scholarly journals The evolutionary history of plant T2/S-type ribonucleases

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3790 ◽  
Author(s):  
Karolis Ramanauskas ◽  
Boris Igić
Keyword(s):  
Self Incompatibility ◽  
Class Iii ◽  
Widespread Occurrence ◽  
Public Resource ◽  
Core Eudicots ◽  
Evolutionary Context ◽  
Female Component ◽  
History Of ◽  
Genome Assemblies ◽  
Source Of Information

A growing number of T2/S-RNases are being discovered in plant genomes. Members of this protein family have a variety of known functions, but the vast majority are still uncharacterized. We present data and analyses of phylogenetic relationships among T2/S-RNases, and pay special attention to the group that contains the female component of the most widespread system of self-incompatibility in flowering plants. The returned emphasis on the initially identified component of this mechanism yields important conjectures about its evolutionary context. First, we find that the clade involved in self-rejection (class III) is found exclusively in core eudicots, while the remaining clades contain members from other vascular plants. Second, certain features, such as intron patterns, isoelectric point, and conserved amino acid regions, help differentiate S-RNases, which are necessary for expression of self-incompatibility, from other T2/S-RNase family members. Third, we devise and present a set of approaches to clarify new S-RNase candidates from existing genome assemblies. We use genomic features to identify putative functional and relictual S-loci in genomes of plants with unknown mechanisms of self-incompatibility. The widespread occurrence of possible relicts suggests that the loss of functional self-incompatibility may leave traces long after the fact, and that this manner of molecular fossil-like data could be an important source of information about the history and distribution of both RNase-based and other mechanisms of self-incompatibility. Finally, we release a public resource intended to aid the search for S-locus RNases, and help provide increasingly detailed information about their taxonomic distribution.

scholarly journals The evolutionary history of plant T2/S-type ribonucleases

2017 ◽  
Author(s):  
Karolis Ramanauskas ◽  
Boris Igić
Keyword(s):  
Self Incompatibility ◽  
Class Iii ◽  
Widespread Occurrence ◽  
Public Resource ◽  
Core Eudicots ◽  
Evolutionary Context ◽  
Female Component ◽  
History Of ◽  
Genome Assemblies ◽  
Source Of Information

A growing number of T2/S-RNases are being discovered in plant genomes. Members of this protein family have a variety of known functions, but the vast majority are still uncharacterized. We present data and analyses of phylogenetic relationships among T2/S-RNases, and pay special attention to the group that contains the female component of the most widespread system of self-incompatibility in flowering plants. The returned emphasis on the initially identified component of this mechanism yields important conjectures about its evolutionary context. First, we find that the clade involved in self-rejection (class III) is found exclusively in core eudicots, while the remaining clades contain members from other vascular plants. Second, certain features, such as intron patterns, isoelectric point, and conserved amino acid regions, help differentiate S-RNases, which are necessary for expression of self-incompatibility, from other T2/S-RNase family members. Third, we devise and present a set of approaches to clarify new S-RNase candidates from existing genome assemblies. We use genomic features to identify putative functional and relictual S-loci in genomes of plants with unknown mechanisms of self-incompatibility. The widespread occurrence of possible relicts suggests that the loss of functional self-incompatibility may leave traces long after the fact, and that this manner of molecular fossil-like data could be an important source of information about the history and distribution of both RNase-based and other mechanisms of self-incompatibility. Finally, we release a public resource intended to aid the search for S-locus RNases, and help provide increasingly detailed information about their taxonomic distribution.

scholarly journals The evolutionary history of plant T2/S-type ribonucleases

2017 ◽  
Author(s):  
Karolis Ramanauskas ◽  
Boris Igić
Keyword(s):  
Self Incompatibility ◽  
Class Iii ◽  
Widespread Occurrence ◽  
Public Resource ◽  
Core Eudicots ◽  
Evolutionary Context ◽  
Female Component ◽  
History Of ◽  
Genome Assemblies ◽  
Source Of Information

