scholarly journals Unravelling the Complex Duplication History of Deuterostome Glycerol Transporters

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1663
Author(s):  
Ozlem Yilmaz ◽  
François Chauvigné ◽  
Alba Ferré ◽  
Frank Nilsen ◽  
Per Gunnar Fjelldal ◽  
...  

Transmembrane glycerol transport is an ancient biophysical property that evolved in selected subfamilies of water channel (aquaporin) proteins. Here, we conducted broad level genome (>550) and transcriptome (>300) analyses to unravel the duplication history of the glycerol-transporting channels (glps) in Deuterostomia. We found that tandem duplication (TD) was the major mechanism of gene expansion in echinoderms and hemichordates, which, together with whole genome duplications (WGD) in the chordate lineage, continued to shape the genomic repertoires in craniates. Molecular phylogenies indicated that aqp3-like and aqp13-like channels were the probable stem subfamilies in craniates, with WGD generating aqp9 and aqp10 in gnathostomes but aqp7 arising through TD in Osteichthyes. We uncovered separate examples of gene translocations, gene conversion, and concerted evolution in humans, teleosts, and starfishes, with DNA transposons the likely drivers of gene rearrangements in paleotetraploid salmonids. Currently, gene copy numbers and BLAST are poor predictors of orthologous relationships due to asymmetric glp gene evolution in the different lineages. Such asymmetries can impact estimations of divergence times by millions of years. Experimental investigations of the salmonid channels demonstrated that approximately half of the 20 ancestral paralogs are functional, with neofunctionalization occurring at the transcriptional level rather than the protein transport properties. The combined findings resolve the origins and diversification of glps over >800 million years old and thus form the novel basis for proposing a pandeuterostome glp gene nomenclature.


2014 ◽  
Vol 112 (5) ◽  
pp. 1493-1498 ◽  
Author(s):  
Fabio Cortesi ◽  
Zuzana Musilová ◽  
Sara M. Stieb ◽  
Nathan S. Hart ◽  
Ulrike E. Siebeck ◽  
...  

Single-gene and whole-genome duplications are important evolutionary mechanisms that contribute to biological diversification by launching new genetic raw material. For example, the evolution of animal vision is tightly linked to the expansion of the opsin gene family encoding light-absorbing visual pigments. In teleost fishes, the most species-rich vertebrate group, opsins are particularly diverse and key to the successful colonization of habitats ranging from the bioluminescence-biased but basically dark deep sea to clear mountain streams. In this study, we report a previously unnoticed duplication of the violet-blue short wavelength-sensitive 2 (SWS2) opsin, which coincides with the radiation of highly diverse percomorph fishes, permitting us to reinterpret the evolution of this gene family. The inspection of close to 100 fish genomes revealed that, triggered by frequent gene conversion between duplicates, the evolutionary history of SWS2 is rather complex and difficult to predict. Coincidentally, we also report potential cases of gene resurrection in vertebrate opsins, whereby pseudogenized genes were found to convert with their functional paralogs. We then identify multiple novel amino acid substitutions that are likely to have contributed to the adaptive differentiation between SWS2 copies. Finally, using the dusky dottyback Pseudochromis fuscus, we show that the newly discovered SWS2A duplicates can contribute to visual adaptation in two ways: by gaining sensitivities to different wavelengths of light and by being differentially expressed between ontogenetic stages. Thus, our study highlights the importance of comparative approaches in gaining a comprehensive view of the dynamics underlying gene family evolution and ultimately, animal diversification.



Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2077
Author(s):  
Oliver Zeman ◽  
Michael Schwenn ◽  
Martin Granig ◽  
Konrad Bergmeister

The assessment of already installed anchorages for a possible exceeding of the service load level is a question that is gaining more and more importance, especially in building maintenance. Bonded anchors are of particular interest here, as the detection of a capacity reduction or load exceedance can cause damage to the concrete-bonded mortar behavior. This article investigates the extent to which ultrasonic methods can be used to make a prediction about the condition of anchorages in concrete and about their load history. A promising innovative assessment method has been developed. The challenges in carrying out the experimental investigations are the arrangement of the transducers, the design of the test set-up and the applicability of direct, indirect or semidirect ultrasonic transmission. The experimental investigations carried out on a test concrete mix and a bonded anchor system show that damage to the concrete structure can be detected by means of ultrasound. The results indicate the formation of cracks and therefore a weakening of the response determined by means of direct, indirect and semidirect ultrasonic transmission. However, for application under non-laboratory conditions and on anchors with unknown load history, the calibration with a reference anchor and the identification of the maximum load is required. This enables a referencing of the other loaded anchors to the unloaded conditions and allows an estimation of the load history of individual anchors.



