Mir-34 microRNA precursor family
The miR-34 microRNA precursor family are non-coding RNA molecules that, in mammals, give rise to three major mature miRNAs. The miR-34 family members were discovered computationally and later verified experimentally. The precursor miRNA stem-loop is processed in the cytoplasm of the cell, with the predominant miR-34 mature sequence excised from the 5' arm of the hairpin.
The miR-34 family
In mammals, three miR-34 precursors are produced from two transcriptional units. The human miR-34a precursor is transcribed from chromosome 1. The miR-34b and miR-34c precursors are co-transcribed from a region on chromosome 11, apparently as part of a transcript known as .Expression of MIR34A (gene) in mouse is observed in all tissues examined but is highest in brain. miR-34b and -c are relatively less abundant in most tissues, but are the predominant miR-34 species in lung. The presence of miR-34 products has also been confirmed in embryonic stem cells. miR-34 has been shown to be maternally inherited in Drosophila and zebrafish and the loss of miR-34 resulted in defects in hindbrain development in zebrafish embryos. This was the first report of knockdown phenotype of miR-34 in any model organism although the phenotype was observed in only about 30% of zebrafish embryos.
Targets of miR-34
Yamakuchi et al.. showed that miR-34a targets the silent information regulator 1 gene:Recently Quantitative proteomics – SILAC approach was used to identify miR-34a targets at genome level in HEK293T cells.