Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster E30

Role of MITF during melanocyte development as determined by a conditional mutation

Höfundar / Authors: Romain Lasseur, Eirikur Steingrimsson

Starfsvettvangur / Affiliations: Biomedical Center, Faculty of Medecine, University of Iceland

Kynnir / Presenter: Romain Lasseur

The microphthalmia-associated transcription factor (MITF) is essential for melanocyte development. However, since most of the mutations known in the mouse Mitf gene result in a complete loss of melanocytes, it has been difficult to characterize its exact role during melanocyte development. We have thus generated a conditional mutation in the mouse Mitf gene by mutating a Lysine into an Arginin in position 243 (Mitf K243R). We have used Tyr::Cre and Tyr::CreERT2 drivers to generate the mutation in vivo in melanoblasts, in vitro in mice primary melanocytes, and the Dct::LacZ reporter to track melanoblasts during development. We performed LacZ and immunofluorescent stainings on embryos to track the fate of melanoblasts. We derived melanocyte cell lines from newborn pups and extracted RNA to perform RNA-sequencing analysis. Mice homozygous for the Mitf K243R mutation have spotted coats with alternating white, grey, and black areas meaning that some melanocytes are still present. Embryos at 13 and 14 days of development have fewer melanoblasts in the truncal region. Potential MITF targets coming from the RNA-sequencing analysis will be further processed for confirmation. Our results suggest that the Mitf K243R mutation is hypomorphic. Knowing why there are fewer melanoblasts developing in early stages will be a major step into understanding the role of MITF during the development.