A growing number of T2/S-RNases are being discovered in plant genomes. Members of this protein family have a variety of known functions, but the vast majority are still uncharacterized. We present data and analyses of phylogenetic relationships among T2/S-RNases, and pay special attention to the group that contains the female component of the most widespread system of self-incompatibility in flowering plants. The returned emphasis on the initially identified component of this mechanism yields important conjectures about its evolutionary context. First, we find that the clade involved in self-rejection (class III) is found exclusively in core eudicots, while the remaining clades contain members from other vascular plants. Second, certain features, such as intron patterns, isoelectric point, and conserved amino acid regions, help differentiate S-RNases, which are necessary for expression of self-incompatibility, from other T2/S-RNase family members. Third, we devise and present a set of approaches to clarify new S-RNase candidates from existing genome assemblies. We use genomic features to identify putative functional and relictual S-loci in genomes of plants with unknown mechanisms of self-incompatibility. The widespread occurrence of possible relicts suggests that the loss of functional self-incompatibility may leave traces long after the fact, and that this manner of molecular fossil-like data could be an important source of information about the history and distribution of both RNase-based and other mechanisms of self-incompatibility. Finally, we release a public resource intended to aid the search for S-locus RNases, and help provide increasingly detailed information about their taxonomic distribution.

Analytical Electron Microscopy of Extraterrestrial Ice Analogs

1990 ◽  
Vol 48 (1) ◽  
pp. 594-595
Author(s):  
D.F. Blake ◽  
LJ. Allamandola ◽  
G. Palmer ◽  
A. Pohorille
Keyword(s):  
Solar System ◽  
Analytical Electron Microscopy ◽  
Biogenic Elements ◽  
Widespread Occurrence ◽  
Interstellar Ice ◽  
Analytical Electron ◽  
History Of ◽  
Interstellar Material ◽  
Astrophysical Ices ◽  
Interstellar Molecular Clouds

The natural history of the biogenic elements H, C, N, O, P and S in the cosmos is of great interest because it is these elements which comprise all life. Material ejected from stars (or pre-existing in the interstellar medium) is thought to condense into diffuse bodies of gravitationally bound gas and dust called cold interstellar molecular clouds. Current theories predict that within these clouds, at temperatures of 10-100° K, gases (primarily H2O, but including CO, CO2, CH3OH, NH3, and others) condense onto submicron silicate grains to form icy grain mantles. This interstellar ice represents the earliest and most primitive association of the biogenic elements. Within these multicomponent icy mantles, pre-biotic organic compounds are formed during exposure to UV radiation. It is thought that icy planetesimals (such as comets) within our solar system contain some pristine interstellar material, including ices, and may have (during the early bombardment of the solar system, ∼4 Ga) carried this material to Earth.Despite the widespread occurrence of astrophysical ices and their importance to pre-biotic organic evolution, few experimental data exist which address the relevant phase equilibria and possible structural states. A knowledge of the petrology of astrophysical ice analogs will allow scientists to more confidently interpret astronomical IR observations. Furthermore, the development and refinement of procedures for analyzing ices and other materials at cryogenic temperatures is critical to the study of materials returned from the proposed Rosetta comet nucleus and Mars sample return missions.

Correspondence between Adolphe Brongniart and Robert Schomburgk: trading natural history collections for honours

2002 ◽  
Vol 29 (3) ◽  
pp. 333-336
Author(s):  
PIOTR DASZKIEWICZ ◽  
MICHEL JEGU
Keyword(s):  
Nineteenth Century ◽  
Natural History ◽  
Dominican Republic ◽  
Southeast Asia ◽  
Herbarium Specimens ◽  
British Guiana ◽  
Natural History Collections ◽  
History Of ◽  
Source Of Information ◽  
German Naturalist

ABSTRACT: This paper discusses some correspondence between Robert Schomburgk (1804–1865) and Adolphe Brongniart (1801–1876). Four letters survive, containing information about the history of Schomburgk's collection of fishes and plants from British Guiana, and his herbarium specimens from Dominican Republic and southeast Asia. A study of these letters has enabled us to confirm that Schomburgk supplied the collection of fishes from Guiana now in the Laboratoire d'Ichtyologie, Muséum National d'Histoire Naturelle, Paris. The letters of the German naturalist are an interesting source of information concerning the practice of sale and exchange of natural history collections in the nineteenth century in return for honours.

