Ubiquitous Gasp1 overexpression in mice leads mainly to a hypermuscular phenotype

BMC Genomics

Research Article

Caroline Brun¹  Katy Heu¹  Olivier Monestier¹  Mélanie Malhouroux¹  Laetitia Magnol¹  Véronique Blanquet¹  Jean-Luc Vilotte²  Bruno Passet² 

[1] INRA, UMR1061 Unité de Génétique Moléculaire Animale, 87060, Limoges, France;Université de Limoges, 87060, Limoges, France;INRA, UMR1313 GABI Génétique Animale et Biologie Intégrative, 78352, Jouy-en-Josas, France;

关键词: Activin;    Pectoralis Major Muscle;    Skeletal Muscle Growth;    Myostatin Inhibition;    Myofiber Size;   

DOI  :  10.1186/1471-2164-13-541

 received in 2011-11-14, accepted in 2012-10-03,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundMyostatin, a member of the TGFβ superfamily, is well known as a potent and specific negative regulator of muscle growth. Targeting the myostatin signalling pathway may offer promising therapeutic strategies for the treatment of muscle-wasting disorders. In the last decade, various myostatin-binding proteins have been identified to be able to inhibit myostatin activity. One of these is GASP1 (Growth and Differentiation Factor-Associated Serum Protein-1), a protein containing a follistatin domain as well as multiple domains associated with protease inhibitors. Despite in vitro data, remarkably little is known about in vivo functions of Gasp1. To further address the role of GASP1 during mouse development and in adulthood, we generated a gain-of-function transgenic mouse model that overexpresses Gasp1 under transcriptional control of the human cytomegalovirus immediate-early promoter/enhancer.ResultsOverexpression of Gasp1 led to an increase in muscle mass observed not before day 15 of postnatal life. The surGasp1 transgenic mice did not display any other gross abnormality. Histological and morphometric analysis of surGasp1 rectus femoris muscles revealed an increase in myofiber size without a corresponding increase in myofiber number. Fiber-type distribution was unaltered. Interestingly, we do not detect a change in total fat mass and lean mass. These results differ from those for myostatin knockout mice, transgenic mice overexpressing the myostatin propeptide or follistatin which exhibit both muscle hypertrophy and hyperplasia, and show minimal fat deposition.ConclusionsAltogether, our data give new insight into the in vivo functions of Gasp1. As an extracellular regulatory factor in the myostatin signalling pathway, additional studies on GASP1 and its homolog GASP2 are required to elucidate the crosstalk between the different intrinsic inhibitors of the myostatin.

【 授权许可】

Unknown   
© Monestier et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.