Rosa-Garrido M.,Fundacion Marques Of Valdecilla Institute Formacion E Investigacion Marques Of Valdecilla |
Rosa-Garrido M.,University of Cantabria |
Ceballos L.,Fundacion Marques Of Valdecilla Institute Formacion E Investigacion Marques Of Valdecilla |
Ceballos L.,University of Cantabria |
And 6 more authors.
PLoS ONE | Year: 2012
CTCF is a ubiquitous epigenetic regulator that has been proposed as a master keeper of chromatin organisation. CTCF-like, or BORIS, is thought to antagonise CTCF and has been found in normal testis, ovary and a large variety of tumour cells. The cellular function of BORIS remains intriguing although it might be involved in developmental reprogramming of gene expression patterns. We here unravel the expression of CTCF and BORIS proteins throughout human epidermis. While CTCF is widely distributed within the nucleus, BORIS is confined to the nucleolus and other euchromatin domains. Nascent RNA experiments in primary keratinocytes revealed that endogenous BORIS is present in active transcription sites. Interestingly, BORIS also localises to interphase centrosomes suggesting a role in the cell cycle. Blocking the cell cycle at S phase or mitosis, or causing DNA damage, produced a striking accumulation of BORIS. Consistently, ectopic expression of wild type or GFP- BORIS provoked a higher rate of S phase cells as well as genomic instability by mitosis failure. Furthermore, down-regulation of endogenous BORIS by specific shRNAs inhibited both RNA transcription and cell cycle progression. The results altogether suggest a role for BORIS in coordinating S phase events with mitosis. © 2012 Rosa-Garrido et al.
Gandarillas A.,Fundacion Marques Of Valdecilla Institute Formacion E Investigacion Marques Of Valdecilla |
Gandarillas A.,French Institute of Health and Medical Research |
Freije A.,Fundacion Marques Of Valdecilla Institute Formacion E Investigacion Marques Of Valdecilla
Experimental Dermatology | Year: 2014
There is likely general consensus within the skin research community that cell cycle control is critical to epidermal homeostasis and disease. The current predominant model proposes that keratinocytes switch off DNA replication and undergo cell cycle and cell growth arrest as they initiate terminal differentiation. However, this model cannot explain key physiological features of the skin, mainly why squamous differentiation prevails over proliferation in benign hyperproliferative disorders. In recent years, we have proposed an alternative model that involves mitotic slippage and endoreplication. This new model is controversial and has encountered resistance within the field. However, looking back at history, the epidermal cell cycle has been a matter of controversy and debate for around 100 years now. The accumulated data are confusing and contradictory. Our present model can explain and reconcile both old and new paradoxical observations. Here, we explain and discuss the endoreplicative cell cycle, the evidence for and against its existence in human epidermis and the important implications for skin homeostasis and disease. We show that regardless of the strengths or weaknesses of the Endoreplication Model, the existing evidence in support of the Cell Cycle Arrest Model is very weak. © 2013 John Wiley & Sons A/S.