Abstract. The A TP2 gene of Saccharomyces cerevisiae codes for the cytoplasmically synthesized 13-subunit protein of the mitochondrial F1-ATPase. To define the amino acid sequence determinants necessary for the in vivo targeting and import of this protein into mitochondria, we have constructed gene fusions between the A TP2 gene and either the Escherichia coli lacZ gene or the S. cerevisiae SUC2 gene (which codes for invertase). The A TP2-1acZ and A TP2-SUC2 gene fusions code for hybrid proteins that are efficiently targeted to yeast mitochondria in vivo. The mitochondrially associated hybrid proteins fractionate with the inner mitochondrial membrane and are resistant to proteinase digestion in the isolated organelle. Results obtained with the gene fusions and with targeting-defective A TP2 deletion mutants provide evidence that the amino-terminal 27 amino acids of the 13Lsubunit protein precursor are sufficient to direct both specific sorting of this protein to yeast mitochondria and its import into the organelle. Also, we have observed that certain of the mitochondrially associated Atp2-LacZ and Atp2-Suc2 hybrid proteins confer a novel respiration-defective phenotype to yeast cells.

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Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp he number of patients with severe angina pectoris without indications for coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) is rapidly increasing worldwide and their prognosis still remains poor. 1,2 Thus, it is crucial to develop new therapeutic strategies for these patients. We have previously demonstrated that extracorporeal cardiac shock wave (SW) therapy with low-energy SW (≈10% of the energy density used for urolithiasis) ameliorates myocardial ischemia and dysfunction in a porcine model of chronic myocardial ischemia in vivo. 3, 4 We subsequently demonstrated in an open trial that our SW therapy effectively improved chest pain symptoms and exercise tolerance without any adverse effects in 9 patients with severe angina pectoris. 3,5 In the present study, to further confirm the effectiveness and safety of our SW therapy, we performed a double-blind placebo-controlled trial in patients with severe angina pectoris. MethodsWe enrolled 8 consecutive patients with severe angina pectoris who already had undergone CABG or PCI, but who no longer had further indications for these therapies even though they still suffered from stable effort angina under intensive medication (M/F, 5/3; age, 70±3 years) (Table).The patients were treated with one series of placebo and the SW therapy in a double-blind and cross-over manner with an interval of 3 months. One series of therapy comprised 3 sessions per week. Throughout the study, the patient and the doctor in charge were not informed of the type of therapy. We performed the SW therapy (200 shoots/spot at 0.09 mJ/mm 2 for 40-60 spots per session; Modulith SLC, Storz Medical, Kreuzlingen, Switzerland) as described previously. 3,5 As placebo, the patients underwent the procedure of SW therapy but without irradiation. The patients were followed-up for 3 months after completion of the therapy. We evaluated symptoms using the Canadian Cardiovascular Society (CCS) class score, the patient's requirement for nitroglycerin, 5 exercise tolerance in a 6-min walk, and a cardiopulmonary exercise test, and cardiac function assessed by MRI (Achieva 1.5 T, Philips, Eindhoven, Netherlands). The left ventricular ejection fraction (LVEF) was measured using contiguous short-axis slices obtained by cine MRI; end-diastolic and end-systolic endocardial traces were used to determine end-diastolic and end-systolic left ventricular (LV) volumes, respectively. We also evaluated the number of circulating progenitor cells in peripheral blood by FACS analysis 2 days before the 1 st session and 1 h after the 3 rd session in 7 of the 8 patients Background: Low-energy shock wave (SW) therapy has improved myocardial ischemia in both a porcine model and in patients with severe angina pectoris.

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Background— Erythropoietin (Epo) receptors (EpoRs) are expressed in the heart. We have recently demonstrated that the endogenous Epo-EpoR system plays an important protective role in myocardial ischemia in mice and humans. In the present study, we tested our hypothesis that the endogenous Epo-EpoR system in nonhematopoietic cells also plays a protective role against pressure overload–induced cardiac dysfunction in vivo. Methods and Results— Transgene-rescued EpoR-null mutant mice ( EpoR −/− rescued ) that express EpoR exclusively in the hematopoietic cells were subjected to transverse aortic constriction (TAC). At 1 week after TAC, left ventricular weight and lung weight were significantly increased in EpoR −/− rescued mice compared with wild-type mice, although the fibrotic area was comparably increased after TAC in the 2 genotypes. In the EpoR −/− rescued mice with TAC, left ventricular end-diastolic diameter was significantly increased, left ventricular fractional shortening was significantly decreased, and survival rate was significantly decreased compared with wild-type mice with TAC. Phosphorylation of STAT3 at 5 hours and 1 week after TAC and that of p38 at 5 hours after TAC were significantly increased in wild-type mice but not in EpoR −/− rescued mice. Vascular endothelial growth factor protein expression and capillary density in left ventricular myocardium were significantly decreased in EpoR −/− rescued mice with TAC compared with wild-type mice with TAC. Conclusions— These results suggest that the endogenous Epo-EpoR system in the nonhematopoietic cells plays an important protective role against pressure overload–induced cardiac dysfunction in vivo.