1990 ◽  
Vol 10 (6) ◽  
pp. 2513-2520
Author(s):  
L C Samuelson ◽  
K Wiebauer ◽  
C M Snow ◽  
M H Meisler

We have analyzed the junction regions of inserted elements within the human amylase gene complex. This complex contains five genes which are expressed at high levels either in the pancreas or in the parotid gland. The proximal 5'-flanking regions of these genes contain two inserted elements. A gamma-actin pseudogene is located at a position 200 base pairs upstream of the first coding exon. All of the amylase genes contain this insert. The subsequent insertion of an endogenous retrovirus interrupted the gamma-actin pseudogene within its 3'-untranslated region. Nucleotide sequence analysis of the inserted elements associated with each of the five human amylase genes has revealed a series of molecular events during the recent history of this gene family. The data indicate that the entire gene family was generated during primate evolution from one ancestral gene copy and that the retroviral insertion activated a cryptic promoter.



2003 ◽  
Vol 40 (01) ◽  
pp. 20-24
Author(s):  
Carl T. F. Ross ◽  
Ioannis Mourtos ◽  
George Papanikolaou

The paper reports on experimental investigations which have been made on three model RO/RO ferries. One of these was based on a 1/100th scale model of the Herald of Free Enterprise ferry. The other models were modified versions of the Herald of Free Enterprise which were so modified that they did not decrease the efficient concept of the throughput of a conventional vessel. One modified model had nine longitudinal compartments, while another had six longitudinal compartments; these vessels should meet SOLAS90+50 regulations. The RO/RO ferry models with nine and six compartments had considerably better damage stability characteristics than the conventional model. The experiments were carried out on all models without the consideration of waves and wind. Small weights were placed on the model ferries, to represent motor vehicles, and water was added on the car deck. Measurements of the resulting heel angles were taken. All results were plotted on graphs and they were compared and discussed. The effect of cargo shift on the transverse damage stability of these vessels was found to be significant. The paper also contains a brief history of a few very important RO/RO ferry accidents that have taken place since the end of the Second World War.



Hypertension ◽  
2000 ◽  
Vol 36 (suppl_1) ◽  
pp. 725-725
Author(s):  
Kazuko Masuo ◽  
Hiroshi Mikami ◽  
Toshio Ogihara ◽  
Michael L Tuck

P180 This study was conducted to clarify the differences in mechanisms between weight reduction (WR) sensitive and insensitive BP reduction, and to evaluate the contribution of family history of obesity (FH) to WR-induced BP reduction. In 61 obese hypertensive men (HT, 28.1±0.9 kg/m2, 35±3 years, 171±6/106±5 mmHg) and 52 obese normotensive men (NT, 27.9±0.6 kg/m2, 34±4 years, 131±5/83±4 mmHg), BMI, BP, fasting plasma norepinephrine (NE), angiotensin II (Ang II), PRA, leptin, insulin were measured every 2 week for 24 weeks with weight loss program (low caloric diet 1000kcal, 7gNaCl + excercise≥1 hr/day). WR and WR sensitive BP reduction were defined as >10% reduction in BMI or mean BP at week 12. 64% of HT and 63% of NT succeeded in WR, and 59% of HT with WR (sensitive vs insensitive P<.05) and 70% of NT with WR (P<.01) were sensitive in BP reduction. When FH+ was defined as at least one parent was obese (BMI>27.0 kg/m2), prevalence of FH+ was higher in 86% of HT and 95% of NT who failed in WR, and higher in 94% of HT and 80% of NT with WR insensitive BP reduction. Only the subjects who succeeded in WR were analyzed in this study. At entry, BP, NE, Ang II, PRA and insulin were higher in HT than in NT, although BMI and leptin were similar. However, the parameters at entry were similar between WR sensitive and insensitive BP reduction in each NT and HT. The decrements (Δ) in BP, NE, Ang II, leptin,insulin were significantly greater in subjects with WR sensitive BP reduction than subjects with WR insensitive BP reduction regardless of BP status during the study, although ΔBMI was similar. Significant decreases in the parameters were noted in earlier period in subjects with WR sensitive BP reduction than in subjects with insensitive BP reduction, and in NT than in HT. In the 4 study groups regardless of BP status or WR induced BP reduction, the decrease in NE preceded BP decline, and the decreases in Ang II, insulin, leptin & PRA followed BP decline with WR. These results suggest that a family history of obesity appears to contribute closely to resistance in weight loss and also to WR insensitive BP reduction. Suppression on sympathetic overactivity is a major mechanism in WR induced BP reduction.



