The nuclear envelope protein Nesprin-2 has roles in cell proliferation and differentiation during wound healing

Abstract

Nesprin-2, a type II transmembrane protein of the nuclear envelope, is a component of the LINC complex that connects the nuclear lamina with the actin cytoskeleton. To elucidate its physiological role we studied wound healing in Nesprin-2 Giant deficient mice and found that a loss of the protein affected wound healing particularly at later stages during fibroblast differentiation and keratinocyte proliferation leading to delayed wound closure. We identified altered expression and localization of transcription factors as one of the underlying mechanisms. Furthermore, the actin cytoskeleton which surrounds the nucleus was altered and keratinocyte migration was slowed down and focal adhesion formation enhanced. We also uncovered a new activity of Nesprin-2. When we probed for an interaction of Nesprin-2 Giant with chromatin we observed in ChIP Seq experiments an association of the protein with heterochromatic and centromeric DNA. Through this activity Nesprin-2 can affect the nuclear landscape and gene regulation. Our findings suggest functions for Nesprin-2 at the nuclear envelope (NE) in gene regulation and in regulation of the actin cytoskeleton which impact on wound healing.

Keywords: :

• LINC-complex
• actin cytoskeleton
• c-Fos
• focal adhesion
• keratinocyte
• signaling
• wound healing

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

This work was supported by the Center for Molecular Medicine Cologne (CMMC) and the Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD). We thank Dr Ralf Hallinger and Profs. Carien Niessen and Sabine Eming (Department of Dermatology, University Hospital Cologne) for helpful suggestions, Dr. U. Euteneuer for providing WA3 antibody, and Rolf Müller, Berthold Gaßen and Martina Munck for help throughout the course of the experiments.