Comparison between Wild and Hatchery Populations of Korean Pen Shell (Atrina pectinata) Using Microsatellite DNA Markers

Pen shell (Atrina pectinata) is a popular food source with a high commercial value in a number of Asian Pacific areas. The natural A. pectinata population has been declining continuously over the past several decades. Microsatellite DNA markers are a useful DNA-based tool for monitoring the genetic variation of pen shell populations. In this study, 20 polymorphic microsatellite (MS) DNA markers were identified from a partial genomic pen shell DNA library enriched in CA repeats, and used to compare allelic variation between wild and hatchery pen shell populations in Korea. A total of 438 alleles were detected at the 20 MS loci in the two populations. All loci were easily amplified and demonstrated allelic variability, with the number of alleles ranging from 5 to 35 in the wild population and from 5 to 22 in the farmed population. The average observed and expected heterozygosities were 0.69 and 0.82, respectively, in the hatchery samples and 0.69 and 0.83, respectively, in the wild samples. Statistical analysis of fixation index (FST) and analysis of molecular variance (AMOVA) showed minor, but significant, genetic differences between the wild and hatchery populations (FST = 0.0106, CI95% = 0.003–0.017). These microsatellite loci may be valuable for future aquaculture and population genetic studies for developing conservation and management plans. Further studies with additional pen shell samples are needed to conclusively determine the genetic diversity between the wild and hatchery populations

Clinical characteristics of patients with treated epilepsy in Korea: A nationwide epidemiologic study

Objective: Although a number of epidemiologic studies have been conducted on the prevalence and incidence of epilepsy around the world, only a few studies have investigated the clinical characteristics of patients with epilepsy in a population-based sample. The purpose of the present study was to describe the clinical characteristics of treated patients with epilepsy in Korea via a nationwide medical records survey. MethodsThe study population was obtained through a nationwide database registered to the Health Insurance Review and Assessment service. Patients were recruited from clinics and hospitals in each cluster according to region and referral level by random selection from a preallocated sample of patients. All patients were being treated with antiepileptic drug medication with or without a diagnosis code for epilepsy or seizure between January 2009 and December 2009. Among the 6,436 selected patients, 2,150 met the diagnostic criteria for epilepsy and were included in our survey on the clinical characteristics of patients who were with treated epilepsy. ResultsThe proportion of male patients with epilepsy in this study was higher (1,226; 57.0%) than that of female patients. In addition, 10.6% of patients were first diagnosed with epilepsy in 2009, and 53.6% of patients experienced at least one seizure over the course of 2009; 78.1% were classified as having localization-related epilepsy, whereas 7.3% were considered to have generalized epilepsy. Thirty-five percent of patients were thus classified as idiopathic or cryptogenic cases. The most common cause of symptomatic epilepsy was trauma (10.0%), followed by stroke (9.6%), central nervous system (CNS) infection (5.7%), and hippocampal sclerosis (4.9%). SignificanceThis is the first nationwide study of the clinical characteristics of treated epilepsy in Korea using a national database validated by medical records survey. The etiologies of epilepsy and epilepsy syndrome classifications were comparable to those previously reported in other developed countries.OAIID:oai:osos.snu.ac.kr:snu2014-01/102/2014017262/1SEQ:1PERF_CD:SNU2014-01EVAL_ITEM_CD:102USER_ID:2014017262ADJUST_YN:YEMP_ID:A079623DEPT_CD:801CITE_RATE:3.909DEPT_NM:의학과SCOPUS_YN:YCONFIRM:

Structural analysis of Tha4, a twin-arginine translocase protein localized in plant thylakoid membranes

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Functional Characterization of Sequence Motifs in the Transit Peptide of Arabidopsis Small Subunit of Rubisco

The transit peptides of nuclear-encoded chloroplast proteins are necessary and sufficient for targeting and import of proteins into chloroplasts. However, the sequence information encoded by transit peptides is not fully understood. In this study, we investigated sequence motifs in the transit peptide of the small subunit of the Rubisco complex by examining the ability of various mutant transit peptides to target green fluorescent protein reporter proteins to chloroplasts in Arabidopsis (Arabidopsis thaliana) leaf protoplasts. We divided the transit peptide into eight blocks (T1 through T8), each consisting of eight or 10 amino acids, and generated mutants that had alanine (Ala) substitutions or deletions, of one or two T blocks in the transit peptide. In addition, we generated mutants that had the original sequence partially restored in single- or double-T-block Ala (A) substitution mutants. Analysis of chloroplast import of these mutants revealed several interesting observations. Single-T-block mutations did not noticeably affect targeting efficiency, except in T1 and T4 mutations. However, double-T mutants, T2A/T4A, T3A/T6A, T3A/T7A, T4A/T6A, and T4A/T7A, caused a 50% to 100% loss in targeting ability. T3A/T6A and T4A/T6A mutants produced only precursor proteins, whereas T2A/T4A and T4A/T7A mutants produced only a 37-kD protein. Detailed analyses revealed that sequence motifs ML in T1, LKSSA in T3, FP and RK in T4, CMQVW in T6, and KKFET in T7 play important roles in chloroplast targeting. In T1, the hydrophobicity of ML is important for targeting. LKSSA in T3 is functionally equivalent to CMQVW in T6 and KKFET in T7. Furthermore, subcellular fractionation revealed that Ala substitution in T1, T3, and T6 produced soluble precursors, whereas Ala substitution in T4 and T7 produced intermediates that were tightly associated with membranes. These results demonstrate that the transit peptide contains multiple motifs and that some of them act in concert or synergistically