Heather J. Montgomery

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Le provided valuable research assistance. The opinions expressed in the paper are those of the authors and not of the institutions they are affiliated with. The views expressed in this paper are those of the author(s) and do not necessarily reflect the views or policies of the Asian Development Bank. Foreword The ERD Working Paper Series is a forum for(More)
Contributions to this research made by a member of The Financial Access Initiative. Abstract ―Best practice‖ in microfinance holds that interest rates should be set at profit-making levels, based on the belief that even poor customers favor access to finance over low fees. Despite this core belief, little direct evidence exists on the price elasticity of(More)
Four optically pure conformationally restricted L-arginine analogues syn- 1 and anti- 2 trans-3,4-cyclopropyl L-arginine, and syn- 3 and anti-trans-3,4-cyclopropyl N-(1-iminoethyl) L-ornithine 4 were synthesized. These compounds were tested as potential inhibitors against the three isoforms of nitric oxide synthase (NOS). Compound 1 was determined to be a(More)
The interactions of neuronal nitric-oxide synthase (nNOS) with calmodulin (CaM) and mutant forms of CaM, including CaM-troponin C chimeras, have been previously reported, but there has been no comparable investigation of CaM interactions with the other constitutively expressed NOS (cNOS), endothelial NOS (eNOS), or the inducible isoform (iNOS). The present(More)
Neuronal nitric-oxide synthase (NOS) and endothelial NOS are constitutive NOS isoforms that are activated by binding calmodulin in response to elevated intracellular calcium. In contrast, the inducible NOS isoform binds calmodulin at low basal levels of calcium in resting cells. Primary sequence comparisons show that each constitutive NOS isozyme contains a(More)
Nitric oxide (NO) plays a critical role in a number of physiological processes and is produced in mammalian cells by nitric oxide synthase (NOS) isozymes. Because of the diverse functions of NO, pharmaceutical interventions which seek to abrogate adverse effects of excess NOS activity must not interfere with the normal regulation of NO levels in the body. A(More)
Several calmodulin (CaM) mutants were engineered in an effort to identify the functional implications of the oxidation of individual methionines in CaM on the activity of the constitutive isoforms of nitric oxide synthase (NOS). Site-directed mutagenesis was used to substitute the majority of methionines with leucines. Substitution of all nine methionine(More)
Transgene variegation is caused by epigenetic switching between expressing and silent states. gamma-retrovirus vectors can be variegated in stem cells, but the dynamics of epigenetic remodeling during transgene variegation are unknown. Here, we measured variegated enhanced green fluorescent protein gamma-retrovirus expression over 4 days in individual(More)
Nitric oxide synthases (NOSs) are composed of a flavin-containing reductase domain and a heme-containing oxygenase domain. Each NOS enzyme also contains a calmodulin (CaM) binding domain and requires bound calmodulin for enzymatic activity. The CaM binding properties of the different NOS isozymes differ in the need for free calcium ions (Ca2+). We(More)
The three mammalian nitric-oxide synthases produce NO from arginine in a reaction requiring 3 electrons per NO, which are supplied to the catalytic center from NADPH through reductase domains incorporating FAD and FMN cofactors. The isoforms share a common reaction mechanism and requirements for reducing equivalents but differ in regulation; the endothelial(More)