Comprehensive survey of human brain microRNA by deep sequencing.
BACKGROUND
MicroRNA (miRNA) play an important role in gene expression regulation. At present, the number of annotated miRNA continues to grow rapidly, in part due to advances of high-throughput sequencing techniques. Here, we use deep sequencing to characterize a population of small RNA expressed in human and rhesus macaques brain cortex.


RESULTS
Based on a total of more than 150 million sequence reads we identify 197 putative novel miRNA, in humans and rhesus macaques, that are highly conserved among mammals. These putative miRNA have significant excess of conserved target sites in genes' 3'UTRs, supporting their functional role in gene regulation. Additionally, in humans and rhesus macaques respectively, we identify 41 and 22 conserved putative miRNA originating from non-coding RNA (ncRNA) transcripts. While some of these molecules might function as conventional miRNA, others might be harmful and result in target avoidance.


CONCLUSIONS
Here, we further extend the repertoire of conserved human and rhesus macaque miRNA. Even though our study is based on a single tissue, the coverage depth of our study allows identification of functional miRNA present in brain tissue at background expression levels. Therefore, our study might cover large proportion of the yet unannotated conserved miRNA present in the human genome.
Shao
Ning-Yi
NY
Partner Institute for Computational Biology, 320 Yueyang Road, 200031 Shanghai, China.
Hu
Hai Yang
HY
Yan
Zheng
Z
Xu
Ying
Y
Hu
Hao
H
Menzel
Corinna
C
Li
Na
N
Chen
Wei
W
Khaitovich
Philipp
P
D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism*; D017124:Conserved Sequence; D020869:Gene Expression Profiling; D006801:Humans; D008253:Macaca mulatta / Q000235:genetics; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D017397:Prefrontal Cortex / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000379:methods*
D035683:MicroRNAs; D022661:RNA, Untranslated