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Akt modes of stem cell regulation: more than meets the eye?

DISCOVERIES (ISSN 2359-7232),2013, October-December

CITATION:
Calautti E. Akt modes of stem cell regulation: more than meets the eye? Discoveries 2013, Oct-Dec; 1(1): e8.
DOI: 10.15190/d.2013.8

Submitted: December 22, 2013; Revised: December 30, 2013; Accepted: December 31, 2013; Published: December 31, 2013; 

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Akt modes of stem cell regulation: more than meets the eye?


MD, PhD*

Affiliation:
University of Turin, Department of Molecular Biotechnology and Health Sciences, Turin, Italy

*Corresponding author: Enzo Calautti, M.D., Ph.D; Via Nizza 52, 10126 Turin-Italy; Tel: +39-011-6706411; Fax: +39-011-6706432; E- mail: vincenzo.calautti@unito.it


Abstract

Akt signaling regulates many cellular functions that are essential for the proper balance between self-renewal and differentiation of tissue-specific and embryonic stem cells (SCs). However, the roles of Akt and its downstream signaling in SC regulation are rather complex, as Akt activation can either promote SC self-renewal or depletion in a context-dependent manner. In this review we have evidenced three “modes” of Akt-dependent SC regulation, which can be exemplified by three different SC types. In particular, we will discuss: 1) the integration of Akt signaling within the “core” SC signaling circuitry in the maintenance of SC self-renewal and pluripotency (embryonic SCs); 2) quantitative changes in Akt signaling in SC metabolic activity and exit from quiescence (hematopoietic SCs); 3) qualitative changes of Akt signaling in SC regulation: signaling compartment-talization and isoform-specific functions of Akt proteins in SC self-renewal and differentiation (limbal-corneal keratinocyte SCs). These diverse modes of action are not to be intended as mutually exclusive. Rather, it is likely that Akt proteins participate with multiple parallel mechanisms to regulation of the same SC type. We propose that under specific circumstances dictated by distinct developmental stages, differentiation programs or tissue culture conditions, one mode of Akt action prevails over the others in determining SC fates.

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News & Events Latest news from our journals.

  • 2022| Discoveries Reports

    Access the new website of DISCOVERIES REPORTS at: discoveries-reports.com. 

  • 2022, April| AWARDS!

    2022 Discoveries Award winning articles!

    - Kinal Bhatt et al. 2021 (Larking Health System, FL, USA); Bhatt K, Agolli A, Patel MH, et al. High mortality co-infections of COVID-19 patients: mucormycosis and other fungal infections. Discoveries. 2021;9(1):e126. 
    27 citations in the past 1 year - $1000 prize

    - Hasnain Jan et al. 2020 (Quaid-i-Azam University, Pakistan); Jan H, Faisal S, Khan A, et al. COVID-19: Review of Epidemiology and Potential Treatments Against 2019 Novel Coronavirus. Discoveries. 2020;8(2):e108. 
    23 citations in the past 2 years - $400 prize

    Congratulations! Prizes will be received by the awardees in July, 2022!.

  • 2021, January| AWARDS!

    2022 DISCOVERIES AWARDS! Discoveries will offer $1000 and $400 awards in early 2022, for the most cited (2021 ISI Citations) and visible (Altmetric Score) articles published in 2018-2021.

  • 2020, November| Discoveries on Twitter!

    You can now follow the latest Discoveries news and updates on Twitter! (@DiscoveriesNews) 

  • 2020, August| For Authors!

    Due to a high volume of article submissions, our peer-review process takes more than usual. The pre-screening decision is released in 1-2 days, while the peer-review process lasts between 10 and 20 days.  

  • 2020, April | For Authors!

    WE DO NOT TOLERATE ANY MISCONDUCT! Please be aware that we are testing all received articles with specialized software for PLAGIARISM and WE WILL TAKE MEASURES if your article is already published or in consideration for publication by other journals! This may result in serious professional consequences for the authors. The latest striking case is the following article which is already published and was re-submitted here.  

  • 2020, April | For Authors!

    We are happy to let you know that all articles published in Discoveries are now on PubMedCentral (PMC). New accepted articles will be included in PMC and PubMed within 1-2 weeks after their publication.

  • 2020, January | For Authors!

    Starting in January 2020, Discoveries will also consider articles submitted by Discoveries' Editorial Board members. However, only a small number of such articles (maximum 4 articles/year) will be considered for publication after the peer-review process, and the authors who are also our editors will be clearly disclosed. 