1990 ◽  
Vol 10 (6) ◽  
pp. 2513-2520 ◽  
Author(s):  
L C Samuelson ◽  
K Wiebauer ◽  
C M Snow ◽  
M H Meisler

We have analyzed the junction regions of inserted elements within the human amylase gene complex. This complex contains five genes which are expressed at high levels either in the pancreas or in the parotid gland. The proximal 5'-flanking regions of these genes contain two inserted elements. A gamma-actin pseudogene is located at a position 200 base pairs upstream of the first coding exon. All of the amylase genes contain this insert. The subsequent insertion of an endogenous retrovirus interrupted the gamma-actin pseudogene within its 3'-untranslated region. Nucleotide sequence analysis of the inserted elements associated with each of the five human amylase genes has revealed a series of molecular events during the recent history of this gene family. The data indicate that the entire gene family was generated during primate evolution from one ancestral gene copy and that the retroviral insertion activated a cryptic promoter.



2020 ◽  
Vol 21 (2) ◽  
pp. 513 ◽  
Author(s):  
Marzia Tindara Venuto ◽  
Mathieu Decloquement ◽  
Joan Martorell Ribera ◽  
Maxence Noel ◽  
Alexander Rebl ◽  
...  

We identified and analyzed α2,8-sialyltransferases sequences among 71 ray-finned fish species to provide the first comprehensive view of the Teleost ST8Sia repertoire. This repertoire expanded over the course of Vertebrate evolution and was primarily shaped by the whole genome events R1 and R2, but not by the Teleost-specific R3. We showed that duplicated st8sia genes like st8sia7, st8sia8, and st8sia9 have disappeared from Tetrapods, whereas their orthologues were maintained in Teleosts. Furthermore, several fish species specific genome duplications account for the presence of multiple poly-α2,8-sialyltransferases in the Salmonidae (ST8Sia II-r1 and ST8Sia II-r2) and in Cyprinus carpio (ST8Sia IV-r1 and ST8Sia IV-r2). Paralogy and synteny analyses provided more relevant and solid information that enabled us to reconstruct the evolutionary history of st8sia genes in fish genomes. Our data also indicated that, while the mammalian ST8Sia family is comprised of six subfamilies forming di-, oligo-, or polymers of α2,8-linked sialic acids, the fish ST8Sia family, amounting to a total of 10 genes in fish, appears to be much more diverse and shows a patchy distribution among fish species. A focus on Salmonidae showed that (i) the two copies of st8sia2 genes have overall contrasted tissue-specific expressions, with noticeable changes when compared with human co-orthologue, and that (ii) st8sia4 is weakly expressed. Multiple sequence alignments enabled us to detect changes in the conserved polysialyltransferase domain (PSTD) of the fish sequences that could account for variable enzymatic activities. These data provide the bases for further functional studies using recombinant enzymes.



