Transgenic mice overexpressing the nonmuscle myosin heavy chain-IIB (NMHC-IIB) specifically in cardiac myocytes or more ubiquitously are being established and will be crossed to the NMHC-IIB deficient mice to test if adding the NMHC-IIB back to the cardiac myocytes is sufficient to prevent the NMHC-IIB deficient mice from developing the structural cardiac defects. The results will also be useful to evaluate effects of the NMHC-IIB on the development of the nonmuscle cells, such as neuronal cells which are enriched in NMHC-IIB. The latter has been plagued by the fact that NMHC-IIB deficient mice died shortly before or after birth. Currently, the NMHC-IIB plasmid has been constructed and the transgenic mice are being produced with our collaborators. The green fluorescent protein (GFP) fused to human NMHC-IIB cDNA has also been used to trace the localization of the NMHC-IIB in transfected living cell lines. The GFP fused to a N-terminal fragment containing the head and neck domain dispersed in the cytoplasm and nucleus of the transfected COS-7 and RBL cell lines, as was also seen with GFP control construct. However, the GFP fused to the tail domain or the complete sequence of human NMHC-IIB cDNA was localized in these cells, close to the plasma membrane, or to perinuclear regions. Further dissection of the tail region showed that a small domain of the NMHC-IIB tail comprised of about 300 amino acids is necessary and sufficient for the localization of the human NMHC-IIB.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Intramural Research (Z01)
Project #
1Z01HL004216-07
Application #
6162726
Study Section
Special Emphasis Panel (LMC)
Project Start
Project End
Budget Start
Budget End
Support Year
7
Fiscal Year
1997
Total Cost
Indirect Cost
Name
National Heart, Lung, and Blood Institute
Department
Type
DUNS #
City
State
Country
United States
Zip Code