Sparing dystrophic muscle
Research at NMDRC Skeletal muscle Development and Hypertrophy Dystrophic Pathology Skeletal Muscle Regeneration Stem cells and Cell Transplantation Identification and manipulation of factors which play a role in hypertrophy Callipyge sheep Myostatin Growth Factors Delivery of factors to dystrophic skeletal muscle to ameliorate the progression of dystrophy Understanding and enhancing skeletal muscle regeneration Use of precursor cells as a gene correction methodology
The Central Dogma 3mG mrna Protein DNA
H3 H4 H2B H4 H2A H3 DNA Packaging
Reading the DNA code RNA DNA
A Simple Cell 3mG RNA Protein
Muscle Development and Regeneration Myoblast Myotube Fusion
FSHD
FSHD Majority of FSH cases linked to D4Z4 repeat on chromosome 4 General population 11-100 repeats FSH 1 to 10 Small proportion (<5%) phenotypic
FSHD No mutation in a specific gene Must be other mechanisms that result in loss of control
Epigenetic mechanism Improper packaging of DNA leaves it open Altered production of genes H3 H4 H2B H4 H2A H3
Loss of control FRG1 = muscular dystrophy FRG2 or ANT1 = no effect
Experimental Approaches to Treatment
Cell transplantation from non-affected muscles Drugs that change methylation status
Principle of Cell Transplantation NORMAL MUSCLE makes dystrophin DYSTROPHIC MUSCLE lacks dystrophin Stuart Hodgetts Tracey Pullen-Lee
Principle of Myoblast Transfer Therapy Cultured normal myoblasts injected into dystrophic muscle MOSAIC MUSCLE FIBRE
Myotonic Dystrophy Unstable expansion of CTG repeats Accumulation of RNA in nucleus (cellular toxicity) Toxic gain of function
A Simple Cell 3mG RNA Protein
Muscle Development and Regeneration Myoblast Myotube Fusion
Therapeutic strategies Manipulation of RNA degradation pathways to clear accumulated RNA Flavonoids and DHEA-S alleviate toxic effects in tissue culture
Limb Girdle Type2A Calpain
LGMD 2A Calpain 3 Affected protein is an enzyme not a structural element? Reduced capacity for normal protein turnover Assumes a role in generalized protein clearance
Other roles for calpain 3 Cytoskeleton rearrangements Sarcomere formation and remodelling Cell death
Increasing muscle regeneration/growth Callipyge and myostatin
Research at NMDRC Skeletal muscle Development and Hypertrophy Dystrophic Pathology Skeletal Muscle Regeneration Stem cells and Cell Transplantation Identification and manipulation of factors which play a role in hypertrophy Callipyge sheep Myostatin Growth Factors Delivery of factors to dystrophic skeletal muscle to ameliorate the progression of dystrophy Understanding and enhancing skeletal muscle regeneration Use of precursor cells as a gene correction methodology
Callipyge 1983 Solid Gold Hypertrophy of hindquarters SNP on Chromosome 18 (CLPG) beautiful buttocks Superior feed efficiency Polar overdominance NOELLE E. COCKETT, PhD Professor Utah State University ADVS Department 4815 Old Main Hill Logan UT 84322-4815 tel. (435) 797-2215 fax. (435) 797-3904 e-mail: fanoelle@cc.usu.edu
Solid Gold The Founder of Callipyge
Callipyge (CN) Normal (NN) Unaffected Affected
Target HDAC9
Effect of Valproate (VPA) A B C Control 5mM VPA 10mM VPA
Texel The Texel Breed is famed for its exceptional carcass qualities, which has resulted in the Breed becoming the dominant terminal sire used in the UK. QTL recently identified in region of myostatin gene. J Animal Sci. Nov 2004.
Myostatin
Vaccination against Myostatin Negative regulator of muscle cell growth Thus Need to remove (similar to MYO29)
Research at NMDRC Skeletal muscle Development and Hypertrophy Dystrophic Pathology Skeletal Muscle Regeneration Stem cells and Cell Transplantation Identification and manipulation of factors which play a role in hypertrophy Callipyge sheep Myostatin Growth Factors Delivery of factors to dystrophic skeletal muscle to ameliorate the progression of dystrophy Understanding and enhancing skeletal muscle regeneration Use of precursor cells as a gene correction methodology