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A new species of Bembidion Latrielle 1802 from the Ozarks, with a review of the North American species of subgenus Trichoplataphus Netolitzky 1914 (Coleoptera, Carabidae, Bembidiini)
A new species of Bembidion (Trichoplataphus Netolitzky) from the Ozark Plateau of Missouri and Arkansas is described (Bembidion ozarkense Maddison and Hildebrandt). It is distinguishable from the closely related species, Bembidion rolandi Fall, by characteristics of the male genitalia, and sequences of the genes cytochrome oxidase I and 28S ribosomal DNA. A brief review of the North American species of Trichoplataphus is presented, including a key to species.KEYWORDS: COI, Systematics, Bembidiini, Trechinae, Bembidion, 28S rDNA, Taxonom
Recent insights into the interactions between the baroreflex and the kidneys in hypertension
What can the surgeon expect from endoscopic ultrasound for patients with cancer of the rectum?
A Stable Human-Cell System Overexpressing Cystic Fibrosis Transmembrane Conductance Regulator Recombinant Protein at the Cell Surface
Recent human clinical trials results demonstrated successful treatment for certain genetic forms of cystic fibrosis (CF). To extend treatment opportunities to those afflicted with other genetic forms of CF disease, structural and biophysical characterization of CF transmembrane conductance regulator (CFTR) is urgently needed. In this study, CFTR was modified with various tags, including a His(10) purification tag, the SUMOstar (SUMO*) domain, an extracellular FLAG epitope, or an enhanced green fluorescent protein (EGFP), each alone or in various combinations. Expressed in HEK293 cells, recombinant CFTR proteins underwent complex glycosylation, compartmentalized with the plasma membrane, and exhibited regulated chloride-channel activity with only modest alterations in channel conductance and gating kinetics. Surface CFTR expression level was enhanced by the presence of SUMO* on the N-terminus. Quantitative mass-spectrometric analysis indicated approximately 10% of the total recombinant CFTR (SUMO*-CFTR(FLAG)-EGFP) localized to the plasma membrane. Trial purification using dodecylmaltoside for membrane protein extraction reproducibly recovered 178 ± 56 μg SUMO*-CFTR(FLAG)-EGFP per billion cells at 80% purity. Fluorescence size-exclusion chromatography indicated purified CFTR was monodisperse. These findings demonstrate a stable mammalian cell expression system capable of producing human CFTR of sufficient quality and quantity to augment futrure CF drug discovery efforts, including biophysical and structural studies