KEY POINTS * Embryonic and adult tissue stem cells are characterized by their ability to self-renew and to differentiate into daughter cells, which in adult tissue stem cells is often

achieved by asymmetric divisions. * MicroRNAs (miRNAs) are 20–25-nucleotide (nt)-long non-coding RNAs that bind to the 3′ untranslated region of target mRNAs via imperfect match to repress

their translation and stability. * miRNAs fine-tune self-renewal and differentiation pathways of stem cells by regulating the intracellular levels of the key protein factors that are

involved in these processes. It is now clear that a number of miRNAs that are involved in stem cell processes are co-expressed as clusters and can function as 'master regulators'

sequencing technologies has increased our ability to identify new miRNAs and other small RNAs in various tissues. ABSTRACT The hallmark of a stem cell is its ability to self-renew and to

produce numerous differentiated cells. This unique property is controlled by dynamic interplays between extrinsic signalling, epigenetic, transcriptional and post-transcriptional

regulations. Recent research indicates that microRNAs (miRNAs) have an important role in regulating stem cell self-renewal and differentiation by repressing the translation of selected mRNAs

in stem cells and differentiating daughter cells. Such a role has been shown in embryonic stem cells, germline stem cells and various somatic tissue stem cells. These findings reveal a new

dimension of gene regulation in controlling stem cell fate and behaviour. Access through your institution Buy or subscribe This is a preview of subscription content, access via your

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* Learn about institutional subscriptions * Read our FAQs * Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS NEW INSIGHTS INTO THE EPITRANSCRIPTOMIC CONTROL OF PLURIPOTENT

STEM CELL FATE Article Open access 21 October 2022 EPITRANSCRIPTOMIC MODIFICATIONS IN MESENCHYMAL STEM CELL DIFFERENTIATION: ADVANCES, MECHANISTIC INSIGHTS, AND BEYOND Article 20 November

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Article  CAS  Google Scholar  Download references ACKNOWLEDGEMENTS We thank members of the Lin laboratory for their valuable comments on the manuscript. We apologize to those whose works are

not cited here owing to space limitations. The stem cell work done in the Lin laboratory is supported by National Institutes of Health Grants HD33760, HD37760S1 and HD42042, the Connecticut

Stem Cell Research Fund, the G. Harold and Leila Mathers Foundation and the Stem Cell Research Foundation. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Yale Stem Cell Center, Yale

University School of Medicine, 10 Amistad Street, Room 220, New Haven, 06520-8002, Connecticut, USA Vamsi K. Gangaraju & Haifan Lin Authors * Vamsi K. Gangaraju View author publications

You can also search for this author inPubMed Google Scholar * Haifan Lin View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR

Correspondence to Haifan Lin. RELATED LINKS RELATED LINKS DATABASES THE MIRNA REGISTRY let-7 miR-1 miR-15b miR-16 miR-17 miR-20a miR-21 miR-22 miR-23 miR-24 miR-26a miR-29 miR-106a miR-124

miR-125b miR-128 miR-133 miR-134 miR-144 miR-150 miR-155 miR-181 miR-203 miR-206 miR-221 miR-222 miR-223 miR-290 miR-296 miR-301 miR-302 miR-424 miR-451 miR-470 FURTHER INFORMATION Haifan

Lin's homepage GLOSSARY * Blastocyst An early stage of embryonic development at which cells begin to commit to two developmental lineages: the inner cell mass, which gives rise to the

fetus, and the trophoblast, which gives rise to fetal support tissues, such as the placenta and the umbilical cord. * Niche The natural anatomical microenvironment that supports stem cell

behaviour. * Spliceosome A ribonucleoprotein (RNP) complex that is involved in splicing of nuclear pre-mRNA. It is composed of five small nuclear (sn) RNPs and more than 50 non-snRNPs, which

recognize and assemble on exon–intron boundaries to catalyse intron processing of the pre-mRNA. * Piwi An Argonaute or Piwi protein family member in _Drosophila melanogaster_ that is

required for germline stem cell self-renewal and also binds to ∼25 nucleotide small RNAs. Piwi is the founding member that was used to define the protein family. * Transposon A mobile

genetic element that can relocate within the genome of its host. An autonomous transposon encodes a transposase protein that catalyses its excision and reintegration in the genome, and can

therefore direct its own transposition. * Gap junction An intercellular connection that directly connects cytoplasm of two cells so that exchange of molecules and ions can occur freely. *

Neoblast An undifferentiated cell in annelids that proliferates to produce differentiated cells at the sites of repair. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE

CITE THIS ARTICLE Gangaraju, V., Lin, H. MicroRNAs: key regulators of stem cells. _Nat Rev Mol Cell Biol_ 10, 116–125 (2009). https://doi.org/10.1038/nrm2621 Download citation * Issue Date:

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