scholarly journals A215 MDR3 DEFICIENCY MIMICKING WILSON DISEASE

2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 247-248
Author(s):  
M Flanagan ◽  
R Little ◽  
I Siddiqui ◽  
N Jones ◽  
V Ng
Keyword(s):  
Bile Acids ◽  
Wilson Disease ◽  
Genetic Disorder ◽  
Multi Drug Resistance ◽  
Total Serum ◽  
Cholestatic Liver Disease ◽  
Class Iii ◽  
Her Family ◽  
Abcb4 Gene ◽  
History Of

Abstract Background The chronic phenotype of ALF includes a broad differential diagnosis. Class III multi-drug resistance P-glycoprotein 3 (MDR3) deficiency, also referred to as progressive familial intrahepatic cholestasis type 3, is an autosomal recessive genetic disorder. It is caused by a defect on the ABCB4 gene located on chromosome 7, which encodes MDR3. MDR3 is responsible for transporting phosphatidylcholine across the canalicular membrane, thereby allowing it to be incorporated into bile micelles. MDR3 deficiency results in increased levels of free bile acids and detergent bile. Progressive cholangiopathy ensues from this detergent bile and indirectly leads to cholestasis and liver failure in severe cases. Significantly increased urinary and hepatic copper (Cu), which are hallmarks of Wilson disease, have also been reported in patients with acute hepatitis and cholestasis including patients with MDR3 deficiency Aims We report a case of a girl who presented with a chronic phenotype of PALF, who had multiple features of Wilson disease and so was treated as such until genetic analysis confirmed MDR3 deficiency Methods Results A 6 year old girl presented to the ED with a 1mth history of epistaxis and a 1wk history of abdominal pain and distension, facial edema, pallor and fever. Her family history was significant for parental consanguinity and maternal itch during pregnancy. On examination she had clubbing, scleral icterus and a distended abdomen with hepatosplenomegaly. Her bloodwork showed bicytopenia (HGB 53 & Plts 63) along with liver dysfunction (INR 2.9, albumin 25, conjugated bilirubin 9) and raised liver enzymes (transaminases & GGT >10xULN). Her total serum bile acids were raised at 134. An US showed hepatosplenomegaly with multiple hyperechoic nodules and perisplenic varices. She was extensively worked up for malignancy, autoimmune and metabolic disease. Serum ceruloplasmin was reduced, ophthalmology examination showed no KF rings and her 24hr urinary Cu was 10xULN. Liver Cu quantification was markedly raised at 40xULN. Liver biopsy showed cirrhosis with fibrosis related minimal non-specific portal and septal inflammation. Additionally, complete loss of canalicular staining on immunohistochemistry for MDR3 protein was noted, suggestive of MDR3 deficiency. Based on the Cu levels, a provisional diagnosis of Wilson disease was made and Cu chelation therapy was commenced pending genetic testing. A cholestatic gene panel subsequently showed homozygous pathogenic variant for the ABCB4 gene. Trientine was stopped and she was commenced on ursodeoxycholic acid. Though biochemically she remains largely unchanged, she is clinically stable whilst awaiting a liver transplant Conclusions This case highlights the diagnostic difficulties associated with Cu test result interpretation in patients with chronic cholestatic liver disease and urges a thorough consideration of alternative diagnoses of PALF Funding Agencies None

Effects of antiarrhythmic drugs on atrioventricular conduction in patients with preexisting bundle branch block

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Kochav ◽  
R.C Chen ◽  
J.M.D Dizon ◽  
J.A.R Reiffel
Keyword(s):  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Class I ◽  
Class Iii ◽  
Bundle Branch Block ◽  
Kaplan Meier ◽  
Cox Proportional Hazards Models ◽  
Hazard Ratios ◽  
History Of ◽  
Propensity Score Stratification

