrum disorder). Given the high personal and social impact of these diseases, it is very important to understand how these RNAs carry out their activity and what goes wrong following disease-causing mutations."
Summary and conclusions:
- LncRNAs have a crucial epigenetic role in several cellular processes such as stem cell differentiation, tissue type regulation, organ function, and body plan.
- DNA doesn't determine stem cell fate, tissue type, organ function, or body plan. DNA is passive information used in a sophisticated way for the cell to construct active RNA molecules.
- The number of different lncRNAs in a human body is almost 9-fold compared to that of chimps.
- It's ridiculous to claim that this huge difference in the number of human lncRNAs could have arisen after a chromosome fusion because biological information is always reduced during chromosome fusions.
- LncRNAs don't tolerate mutations. It's impossible for lncRNAs to evolve through mutations. Science is not aware of positive mutations in these regulatory lncRNAs.
- We are not related to chimps.
