2016/12/27

Long non-coding RNAs regulate cellular processes - NO JUNK DNA

The important role of long non-coding RNAs regulating cellular processes - There is no JUNK-DNA


Excerpt: "Scientific research over the past decade has concentrated almost exclusively on the 2 percent of the genome's protein coding regions, virtually ignoring the other 98 percent, a vast universe of non-coding genetic material previously dismissed as nothing more than 'junk.' Now, a team led by investigators at Beth Israel Deaconess Medical Center (BIDMC) reveals that one type—called long non-coding RNA (lncRNA)—may be critically important for controlling cellular components in a tissue-specific manner. Published online today in the journal Nature, the new research points to an lncRNA's key role in helping control processes related to muscle regeneration and cancer.
Long non-coding RNAs appear to be transcribed from our DNA in a similar manner to coding messenger RNAs but are not translated into proteins. While lncRNA molecules do not produce correspondingly lengthy proteins, researchers have wondered whether some of these molecules may contain segments of sequences that can code for very short proteins, or polypeptides.
"Whether such small, hidden polypeptides are actually functional, or represent 'translational noise' within the cell is still relatively unclear," said senior author Pier Paolo Pandolfi, MD, PhD, Director of the Cancer Center and Cancer Research Institute at BIDMC. "Our team set about trying to understand to what extent lncRNA molecules might actually encode functional polypeptides, and how important such peptides might be."
The investigators used computational analyses to predict potential polypeptides that could be encoded by known lncRNA molecules, and then they used mass spectrometry to determine if these putative polypeptides were actually expressed. "With this approach we actually identified many expressed hidden polypeptides and went on to characterize one in particular," Pandolfi explained. This specific lncRNA molecule is termed LINC00961 and encodes a 90 amino acid polypeptide.
A variety of molecular and biochemical experiments revealed that the LINC00961 encoded polypeptide played an important role in modulating the activity of the mTORC1 protein complex, which is a critical sensor of nutrient availability within cells. The complex also regulates a variety of cellular processes including translation, metabolism, cell growth, and proliferation, and alterations in its function can lead to diseases such as cancer. Because the LINC00961 polypeptide appeared to specifically block mTORC1's ability to sense stimulation with amino acids, the investigators named the peptide encoded by the lncRNA SPAR (Small regulatory Polypeptide of Amino acid Response)."

My comment:

1. Non coding RNAs covers about 98% of the whole genome within humans, for example. And because their role seems to be very important for cellular processes it should be taken seriously when comparing human and chimp genomes. At the whole genome level, the similarity between human and chimp DNA is not even close to 98%. Will evolutionary industry correct that old lie in near future? We'll see.

2. It should also correct the old lie of the evolutionary junk-DNA. Obviously there is no junk in any DNA within any organism.

3. Non-coding RNAs regulate several significant jobs the cells are doing. Because they regulate translation, it's likely that they are able to override and repair errors in gene sequences. This is why random mutations, errors and mistakes, have no role in ecological adaptation. Erroneous alterations in the function of non-coding RNAs can lead to diseases, such as cancer.
4. Non-coding RNAs don't give support for the evolutionary theory. They point out that genes are not driving the ecological adaptation. Genes are followers, not leaders. They are raw material for RNA-mediated cellular processes. Non-coding RNAs are NOT copied from the DNA, instead they are programmed by very complex energy dependent mechanisms.