Date(s) : 11/05/2016 iCal
11 h 00 min - 12 h 00 min
Nucleotide sequences, such as rRNA genes, are multi-tasked, beyond ‘known’ function, i.e. coding for the protein ribin .
Regular protein coding genes might actually code for several widely different proteins due to:
(a) translational activity by stop-suppressor tRNAs [2,3](b) tRNAs with expanded codons [4,5](c) Systematic transcriptional transformations alter coding and other properties of RNAs, such as systematic deletions after each trinucleotide,
or systematic nucleotide exchanges (e.g. A<->G) over complete genes [6,7].
Human mitochondrial RNAs sequenced by classical and next generation methods match various transformations.
Peptides matching specifically detected transformed RNAs occur in human mass spectrometry mitoproteomic data [8,9], have also been detected by monoclonal antibodies .
Alternative transcriptions and translations explain trashed -omic data, increasing considerably coding potential.
1. Barthélémy RM, Grino M, Casanova J-P, Faure E 2010 Ribin-like proteins expression in the chaetognath Spadella cephaloptera. Int J Genet Mol Biol 2, 20–29.
2. Capone JP, Sharp PA, RajBhandary UL 1985 Amber, ochre and opal suppressor tRNA genes derived from a human serine tRNA gene. Embo J 4, 213-221.
3. Seligmann H 2010 Avoidance of antisense antiterminator tRNA anticodons in vertebrate mitochondria. Biosystems 101, 42-50.
4. Riddle DL, Roth JR 1972 Frameshift suppressors. 3. Effects of suppressor mutations on transfer RNA. J Mol Biol 66, 495-506.
5. Seligmann H 2012 Putative mitochondrial polypeptides coded by expanded quadruplet codons, decoded by antisense tRNAs with unusual anticodons. Biosystems 110, 84-106.
6. Seligmann H 2013a Polymerization of non-complementary RNA: systematic symmetric nucleotide exchanges mainly involving uracil produce mitochondrial RNA transcripts coding for cryptic overlapping genes. Biosystems 111, 156-174.
7. Seligmann H 2013b Systematic asymmetric nucleotide exchanges produce human mitochondrial RNAs cryptically encoding for overlapping protein coding genes. J Theor Biol 324, 1-20.
8. Seligmann H 2015 Codon expansion and systematic transcriptional deletions produce tetra-, pentacoded mitochondrial peptides. J Theor Biol 387, 154-165.
9. Translation of mitochondrial swinger RNAs according to tri-, tetra- and pentacodons. Biosystems 140, 38-48.
10. Faure E, Delaye L, Tribolo S, Levasseur A, Seligmann H, Barthélémy R-M 2011 Probable presence of an ubiquitous cryptic mitochondrial gene on the antisense strand of the cytochrome oxidase I gene. Biology Dir 6, 56.