Abstract Background Theoretical concern exists regarding AV block (AVB) with class I antiarrhythmics (AADs) when bundle branch block (BBB) is present. Whether this is substantiated in real-world populations is unknown. Purpose To determine the relationship between type of AAD and incidence of AVB in patients with preexisting BBB. Methods We retrospectively studied all patients with BBB who received class I and III AADs between 1997–2019 to compare incidence of AVB. We defined index time as first exposure to either drug class and excluded patients with prior AVB or exposed to both classes. Time-at-risk window ended at first outcome occurrence or when patients were no longer observed in the database. We estimated hazard ratios for incident AVB using Cox proportional hazards models with propensity score stratification, adjusting for over 32,000 covariates from the electronic health record. Kaplan-Meier methods were used to determine treatment effects over time. Results Of 40,120 individuals with BBB, 148 were exposed to a class I AAD and 2401 to a class III AAD. Over nearly 4,200 person-years of follow up, there were 22 and 620 outcome events in the class I and class III cohorts, respectively (Figure). In adjusted analyses, AVB risk was markedly lower in patients exposed to class I AADs compared with class III (HR 0.48 [95% CI 0.30–0.75]). Conclusion Among patients with BBB, exposure to class III AADs was strongly associated with greater risk of incident AVB. This likely reflects differences in natural history of patients receiving class I vs class III AADs rather than adverse class III effects, however, the lack of worse outcomes acutely with class I AADs suggests that they may be safer in BBB than suspected. Funding Acknowledgement Type of funding source: None

scholarly journals Recombination and Selection at Brassica Self-Incompatibility Loci

Genetics ◽  
1999 ◽  
Vol 152 (1) ◽  
pp. 413-425 ◽  
Author(s):  
Philip Awadalla ◽  
Deborah Charlesworth
Keyword(s):  
Linkage Disequilibrium ◽  
Balancing Selection ◽  
Brassica Species ◽  
Selective Constraint ◽  
Intragenic Recombination ◽  
Self Incompatibility ◽  
History Of ◽  
Unknown Gene ◽  
Slg Gene ◽  
High Diversity

Abstract In Brassica species, self-incompatibility is controlled genetically by haplotypes involving two known genes, SLG and SRK, and possibly an as yet unknown gene controlling pollen incompatibility types. Alleles at the incompatibility loci are maintained by frequency-dependent selection, and diversity at SLG and SRK appears to be very ancient, with high diversity at silent and replacement sites, particularly in certain “hypervariable portions of the genes. It is important to test whether recombination occurs in these genes before inferences about function of different parts of the genes can be made from patterns of diversity within their sequences. In addition, it has been suggested that, to maintain the relationship between alleles within a given S-haplotype, recombination is suppressed in the S-locus region. The high diversity makes many population genetic measures of recombination inapplicable. We have analyzed linkage disequilibrium within the SLG gene of two Brassica species, using published coding sequences. The results suggest that intragenic recombination has occurred in the evolutionary history of these alleles. This is supported by patterns of synonymous nucleotide diversity within both the SLG and SRK genes, and between domains of the SRK gene. Finally, clusters of linkage disequilibrium within the SLG gene suggest that hypervariable regions are under balancing selection, and are not merely regions of relaxed selective constraint.

scholarly journals Prevalence of Malocclusion and Orthodontic Treatment Needs in Down Syndrome Sudanese Individuals

2014 ◽  
Vol 4 (2) ◽  
pp. 32-36
Author(s):  
Hiba A. Ibrahim ◽  
Amal H. Abuaffan
Keyword(s):  
Down Syndrome ◽  
Orthodontic Treatment ◽  
Class Iii ◽  
Class Iii Malocclusion ◽  
Treatment Needs ◽  
Angle Class ◽  
Alpha Level ◽  
History Of ◽  
Angle Class Iii Malocclusion ◽  
Angle Class Iii

