Transglutaminase action and activation in the skin

Lead Research Organisation: University of Southampton
Department Name: School of Biological Sciences

Abstract

The correct structure of the skin is essential for life; we wish to understand how its highly specialised barrier develops.

The skin has to withstand trauma and prevent excessive water movement both inward and outward. For this it has developed the cornified envelope, a strengthening matrix of interlinked proteins on the outer epidermal layers with a surrounding water-resistant lipid coat. Changes in either the matrix or lipid may result in defects which can be life threatening.

There are seven members of the transglutaminase enzyme family in the skin. Some are recognized as crucial in developing the cornified envelope, and their altered expression plays a role in a variety of debilitating diseases. However the precise roles of other family members are unknown and it is this we are studying.

Our work studies the importance the transglutaminases by experimentally changing their expression levels in the skin of mice to discover if their misregulation is related with disease. In later studies we will follow the roles of these enzymes in the response of the skin to challenges such as to infection or during healing. Our goal is to understand why the skin has developed such a complex family of enzymes and by understanding their functions provide the basis for the design of novel treatments for human skin diseases.

Technical Summary

Transglutaminases catalyse the introduction of stabilising crosslinks between a variety of epidermal proteins and are essential for cornified envelope development. Of the six epidermal isoforms, some exhibit unique and crucial roles. Thus, TGk mutations result in a severe ichthiosis. However, the in vivo significance of other skin transglutaminases is less well understood. We have deleted TGM3 encoding TGe, the main epidermal enzyme, while this generates a hair follicle phenotype little or no alteration occurs in interfollicular skin, suggesting the enzyme is compensated for here. We will study the roles of other transglutaminases in the epidermis, in particular the novel TGe-like enzyme, TGy. As misregulation of activation of these enzymes has been suggested to induce pathology, the effects of TGe over-activity in the skin will also be addressed. A qualitative and quantitative comparison of the crosslinked substrates in these mouse models will be made to define their roles in development and disease.
 
Description BBSRC PhD Studentship
Amount £100,000 (GBP)
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 10/2008 
End 09/2012
 
Description EC
Amount £160,000 (GBP)
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 11/2011 
End 10/2015
 
Description Project Grant
Amount £260,000 (GBP)
Organisation Sichuan University 
Sector Academic/University
Country China
Start 01/2009 
End 01/2011
 
Description University of Southampton, Kerkut Trust, PhD Studentship
Amount £100,000 (GBP)
Organisation The Gerald Kerkut Charitable Trust 
Sector Charity/Non Profit
Country United Kingdom
Start 10/2010 
End 10/2014
 
Description University of Southampton-primer funding
Amount £10,000 (GBP)
Organisation University of Southampton 
Sector Academic/University
Country United Kingdom
Start 01/2011 
End 12/2012
 
Title TGM2 epidermal over-expressing mouse 
Description Transgenic mouse 
Type Of Material Model of mechanisms or symptoms - mammalian in vivo 
Provided To Others? No  
Impact Model of impared wound healing 
 
Title TGM3 -/- 
Description Mutant animal 
Type Of Material Model of mechanisms or symptoms - mammalian in vivo 
Year Produced 2008 
Provided To Others? Yes  
Impact Manuscript submitted for publication, describing roles of proteases in ichthiosis. PMID: 20495178 
URL http://europepmc.org/abstract/MED/20495178
 
Description Analysis of dermal matrix 
Organisation University of Münster
Country Germany 
Sector Academic/University 
PI Contribution Analysis of (collaborators) transgenic mice by CT scans, production of recombinant protiens and knockout mice
Collaborator Contribution Introduced to novel methods for analysis of ECM and endothelial development
Impact Submitted manuscript.
Start Year 2006
 
Description Epidermal Development 
Organisation University of Cologne
Country Germany 
Sector Academic/University 
PI Contribution Recombinant Proteins, Transgenic animals,
Collaborator Contribution Access to novel conditional knockout mice, training in specific methods
Impact Manuscripts accepted Pub med IDs PMID: 19766719 PMID: 18356808 PMID: 17389689 PMID: 17008882
 
Description Study on activation on transglutaminases in skin. 
Organisation Radboud University Nijmegen
Department Radboud Institute for Molecular Life Sciences (RIMLS)
Country Netherlands 
Sector Academic/University 
PI Contribution Produced and purified recombinant enzymes, produced a transgenic mouse
Collaborator Contribution Manuscript for publication, access to novel mouse models of ichthyosisProduction and testing of ELISA assays, access to patient sera bank
Impact Manuscript submitted for publication upon role of transglutaminases in ichthyosis. PMID: 20495178 PMID: 16987503
Start Year 2007
 
Description Study on activation on transglutaminases in skin. 
Organisation Semmelweiss University
Department Department of Dermatology, Venereology and Dermatooncology
Country Hungary 
Sector Academic/University 
PI Contribution Produced and purified recombinant enzymes, produced a transgenic mouse
Collaborator Contribution Manuscript for publication, access to novel mouse models of ichthyosisProduction and testing of ELISA assays, access to patient sera bank
Impact Manuscript submitted for publication upon role of transglutaminases in ichthyosis. PMID: 20495178 PMID: 16987503
Start Year 2007
 
Description College Debate plus Question and Answers 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact Well attended talk with aim of starting school led science projects.

Requests for lab visits-aim of initaiting a mentoring scheme between college and Faculty
Year(s) Of Engagement Activity 2011
 
Description School Debate- Taunton 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Lecture and discussion on use of stem cells -

Return visit from school pupils to the University, applications to study at Southampton University from group
Request for annual lecture
Year(s) Of Engagement Activity 2010
 
Description School visit- Fareham (Local science debating society- students/ parents/ staff) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Debated with students uses of transgenic animals (invited back to talk about stem cells)

Contacts with regional community, increased number of requests for summer lab placements,
Year(s) Of Engagement Activity 2007,2008