The positional cloning and expression studies of the IMMUTANS variegation locus of Arabidopsis thaliana

immutans (im), a nuclear gene induced variegation mutation of Arabidopsis, causes green- and white-sectored leaves and is recessive. The green sectors contain cells with normal chloroplasts, whereas the white sectors are heteroplastidic and contain cells with abnormal, pigment-deficient plastids as well as some normal chloroplasts. The white sectors accumulate the carotenoid precursor phytoene. We have cloned IM by chromosome walking and found that the gene encodes a 40.5-kD chloroplast thylakoid membrane protein with sequence motifs characteristic of alternative oxidase, a mitochondrial protein that functions as a terminal oxidase in the respiratory chains of all plants. IM protein functions as a component of a redox. chain responsible for phytoene desaturation. Our research on IM expression at the transcriptional level reveals that IM is expressed ubiquitously and it suggests that IM may play roles in different kinds of plastids including chloroplasts, leucoplasts, chromoplasts and etioplasts. In addition to carotenoid biosynthesis, IM may play a general role in desaturation reactions in plastids

Systematic identification of gene families for use as markers for phylogenetic and phylogeny- driven ecological studies of bacteria and archaea and their major subgroups

With the astonishing rate that the genomic and metagenomic sequence data sets are accumulating, there are many reasons to constrain the data analyses. One approach to such constrained analyses is to focus on select subsets of gene families that are particularly well suited for the tasks at hand. Such gene families have generally been referred to as marker genes. We are particularly interested in identifying and using such marker genes for phylogenetic and phylogeny-driven ecological studies of microbes and their communities. We therefore refer to these as PhyEco (for phylogenetic and phylogenetic ecology) markers. The dual use of these PhyEco markers means that we needed to develop and apply a set of somewhat novel criteria for identification of the best candidates for such markers. The criteria we focused on included universality across the taxa of interest, ability to be used to produce robust phylogenetic trees that reflect as much as possible the evolution of the species from which the genes come, and low variation in copy number across taxa. We describe here an automated protocol for identifying potential PhyEco markers from a set of complete genome sequences. The protocol combines rapid searching, clustering and phylogenetic tree building algorithms to generate protein families that meet the criteria listed above. We report here the identification of PhyEco markers for different taxonomic levels including 40 for all bacteria and archaea, 114 for all bacteria, and much more for some of the individual phyla of bacteria. This new list of PhyEco markers should allow much more detailed automated phylogenetic and phylogenetic ecology analyses of these groups than possible previously.Comment: 24 pages, 3 figure

Gliclazide impurity F: N-[(perhydro­cyclo­penta­[c]pyrrol-2-yl)amino­carbon­yl]-o-toluene­sulfonamide

The title compound, C15H21N3O3S, is known to be an impurity of gliclazide [systematic name: N-(hexa­hydro-1H-cyclopenta[c]pyrrol-2-ylcarbamo­yl)-4-methyl­benzene­sulfonamide], a sul­fonyl­urea anti­diabetic drug. Gliclazide has a p-tolyl group substituting the sulfonamide functionality, while the title mol­ecule contains an o-tolyl group. Both five-membered fused rings adopt envelope conformations. In the crystal, N—H⋯O hydrogen bonds are formed between HN(C=O)NH groups, building centrosymmetric dimers. These dimers are further linked through N—H⋯O(sulfon­yl) contacts, forming chains in [100]

Activation Of α7 Nicotinic Acetylcholine Receptors Prevents Monosodium Iodoacetate-Induced Osteoarthritis In Rats

Background/Aims: Although some evidence suggests that the prevalence of osteoarthritis (OA) is lower in smokers compared to nonsmokers, the mechanisms of nicotine-induced protection remain unclear. Stimulation of the α7 nicotinic acetylcholine receptor (α7-nAChR) appears to be a critical mechanism underlying the anti-inflammatory potential of cholinergic agonists in immune cells. The inhibition of secreted inflammatory molecules and the subsequent inflammatory processes have been proposed as a novel strategy for the treatment of OA. The objective of the present study was to determine whether nicotine-induced protection in a monosodium iodoacetate (MIA) rat model of OA occurs via α7-nAChR-mediated inhibition of chondrocytes. Methods: Both in vivo (MIA) and in vitro (MIA; Interleukin-1β, IL-1β) models of OA were used to investigate the roles and the possible mechanisms whereby α7-nAChRs protect against knee joint degradation. Multiple experimental approaches, including macroscopic, histological analysis, chondrocyte cell cultures, confocal microscopy, and western blotting, were employed to elucidate the mechanisms of α7-nAChR-mediated protection. Results: Systemic administration of nicotine alleviated MIA-induced joint degradation. The protective effects of nicotine were abolished by administration of the α7-nAChR-selective antagonist methyllycaconitine (MLA). In primary cultured rat chondrocytes, pretreatment with nicotine suppressed both p38, extracellular regulated kinase (Erk) 1/2 and c-Jun-N-terminal kinase (JNK) mitogen-activated protein kinases (MAPK) phosphorylation and phosphorylated nuclear factor-kappa B (NF-κB) p65 activation induced by MIA- or IL-1β, and these effects were also reversed by MLA. Conclusion: Taken together, our results suggest that activation α7-nAChRs is an important mechanism underlying the protective effects of nicotine

