The mapping of functional genes plays an important role in studies of genome structure, function, and evolution, as well as allowing gene cloning and marker-assisted selection to improve agriculturally important traits. Simple sequence repeats (SSRs) developed from expressed sequence tags (ESTs), EST-SSR (eSSR), can be employed as putative functional marker loci to easily tag corresponding functional genes. In this paper, 2218 eSSRs, 1554 from G. raimondii-derived and 754 from G. hirsutum-derived ESTs, were developed and used to screen polymorphisms to enhance our backbone genetic map in allotetraploid cotton. Of the 1554 G. raimondii-derived eSSRs, 744 eSSRs were able to successfully amplify polymorphisms between our two mapping parents, TM-1 and Hai7124, presenting a polymorphic rate of 47.9%. However, only a 23.9% (159/754) polymorphic rate was produced from G. hirsutum-derived eSSRs. No relationship was observed between the level of polymorphism, motif type, and tissue origin, but the polymorphism appeared to be correlated with repeat type. After integrating these new eSSRs, our enhanced genetic map consists of 1790 loci in 26 linkage groups and covers 3425.8 cM with an average intermarker distance of 1.91 cM. This microsatellite-based, gene-rich linkage map contains 71.96% functional marker loci, of which 87.11% are eSSR loci. There were 132 duplicated loci bridging 13 homeologous At/Dt chromosome pairs. Two reciprocal translocations after polyploidization between A2 and A3, and between A4 and A5, chromosomes were further confirmed. A functional analysis of 975 ESTs producing 1122 eSSR loci tagged in the map revealed that 60% had clear BLASTX hits (,1e À10 ) to the Uniprot database and that 475 were associated mainly with genes belonging to the three major gene ontology categories of biological process, cellular component, and molecular function; many of the ESTs were associated with two or more category functions. The results presented here will provide new insights for future investigations of functional and evolutionary genomics, especially those associated with cotton fiber improvement.
The Saccharomyces cerevisiae Pif1 protein (ScPif1p) is the prototypical member of the Pif1 family of DNA helicases. ScPif1p is involved in the maintenance of mitochondrial, ribosomal and telomeric DNA and suppresses genome instability at G-quadruplex motifs. Here, we report the crystal structures of a truncated ScPif1p (ScPif1p237−780) in complex with different ssDNAs. Our results have revealed that a yeast-specific insertion domain protruding from the 2B domain folds as a bundle bearing an α-helix, α16. The α16 helix regulates the helicase activities of ScPif1p through interactions with the previously identified loop3. Furthermore, a biologically relevant dimeric structure has been identified, which can be further specifically stabilized by G-quadruplex DNA. Basing on structural analyses and mutational studies with DNA binding and unwinding assays, a potential G-quadruplex DNA binding site in ScPif1p monomers is suggested. Our results also show that ScPif1p uses the Q-motif to preferentially hydrolyze ATP, and a G-rich tract is preferentially recognized by more residues, consistent with previous biochemical observations. These findings provide a structural and mechanistic basis for understanding the multifunctional ScPif1p.
In this work, polyacrylonitrile (PAN)/graphene oxide (GO) composite nanofibers were prepared by a facile compounding and electrospinning processes. A small amount of GO powders were first dispersed in N,N-dimethylformamide by sonication, and then, PAN powders were added to prepare an electrospinning solution. The surface morphology was analyzed by atomic force microscopy and transmission electron microscopy, whereas the chemical properties of the PAN and PAN/GO composite nanofibers were compared by infrared (IR) spectroscopy. Also, lateral force microscopy and force-distance curves (FDC) were employed to investigate the surface properties, such as friction force and elasticity. The experimental results indicate that with increasing GO concentration, the surface friction force and adhesive force increased, so the nanofibers showed promise for applications as supports for enzyme immobilization.
Background: Retinopathy of pre-maturity (ROP) is a disorder of the retinal blood vessels in pre-term infants with low birth weight. It is a leading cause of blindness in children. During ROP screening, the use of mydriatic drops and eyelid openers causes pain and discomfort. Pain management strategies include medications and behavioral interventions. The objectives of this study was to investigate the effects of Gentle Human Touch on pain in pre-term infants undergoing screening for ROP.Methods: In this randomized controlled trial, 82 infants in the neonatal intensive care unit at Children's Hospital of Nanjing Medical University who met the ROP screening criteria were randomly assigned to experimental and control groups using the random number table. The infants in the experimental group continuously received Gentle Human Touch during screening, while those in the control group were screened according to the routine procedure. All neonates were administered local eye anesthesia before the screening. The degree of pain was assessed using the Pre-mature Infant Pain Profile score. A double-channel near-infrared spectroscopy device was used to monitor regional cerebral oxygen saturation (rScO2), while oxygen saturation (SaO2) and heart rate were measured using pulse oximetry. The Pre-mature Infant Pain Profile score was the primary outcome, while heart rate, SaO2, and rScO2 were the secondary outcomes.Results: The gestational age, corrected gestational age, birth weight, and Apgar score at examination and the basal heart rate, SaO2, and rScO2 showed no significant intergroup differences (P > 0.05 for all). Both groups demonstrated significant decreases in SaO2 and rScO2 in response to the examination (P < 0.05 for all). During the examination, the Pre-mature Infant Pain Profile score (14.82 ± 3.22 vs. 9.29 ± 2.89, respectively; P < 0.05) was significantly higher in the control group than in the experimental group, while rScO2 (57.61 ± 3.51 vs. 54.76 ± 4.54%, respectively; P < 0.05) and SaO2 (91.89 ± 6.43 vs. 85.68 ± 8.31%; P < 0.05) were significantly higher in the experimental group than in the control group. There was no significant difference in heart rate changes between the two groups before and after the examination (182.60 ± 3.50 vs. 170.80 ± 3.50 time/min; P > 0.05).Conclusions: The findings of this study suggest that Gentle Human Touch can effectively alleviate pain during ROP screening in pre-mature infants.Clinical Trial Registration: ISRCTN10976481, Registered 06 March 2020, Retrospectively registered.
Cry toxins are insecticidal toxin proteins produced by a spore-forming Gram-positive bacterium Bacillus thuringiensis. Interactions between the Cry toxins and the receptors from midgut brush border membrane vesicles (BBMVs), such as cadherin, alkaline phosphatase, and aminopeptidase, are key steps for the specificity and insecticidal activity of Cry proteins. However, little is known about the midgut juice proteins that may interfere with Cry binding to the receptors. To validate the hypothesis that there exist Cry-binding proteins that can interfere with the insecticidal process of Cry toxins, we applied Cry1Ab1-coupled Sepharose beads to isolate Cry-binding proteins form midgut juice of Plutella xylostella and Spodoptera exigua. Trypsin-like serine proteases and Dorsal were found to be Cry1Ab1-binding proteins in the midgut juice of P. xylostella. Peroxidase-C (POX-C) was found to be the Cry1Ab1-binding protein in the midgut juice of S. exigua. We proposed possible insecticidal mechanisms of Cry1Ab1 mediated by the two immune-related proteins: Dorsal and POX-C. Our results suggested that there exist, in the midgut juice, Cry-binding proteins, which are different from BBMV-specific receptors.
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