miR-30 microRNA precursor is a small non-coding RNA

Non-coding RNA

A non-coding RNA is a functional RNA molecule that is not translated into a protein. Less-frequently used synonyms are non-protein-coding RNA , non-messenger RNA and functional RNA . The term small RNA is often used for short bacterial ncRNAs...

 that regulates gene expression

Gene expression

Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as ribosomal RNA , transfer RNA or small nuclear RNA genes, the product is a functional RNA...

. Animal microRNAs are transcribed as ~70 nucleotide

Nucleotide

Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...

 stem-loop

Stem-loop

Stem-loop intramolecular base pairing is a pattern that can occur in single-stranded DNA or, more commonly, in RNA. The structure is also known as a hairpin or hairpin loop. It occurs when two regions of the same strand, usually complementary in nucleotide sequence when read in opposite directions,...

 precursor and subsequently processed by the Dicer

Dicer

Dicer is an endoribonuclease in the RNase III family that cleaves double-stranded RNA and pre-microRNA into short double-stranded RNA fragments called small interfering RNA about 20-25 nucleotides long, usually with a two-base overhang on the 3' end...

 enzyme to give a mature ~22 nucleotide product. In this case the mature sequence comes from both the 3' (miR-30) and 5' (mir-97-6) arms of the precursor. The products are thought to have regulatory roles through complementarity to mRNA .

A screen of 17 miRNAs that have been predicted to regulate a number of breast cancer associated genes found variations in the microRNAs
miR-17

Mir-17 microRNA precursor family

The miR-17 microRNA precursor family are a group of related small non-coding RNA genes called microRNAs that regulate gene expression. The microRNA precursor miR-17 family, includes miR-20, miR-91, and miR-103. miRNAs are transcribed as ~70 nucleotide precursors and subsequently processed by the...

 and miR-30c-1, these patients were noncarriers of BRCA1

BRCA1

BRCA1 is a human caretaker gene that produces a protein called breast cancer type 1 susceptibility protein, responsible for repairing DNA. The first evidence for the existence of the gene was provided by the King laboratory at UC Berkeley in 1990...

 or BRCA2

BRCA2

BRCA2 is a protein that in humans is encoded by the BRCA2 gene.BRCA2 orthologs have been identified in most mammals for which complete genome data are available....

 mutations, lending the possibility that familial breast cancer may be caused by variation in these miRNAs.

Members of the miR-30 family have been found to be highly expressed in heart cells.

Targets of miR-30

It has been shown that the integrin ITGB3 and the ubiquitin conjugating E2 enzyme UBC9 are downregulated by miR-30. It has also been suggested that the TP53 protein may be a target of miR-30c and miR-30e. An immunoblot analysis revealed that p53 expression levels were elevated upon knockdown of miR-30c and miR-30e.