Postnatal myosin heavy chain isoforms in prenatal porcine skeletal muscles: insights into temporal regulation.
Our knowledge of the temporal expression of postnatal (adult) fast myosin heavy chain (MyHC) isoforms (2a, 2x, and 2b) in prenatal muscles is limited. Using the pig as a target species and large-animal model, we report on the qualitative and quantitative expression of the major post- and prenatal MyHC isoforms during gestation, as determined by TaqMan real-time PCR and immunohistochemistry. We found that postnatal fast MyHC mRNAs and proteins were expressed much earlier in the pig (gestation day 35) than was previously reported in small mammals. There was a high degree of coexpression and colocalisation of pre- and postnatal MyHC mRNAs and proteins in prenatal muscles. During a period of prenatal muscle growth (gestation days 35-77), relative expression of MyHC isoforms (embryonic > 2a > 2x > 2b) correlated with the gene order in the skeletal MyHC cluster, which suggests the possible presence of cis-acting elements on the same side as the MyHC embryonic gene associated with temporal regulation.
da Costa
Nuno
N
Veterinary Molecular Medicine Laboratory, Institute of Comparative Medicine, University of Glasgow Veterinary School, Glasgow, Scotland.
McGillivray
Christine
C
Chang
Kin-Chow
KC
D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D005333:Fetus; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D005809:Genes, Regulator / Q000235:genetics; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D018995:Myosin Heavy Chains / Q000235:genetics* / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D034421:Sus scrofa; D013997:Time Factors
D020033:Protein Isoforms; D012333:RNA, Messenger; D018995:Myosin Heavy Chains