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1.  Quantitative and simultaneous translational control of distinct mammalian mRNAs 
Nucleic Acids Research  2013;41(13):e135.
The introduction of multiple genes into cells is increasingly required for understanding and engineering biological systems. Small-molecule–responsive transcriptional regulation has been widely used to control transgene expression. In contrast, methods for specific and simultaneous regulation of multiple genes with a single regulatory protein remain undeveloped. In this report, we describe a method for quantitatively tuning the expression of multiple transgenes with a translational regulatory protein. A protein that binds a specific RNA motif inserted in the 5′-untranslated region (UTR) of an mRNA modulates the translation of that message in mammalian cells. We provide two independent mechanisms by which to rationally fine-tune the output: the efficiency of translation correlates well with the distance between the inserted motif and the 5′ terminus of the mRNA and is further modulated by the tandem insertion of multiple RNA motifs. The combination of these two approaches allowed us to fine-tune the translational efficiency of target mRNAs over a wide dynamic range. Moreover, we controlled the expression of two transgenes simultaneously and specifically by engineering each cis-regulatory 5′-UTR. The approach provides a useful alternative regulatory layer for controlling gene expression in biological research and engineering.
PMCID: PMC3711428  PMID: 23685611
2.  Electroencephalogram abnormalities in panic disorder patients: a study of symptom characteristics and pathology 
Since the 1980s, a high EEG abnormality rate has been reported for patients with panic disorder. However, how the EEG abnormalities of panic disorder patients are related to the clinical features and pathology of these patients has yet to be clarified. In this study we investigated whether or not EEG abnormalities are related to the 13 symptoms in the DSM-IV criteria for a diagnosis of panic attacks.
Subjects were 70 patients diagnosed with panic disorder.
Logistic regression analysis was performed with EEG findings as dependent variables and age, sex and with or without the 13 symptoms as independent variables.
(1)EEG findings for panic disorder patients with EEG abnormalities: Of the 17 patients, 13 had repeated slow waves in the θ-band; the most prevalent EEG abnormality found in this study. Paroxysmal abnormality interpreted as epileptiform was found in only two cases. (2)Nausea or abdominal distress (37.7% vs 82.45%, OR-12.5), derealization or depersonalization (7.5% vs 47.1%, OR = 13.9,) and paresthesias (43.4% vs 64.7%, OR = 7.9,) were extracted by multivariate analysis as factors related to EEG abnormalities.
Of the 70 patients studied, 17 had EEG abnormalities. Among these 17 cases, "repeated slow waves in the θ-band" was the most common abnormality. The factors identified as being related to EEG abnormalities are nausea or abdominal distress, derealization or depersonalization, and paresthesias. The study indicated that physiological predispositions are closely related to panic attacks.
PMCID: PMC2940923  PMID: 20731860
3.  Stress and psychological factors before a migraine attack: A time-based analysis 
The objective of this study is to examine the stress and mood changes of Japanese subjects over the 1–3 days before a migraine headache.
The study participants were 16 patients with migraines who consented to participate in this study. Each subject kept a headache diary four times a day for two weeks. They evaluated the number of stressful events, daily hassles, domestic and non-domestic stress, anxiety, depressive tendency and irritability by visual analog scales. The days were classified into migraine days, pre-migraine days, buffer days and control days based on the intensity of the headaches and accompanying symptoms, and a comparative study was conducted for each factor on the migraine days, pre-migraine days and control days.
The stressful event value of pre-migraine days showed no significant difference compared to other days. The daily hassle value of pre-migraine days was the highest and was significantly higher than that of buffer days. In non-domestic stress, values on migraine days were significantly higher than on other days, and there was no significant difference between pre-migraine days and buffer days or between pre-migraine days and control days. There was no significant difference in the values of domestic stress between the categories. In non-domestic stress, values on migraine days were significantly higher than other days, and there was no significant difference between pre-migraine days and buffer days or between pre-migraine days and control days.
There was little difference in sleep quality on migraine and pre-migraine days, but other psychological factors were higher on migraine days than on pre-migraine days.
Psychosocial stress preceding the onset of migraines by several days was suggested to play an important role in the occurrence of migraines. However, stress 2–3 days before a migraine attack was not so high as it has been reported to be in the United States and Europe. There was no significant difference in the values of psychological factors between pre-migraine days and other days.