Effect of metabotropic glutamate receptor 3 genotype on N-acetylaspartate levels and neurocognition in non-smoking, active alcoholics

BACKGROUND: We studied the effects of single nucleotide polymorphisms (SNPs) in the metabotropic glutamate receptor 3 (GRM3) gene on brain N-acetylaspartate (NAA) concentrations and executive function (EF) skills in non-smoking, active alcoholics, and evaluated associations between these variables. METHODS: SNPs (rs6465084, rs1468412, and rs2299225) in GRM3 were genotyped in 49 male, non-smoking, alcohol-dependent patients and 45 healthy control subjects using ligase detection reactions. NAA/creatine (Cr) ratios in left prefrontal gray matter (GM) and white matter (WM), left parietal GM, left parietal WM, and cerebellar vermis regions were measured by Proton (1) H Magnetic resonance spectroscopy (MRS). EF was measured by the Wisconsin Card Sorting Test (WCST). RESULTS: Compared to controls, alcoholics had lower NAA/Cr ratios in prefrontal GM and WM regions and performed more poorly on all EF tests (P < 0.001). Alcoholics with the A/A genotype for SNP rs6465084 had lower NAA/Cr ratios in prefrontal GM and WM regions and had poorer EF skills than alcoholics who were G-carriers for this SNP (P < 0.01). Non-alcoholics with the A/A genotype for rs6465084 also had lower NAA/Cr levels in prefrontal GM and made more random errors in the WCST than G-carriers (P < 0.01). The A/A genotype group for SNP rs6465084 was significantly different from the G carriers for the variables of NAA/Cr ratios and WCST scores in both alcoholics and controls (P < 0.05). Alcoholics who were T-carriers for rs1468412 had lower NAA/Cr ratios in prefrontal GM and showed poorer EF skills (P < 0.05). No effects of rs2299225 genotype on NAA/Cr or executive skills were observed. NAA/Cr in left prefrontal regions correlated with certain parameters of EF testing in both alcoholics and controls (P < 0.05), but the significance of this correlation among alcoholics disappeared after adjustment for the effects of genotype. CONCLUSIONS: Our results provide evidence that glutamate system dysfunction may play a role in the prefrontal functional abnormalities seen in alcohol dependence. It is possible that certain GRM3 SNP genotypes (the A/A genotype of rs6465084 and the T allele of rs1468412) may further lower NAA/Cr levels and EF skills in addition to the effect of alcohol

Stalking the Fourth Domain in Metagenomic Data: Searching for, Discovering, and Interpreting Novel, Deep Branches in Marker Gene Phylogenetic Trees

BACKGROUND: Most of our knowledge about the ancient evolutionary history of organisms has been derived from data associated with specific known organisms (i.e., organisms that we can study directly such as plants, metazoans, and culturable microbes). Recently, however, a new source of data for such studies has arrived: DNA sequence data generated directly from environmental samples. Such metagenomic data has enormous potential in a variety of areas including, as we argue here, in studies of very early events in the evolution of gene families and of species. METHODOLOGY/PRINCIPAL FINDINGS: We designed and implemented new methods for analyzing metagenomic data and used them to search the Global Ocean Sampling (GOS) expedition data set for novel lineages in three gene families commonly used in phylogenetic studies of known and unknown organisms: small subunit rRNA and the recA and rpoB superfamilies. Though the methods available could not accurately identify very deeply branched ss-rRNAs (largely due to difficulties in making robust sequence alignments for novel rRNA fragments), our analysis revealed the existence of multiple novel branches in the recA and rpoB gene families. Analysis of available sequence data likely from the same genomes as these novel recA and rpoB homologs was then used to further characterize the possible organismal source of the novel sequences. CONCLUSIONS/SIGNIFICANCE: Of the novel recA and rpoB homologs identified in the metagenomic data, some likely come from uncharacterized viruses while others may represent ancient paralogs not yet seen in any cultured organism. A third possibility is that some come from novel cellular lineages that are only distantly related to any organisms for which sequence data is currently available. If there exist any major, but so-far-undiscovered, deeply branching lineages in the tree of life, we suggest that methods such as those described herein currently offer the best way to search for them

A photo-responsive F-box protein FOF2 regulates floral initiation by promoting FLC expression in Arabidopsis.

