Matthew D Smith

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An abridged five-item version of the 15-item International Index of Erectile Function (IIEF) was developed (IIEF-5) to diagnose the presence and severity of erectile dysfunction (ED). The five items selected were based on ability to identify the presence or absence of ED and on adherence to the National Institute of Health's definition of ED. These items(More)
Plastids represent a diverse group of organelles that perform essential metabolic and signaling functions within all plant cells. The differentiation of specific plastid types relies on the import of selective sets of proteins from among the approximately 2500 nucleus-encoded plastid proteins. The Toc159 family of GTPases mediates the initial targeting of(More)
OBJECTIVES To evaluate the erectile function (EF) domain of the International Index of Erectile Function (IIEF) as a diagnostic tool to discriminate between men with and without erectile dysfunction (ED) and to develop a clinically meaningful gradient of severity for ED. METHODS One thousand one hundred fifty-one men (1035 with and 116 without ED) who(More)
ADP plays a critical role in modulating thrombosis and hemostasis. ADP initiates platelet aggregation by simultaneous activation of two G protein-coupled receptors, P2Y1 and P2Y12. Activation of P2Y1 activates phospholipase C and triggers shape change, while P2Y12 couples to Gi to reduce adenylyl cyclase activity. P2Y12 has been shown to be the target of(More)
The members of the Toc159 family of GTPases act as the primary receptors for the import of nucleus-encoded preproteins into plastids. Toc159, the most abundant member of this family in chloroplasts, is required for chloroplast biogenesis (Bauer, J., K. Chen, A. Hiltbunner, E. Wehrli, M. Eugster, D. Schnell, and F. Kessler. 2000. Nature. 403:203-207) and has(More)
Full-length cDNA corresponding to Arabidopsis (Arabidopsis thaliana) gene At2g31690, which has been annotated in GenBank as a putative triacylglycerol (TAG) lipase, was obtained by reverse transcription-polymerase chain reaction using RNA from senescing rosette leaves of Arabidopsis as a template. The cognate protein was found to contain the lipase active(More)
A variety of transcription factors are targets for conjugation to the ubiquitin-like protein Smt3 (also called SUMO). While many such factors exhibit enhanced activity under conditions that favor conjugation, the mechanisms behind this enhancement are largely unknown. We previously showed that the Drosophila melanogaster rel family factor, Dorsal, is a(More)
This unit describes protocols for isolating chloroplasts from pea (Pisum sativum) and Arabidopsis thaliana for the study of nuclear-encoded plastid precursor proteins. Chloroplasts from both preparations are competent for the in vitro import of recombinant preproteins synthesized using in vitro translation systems derived from reticulocyte or wheat germ(More)
The Brn-3a POU family transcription factor has been shown to strongly activate expression of the Bcl-2 proto-oncogene and thereby protect neuronal cells from programmed cell death (apoptosis). This activation of the Bcl-2 promoter by Brn-3a is strongly inhibited by the p53 anti-oncogene protein. This inhibitory effect of p53 on Brn-3a-mediated(More)
The import of nucleus-encoded preproteins into plastids requires the coordinated activities of membrane protein complexes that facilitate the translocation of polypeptides across the envelope double membrane. Tic20 was identified previously as a component of the import machinery of the inner envelope membrane by covalent cross-linking studies with trapped(More)