Author(s):  
Florian Schwarz

While both pragmatic theory and experimental investigations of language using psycholinguistic methods have been well-established subfields in the language sciences for a long time, the field of Experimental Pragmatics, where such methods are applied to pragmatic phenomena, has only fully taken shape since the early 2000s. By now, however, it has become a major and lively area of ongoing research, with dedicated conferences, workshops, and collaborative grant projects, bringing together researchers with linguistic, psychological, and computational approaches across disciplines. Its scope includes virtually all meaning-related phenomena in natural language comprehension and production, with a particular focus on what inferences utterances give rise to that go beyond what is literally expressed by the linguistic material. One general area that has been explored in great depth consists of investigations of various ‘ingredients’ of meaning. A major aim has been to develop experimental methodologies to help classify various aspects of meaning, such as implicatures and presuppositions as compared to basic truth-conditional meaning, and to capture their properties more thoroughly using more extensive empirical data. The study of scalar implicatures (e.g., the inference that some but not all students left based on the sentence Some students left) has served as a catalyst of sorts in this area, and they constitute one of the most well-studied phenomena in Experimental Pragmatics to date. But much recent work has expanded the general approach to other aspects of meaning, including presuppositions and conventional implicatures, but also other aspects of nonliteral meaning, such as irony, metonymy, and metaphors. The study of reference constitutes another core area of research in Experimental Pragmatics, and has a more extensive history of precursors in psycholinguistics proper. Reference resolution commonly requires drawing inferences beyond what is conventionally conveyed by the linguistic material at issue as well; the key concern is how comprehenders grasp the referential intentions of a speaker based on the referential expressions used in a given context, as well as how the speaker chooses an appropriate expression in the first place. Pronouns, demonstratives, and definite descriptions are crucial expressions of interest, with special attention to their relation to both intra- and extralinguistic context. Furthermore, one key line of research is concerned with speakers’ and listeners’ capacity to keep track of both their own private perspective and the shared perspective of the interlocutors in actual interaction. Given the rapid ongoing growth in the field, there is a large number of additional topical areas that cannot all be mentioned here, but the final section of the article briefly mentions further current and future areas of research.



2021 ◽  
Author(s):  
Giovanni Annona ◽  
Iori Sato ◽  
Juan Pascual-Anaya ◽  
Ingo Braasch ◽  
Randal Voss ◽  
...  

Nitric oxide (NO) is an ancestral key signaling molecule essential for life and has enormous versatility in biological systems, including cardiovascular homeostasis, neurotransmission, and immunity. Although our knowledge of nitric oxide synthases (Nos), the enzymes that synthesize NO in vivo, is substantial, the origin of a large and diversified repertoire of nos gene orthologs in fish with respect to tetrapods remains a puzzle. The recent identification of nos3 in the ray-finned fish spotted gar, which was considered lost in the ray-finned fish lineage, changed this perspective. This prompted us to explore nos gene evolution and expression in depth, surveying vertebrate species representing key evolutionary nodes. This study provides noteworthy findings: first, nos2 experienced several lineage-specific gene duplications and losses. Second, nos3 was found to be lost independently in two different teleost lineages, Elopomorpha and Clupeocephala. Third, the expression of at least one nos paralog in the gills of developing shark, bichir, sturgeon, and gar but not in arctic lamprey, suggest that nos expression in this organ likely arose in the last common ancestor of gnathostomes. These results provide a framework for continuing research on nos genes roles, highlighting subfunctionalization and reciprocal loss of function that occurred in different lineages during vertebrate genome duplications.



1987 ◽  
Vol 104 (2) ◽  
pp. 189-200 ◽  
Author(s):  
D R Finlay ◽  
D D Newmeyer ◽  
T M Price ◽  
D J Forbes

Selective transport of proteins is a major mechanism by which biochemical differences are maintained between the cytoplasm and nucleus. To begin to investigate the molecular mechanism of nuclear transport, we used an in vitro transport system composed of a Xenopus egg extract, rat liver nuclei, and a fluorescently labeled nuclear protein, nucleoplasmin. With this system, we screened for inhibitors of transport. We found that the lectin, wheat germ agglutinin (WGA), completely inhibits the nuclear transport of fluorescently labeled nucleoplasmin. No other lectin tested affected nuclear transport. The inhibition by WGA was not seen when N-acetylglucosamine was present and was reversible by subsequent addition of sugar. When rat liver nuclei that had been incubated with ferritin-labeled WGA were examined by electron microscopy, multiple molecules of WGA were found bound to the cytoplasmic face of each nuclear pore. Gel electrophoresis and nitrocellulose transfer identified one major and several minor nuclear protein bands as binding 125I-labeled WGA. The most abundant protein of these, a 63-65-kD glycoprotein, is a candidate for the inhibitory site of action of WGA on nuclear protein transport. WGA is the first identified inhibitor of nuclear protein transport and interacts directly with the nuclear pore.



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