  • 2019, September | Indexed by PMC

    Discoveries is now indexed by PubMedCentral and Pubmed. The agreement with US National Library of Medicine was signed on September 10, 2019. Our next step is ISI Web of Science indexing. NOTE: previously published articles will be included on PubMed in early 2020.

  • 2019, September | PubMed inclusion!

    We are happy to let you know that Discoveries successfuly passed the last step (Technical Review) required for PubMedCentral and PubMed inclusion!

  • 2019, June | PubMed inclusion News!

    We are happy to receive positive comments from PMC/NLM-NIH regarding Discoveries' last step (Technical Review) required for PubMedCentral and PubMed inclusion. We will let you know once whole indexing process is completed. 

  • 2018-2019 | For Authors!

    From now on and for at least 1 year, we will only accept articles from authors that are NOT members of Discoveries' Editorial Board. All articles submitted by our editors will be immediately rejected until further notice. 

  • 2018 | PubMed inclusion News!

    Discoveries successfully passed the Scientific Quality Review by NLM-NIH for PubMedCentral and PubMed indexing. This is the first and the most important step towards PubMedCentral and PubMed indexing! The second (last) step is the Technical Review.

  • April 2016 | Faster Peer-Review

    Starting on April 13th, all articles selected for a peer-review will receive the post peer-review decision within 10 days. The initial pre-screening time will remain the same (48h from the submission of the manuscript). This decision will significantly accelerate the publication, with no effect on the quality of the peer-review process.

  • February 2016 | Manuscript submission

    Discoveries is commited to excellence, quality and high editorial standards. We are receiving an increasing number of manuscripts for which the identity of the authors/corresponding author can't be verified. Please NOTE that ALL these articles were and will be immediately REJECTED. Indicating an institutional email address is the easiest way to overcome this problem! Moreover, we do not accept any pressure on our editorial board to accept a manuscript. This results in a prompt rejection of the article.

    Editorial Policies
  • January 2016 |Discoveries-AIM

    After reaching all proposed milestones until now (including being indexed by Google Scholar in 2014), Discoveries' next Aim is PubMed indexing of all its articles (already published and upcoming). There will be no charge for the submission or publication of articles in Discoveries before PubMed indexing.

  • August 2015 | Discoveries - on PubMed

    We are happy to announce that our first Discoveries articles were included in PMC and PubMed. More articles (submitted by NIH funded articles) are now processed for being included.

    Discoveries articles now on PubMed
  • April 2015 | Special Issue

    DISCOVERIES publish the SPECIAL ISSUE entitled "INFLAMMATION BETWEEN DEFENSE AND DISEASE: Impact on Tissue Repair and Chronic Sickness".

    Special Issue on "Inflammation"
  • 2015 | Ischemia Collection

    DISCOVERIES launched a call for papers for a Collection of Articles with focus on "ISCHEMIA". If you are interested to submit a manuscript, please contact us at info@discoveriesjournals.org

  • October 2014 | Special Issue

    DISCOVERIES launched a call for papers, for the SPECIAL ISSUE entitled "INFLAMMATION BETWEEN DEFENSE AND DISEASE: Impact on Tissue Repair and Chronic Sickness".

  • September 2014 | Special Issue

    DISCOVERIES just publish the SPECIAL ISSUE entitled "CELL SECRETION & MEMBRANE FUSION" in September 2014. Initially scheduled for publication between October 2014-March 2015, this issue was successfully published earlier than scheduled. 

    Special Issue
  • April 2014 | Indexed by Google Scholar

    All our published articles are now indexed by Google Scholar! Current citations for each individual article published in either Discoveries or Discoveries Reports are also shown. First citations to Discoveries articles are included! Search for the article's title or the authors:

    Google Scholar Search

  • July 2013 | Manuscript Submission

    Submit your manuscript FREE, FAST and EASY ! (in less than 1 minute)
    There are NO fees for the manuscript submission or publishing of the accepted manuscripts.

    Read more

  • July 2013 | DISCOVERIES

    We are now ACCEPTING MANUSCRIPTS for publishing in DISCOVERIES. We aim to publish a small number of high impact experimental articles & reviews (around 40/year) to maintain a high impact factor. Domains of interest: all areas related to Medicine, Biology and Chemistry ...

    Read more

  • July 2013 | DISCOVERIES REPORTS

    We are now ACCEPTING MANUSCRIPTS for DISCOVERIES REPORTS, publishing inovative and important research findings from all areas related to Medicine, Biology and Chemistry. We are also accepting experimental articles that validate/invalidate highly used reagents in current publications (ex. antibodies) and selected articles presenting negative data with impact and of wide scientific interest ...

    Read more

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