Floral initiation is regulated by various genetic pathways in response to light, temperature, hormones and developmental status; however, the molecular mechanisms underlying the interactions between different genetic pathways are not fully understood. Here, we show that the photoresponsive gene FOF2 (F-box of flowering 2) negatively regulates flowering. FOF2 encodes a putative F-box protein that interacts specifically with ASK14, and its overexpression results in later flowering under both long-day and short-day photoperiods. Conversely, transgenic plants expressing the F-box domain deletion mutant of FOF2 (FOF2ΔF), or double loss of function mutant of FOF2 and FOL1 (FOF2-LIKE 1) present early flowering phenotypes. The late flowering phenotype of the FOF2 overexpression lines is suppressed by the flc-3 loss-of-function mutation. Furthermore, FOF2 mRNA expression is regulated by autonomous pathway gene FCA, and the repressive effect of FOF2 in flowering can be overcome by vernalization. Interestingly, FOF2 expression is regulated by light. The protein level of FOF2 accumulates in response to light, whereas it is degraded under dark conditions via the 26S proteasome pathway. Our findings suggest a possible mechanistic link between light conditions and the autonomous floral promotion pathway in Arabidopsis

T cell immunity rather than antibody mediates cross-protection against Zika virus infection conferred by a live attenuated Japanese encephalitis SA14-14-2 vaccine.

Zika virus (ZIKV) and Japanese encephalitis virus (JEV) are closely related to mosquito-borne flaviviruses. Japanese encephalitis (JE) vaccine SA14-14-2 has been in the Chinese national Expanded Program on Immunization since 2007. The recent recognition of severe disease syndromes associated with ZIKV, and the identification of ZIKV from mosquitoes in China, prompts an urgent need to investigate the potential interaction between the two. In this study, we showed that SA14-14-2 is protective against ZIKV infection in mice. JE vaccine SA14-14-2 triggered both Th1 and Th2 cross-reactive immune responses to ZIKV; however, it was cellular immunity that predominantly mediated cross-protection against ZIKV infection. Passive transfer of immune sera did not result in significant cross-protection but did mediate antibody-dependent enhancement in vitro, though this did not have an adverse impact on survival. This study suggests that the SA14-14-2 vaccine can protect against ZIKV through a cross-reactive T cell response. This is vital information in terms of ZIKV prevention or precaution in those ZIKV-affected regions where JEV circulates or SA14-14-2 is in widespread use, and opens a promising avenue to develop a novel bivalent vaccine against both ZIKV and JEV. KEY POINTS: • JEV SA14-14-2 vaccine conferred cross-protection against ZIKV challenge in mice. • T cell immunity rather than antibody mediated the cross-protection. • It provides important information in terms of ZIKV prevention or precaution

Knowledge, attitude, and practice of healthcare workers on early gastrointestinal cancer in China

ObjectiveGastrointestinal cancer is the leading cause of cancer-related death in China, and its early screening is largely recommended by healthcare workers. This study investigated the knowledge, attitudes, and practice (KAP) of healthcare workers on early gastrointestinal cancer (EGC).MethodsThis cross-sectional study was conducted on healthcare workers who volunteered to participate from 30 hospitals in China between September and December 2022. A self-administered questionnaire including 37 questions was developed.ResultsA total of 545 completed questionnaires were finally obtained. Healthcare workers had moderate knowledge level [9.22 ± 1.80 (65.88±12.89%), total score: 14], positive attitude [21.84 ± 2.67 (91.01 ± 11.14%), total score: 24], and excellent practice level [19.07 ± 4.43 (79.47 ± 18.44%), total score: 24] on EGC. Pearson's correlation analysis suggested that knowledge score was positively correlated with attitude (r = 0.264, P &lt; 0.001) and practice score (r = 0.140, P = 0.001), and higher attitude score was significantly correlated with higher practice score (r = 0.380, P &lt; 0.001), which were supported and reinforced by structural equation modeling. In addition, subgroup analysis showed that knowledge scores might be influenced by sex, age, education, type of hospital, type of occupation, professional title, and years of working (all P &lt; 0.05); attitude scores might be influenced by years of working (P &lt; 0.05); and practice scores were statistically distinct among groups of different sex, department, and years of working (all P &lt; 0.05).ConclusionHealthcare workers have moderate knowledge level, positive attitude, and excellent practice levels on EGC. Good knowledge and positive attitude might be correlated with excellent practice. KAP level might be influenced by sociodemographic characteristics