PMCID: PMC2556692  PMID: 18799013
4.  Fluorescent Amplified Fragment Length Polymorphism and Repetitive Extragenic Palindrome-PCR Fingerprinting Reveal Host-Specific Genetic Diversity of Vibrio halioticoli-Like Strains Isolated from the Gut of Japanese Abalone 
When analyzed by fluorescent amplified fragment length polymorphism and repetitive extragenic palindrome-PCR fingerprinting, a total of 47 Vibrio halioticoli strains isolated from four Japanese abalone species and one turban shell species formed three clusters that roughly reflect the different species of host abalone from which they were isolated. The V. halioticoli isolates from turban shells were distributed evenly among the clusters. Representative isolates from two clusters were deemed separate species or subspecies by DNA-DNA hybridization.
PMCID: PMC124011  PMID: 12147522
5.  Feedback Control of Protein Expression in Mammalian Cells by Tunable Synthetic Translational Inhibition 
ACS Synthetic Biology  2011;1(3):83-88.
Feedback regulation plays a crucial role in dynamic gene expression in nature, but synthetic translational feedback systems have yet to be demonstrated. Here we use an RNA/protein interaction-based synthetic translational switch to create a feedback system that tightly controls the expression of proteins of interest in mammalian cells. Feedback is mediated by modified ribosomal L7Ae proteins, which bind a set of RNA motifs with a range of affinities. We designed these motifs into L7Ae-encoding mRNA. Newly translated L7Ae binds its own mRNA, inhibiting further translation. This inhibition tightly feedback-regulates the concentration of L7Ae and any fusion partner of interest. A mathematical model predicts system behavior as a function of RNA/protein affinity. We further demonstrate that the L7Ae protein can simultaneously and tunably regulate the expression of multiple proteins of interest by binding RNA control motifs built into each mRNA, allowing control over the coordinated expression of protein networks.
PMCID: PMC4165468  PMID: 23651072
synthetic biology; feedback; translational regulation; RNA; L7Ae; RNA−protein interactions
6.  A versatile cis-acting inverter module for synthetic translational switches 
Nature Communications  2013;4:2393.
Artificial genetic switches have been designed and tuned individually in living cells. A method to directly invert an existing OFF switch to an ON switch should be highly convenient to construct complex circuits from well-characterized modules, but developing such a technique has remained a challenge. Here we present a cis-acting RNA module to invert the function of a synthetic translational OFF switch to an ON switch in mammalian cells. This inversion maintains the property of the parental switch in response to a particular input signal. In addition, we demonstrate simultaneous and specific expression control of both the OFF and ON switches. The module fits the criteria of universality and expands the versatility of mRNA-based information processing systems developed for artificially controlling mammalian cellular behaviour.
Artificial genetic circuits have been designed to enable precise control of cellular behaviour and phenotypes. Saito and colleagues present a new RNA module that can invert the function of a translational OFF to an ON switch and demonstrate its utility in mammalian cells.
PMCID: PMC3778853  PMID: 23999119
7.  Synthetic human cell fate regulation by protein-driven RNA switches 
Nature Communications  2011;2:160-.
Understanding how to control cell fate is crucial in biology, medical science and engineering. In this study, we introduce a method that uses an intracellular protein as a trigger for regulating human cell fate. The ON/OFF translational switches, composed of an intracellular protein L7Ae and its binding RNA motif, regulate the expression of a desired target protein and control two distinct apoptosis pathways in target human cells. Combined use of the switches demonstrates that a specific protein can simultaneously repress and activate the translation of two different mRNAs: one protein achieves both up- and downregulation of two different proteins/pathways. A genome-encoded protein fused to L7Ae controlled apoptosis in both directions (death or survival) depending on its cellular expression. The method has potential for curing cellular defects or improving the intracellular production of useful molecules by bypassing or rewiring intrinsic signal networks.
The control of cell fate and apoptosis is a continuing challenge in synthetic biology. In this study, systems are developed in which an intracellularly expressed genome-encoded protein simultaneously achieves up- and downregulation of two distinct apoptosis pathways.
PMCID: PMC3105309  PMID: 21245841

Results 1-7 (7)