Objective: To determine prevalence of malocclusion and orthodontic treatment needs in Down syndrome individuals among Sudanese population in Khartoum area.Materials & Method: A total of 75 (37 males and 38 females) Down syndrome individuals age ranging from 6-28 years were clinically examined after obtaining their guardian’s consent, malocclusion was determined based on Angle and Incisor classification. Exclusion criteria were included individuals who had history of extraction and orthodontic treatment.Data was analysed by using SPSS Version 17, at an alpha level 0.05 and 95% confidence limits.Result: Angle Class III and Incisor III malocclusion represents the most prevalent type of malocclusions (58.7%) Angle classification, (53.3%) Incisors classification. Angle Class III malocclusion was more frequent among females (60.5%) than in males (56.8%). Themajority of individuals with Down syndrome are in need of orthodontic treatment (85.3%).Conclusion: The prevalence of malocclusion and orthodontic treatment need among Sudanese Down syndrome individuals was high. Angle and Incisor Class III malocclusion representing commonest trait of malocclusion with more frequency in femalesthan males.Key word: down syndrome, Class III malocclusion, orthodontic treatment

scholarly journals The pink salmon genome: uncovering the genomic consequences of a strict two-year life-cycle

2021 ◽  
Author(s):  
Kris A. Christensen ◽  
Eric B. Rondeau ◽  
Dionne Sakhrani ◽  
Carlo A. Biagi ◽  
Hollie Johnson ◽  
...  
Keyword(s):  
Pacific Salmon ◽  
Pink Salmon ◽  
Chromosomal Polymorphism ◽  
Oncorhynchus Gorbuscha ◽  
Sequencing Data ◽  
Isolated Populations ◽  
Temporal Isolation ◽  
History Of ◽  
Genome Assemblies ◽  
Salmon Fishery

Pink salmon (Oncorhynchus gorbuscha) adults are the smallest of the five Pacific salmon native to the western Pacific Ocean. Pink salmon are also the most abundant of these species and account for a large proportion of the commercial value of the salmon fishery worldwide. A strict two-year life-history of most pink salmon generates temporally isolated populations that spawn either in even-years or odd-years. To uncover the influence of this genetic isolation, reference genome assemblies were generated for each year-class and whole genome re-sequencing data was collected from salmon of both year-classes. The salmon were sampled from six Canadian rivers and one Japanese river. At multiple centromeres we identified peaks of Fst between year-classes that were millions of base-pairs long. The largest Fst peak was also associated with a million base-pair chromosomal polymorphism found in the odd-year genome near a centromere. These Fst peaks may be the result of centromere drive or a combination of reduced recombination and genetic drift, and they could influence speciation. Other regions of the genome influenced by odd-year and even-year temporal isolation and tentatively under selection were mostly associated with genes related to immune function, organ development/maintenance, and behaviour.

scholarly journals Correction of severe facial asymmetry: A case with fractured condyle

2019 ◽  
Vol 9 ◽  
pp. 59-64
Author(s):  
Ramesh Agrawal ◽  
Dolly P. Patel ◽  
Bhagyashree B. Desai
Keyword(s):  
Facial Asymmetry ◽  
Post Treatment ◽  
Radiographic Examination ◽  
Rigid Fixation ◽  
Class Iii ◽  
Class Iii Malocclusion ◽  
History Of ◽  
Condylar Head ◽  
The Stability ◽  
The Right

The current paper depicts the challenges faced during the treatment of a complicated case of mandibular condylar head fracture, facial asymmetry, and centric relation-centric occlusion (CR-CO) discrepancy along with Class III malocclusion. A 20-year-old female reported with the chief complaint of difficulty in chewing and concern with her appearance due to deviated jaw and had a history of trauma over chin region. The clinical and radiographic examination revealed significant facial asymmetry with long face, right-sided deviation of the mandible, fractured condyle, CR-CO discrepancy, cross- bite with Class III malocclusion, and a missing mandibular single incisor along with non-vital 21 and 22. She was treated with 0.022 MBT appliance along with guiding plane for CR-CO correction followed by asymmetric bilateral sagittal split osteotomy and differential set back on the right and left sides and finally rigid fixation. A good facial profile and functional occlusion were achieved and non-vital 21 and 22 were esthetically rehabilitated with PFM crowns. The stability of surgical as well as orthodontic corrections was excellent and appreciable in the records obtained 2-year post-treatment. When faced with mutilated malocclusion, with multiple problems, sequential correction of functional malocclusion with dental decompensation followed by skeletal correction with surgical approach has yielded a appreciable facial correction with good stability showing 2-year post-treatment follow-up.

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