Title:Fragmentation and Matching of Human MicroRNA Sequences in 3’utr
VOLUME: 9 ISSUE: 5
Author(s):Michael S. Parker, Ambikaipakan Balasubramaniam, Floyd R. Sallee and Steven L. Parker*
Affiliation:Department of Microbiology and Molecular Cell Sciences, University of Memphis, Memphis TN 38152, Department of Surgery, University of Cincinnati School of Medicine, Cincinnati, OH 42567, Department of Psychiatry, University of Cincinnati School of Medicine, Cincinnati OH 42567, Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163
Keywords:microRNA phylogeny, simian microRNAs, microRNA mRNA segments, sense matching, antisense matching,
miR-619-5p.
Abstract:
Aims: Definition of sense and antisense microRNA matches in 3’utr.
Background: Matches of mature microRNAs (m-miRs) in human 3’utr could be traced to mutations
producing fragments of original m-miR sequences without physical separation. (The m-miR
matches in 5’utr and cds should be by far fewer, but could follow similar patterns).
Objective: To ascertain if the sense and antisense m-miR fragments in 3’utr occur at similar or different
levels.
Methods: Frequency of sense and antisense m-miR matches in 3'utr was examined in the range of
7-22 nucleotides.
Results: The fragmentation occurs at gene level by mutation within one of the paired m-miRs,
which upon transcription results in increased interactive capability for both former pre-micro (premir)
RNA stem partners. The non-mutated stem partner can persist in 3’utr sequences, as is apparent
from significant presence of miR-619-5p and miR-5096 and some conservation of 20 other
simian- specific m-miR sequences. However, most of m-mir sequences in 3’utr are extensively
fragmented, with low preservation of long matches. In flanks of individual m-miR embeds the mutated
pre-mir positions are to a degree defined specifically.
Conclusion: The m-mir matches of various sizes in 3’utr apparently reflect accumulation, on a phylogenetic
time scale, of in-sequence point mutations. Across human 3’utr this fragmentation is significantly
less for evolutionarily recent human m-miRs that originate in simians compared to human
m-miRs first appearing in lower primates, and especially to human m-miRs introduced in nonprimates.