scholarly journals The Evolution of Hemocyanin Genes in Caenogastropoda: Gene Duplications and Intron Accumulation in Highly Diverse Gastropods

2021 ◽  
Author(s):  
Gabriela Giannina Schäfer ◽  
Lukas Jörg Grebe ◽  
Robin Schinkel ◽  
Bernhard Lieb
Keyword(s):  
Adaptive Radiation ◽  
Gene Evolution ◽  
Abiotic Factors ◽  
Oxygen Affinity ◽  
Pomacea Canaliculata ◽  
Gene Duplications ◽  
Phylogenetic Groups ◽  
Physiological Factor ◽  
Multiple Gene ◽  
Starting Point

AbstractHemocyanin is the oxygen transport protein of most molluscs and represents an important physiological factor that has to be well-adapted to their environments because of the strong influences of abiotic factors on its oxygen affinity. Multiple independent gene duplications and intron gains have been reported for hemocyanin genes of Tectipleura (Heterobranchia) and the caenogastropod species Pomacea canaliculata, which contrast with the uniform gene architectures of hemocyanins in Vetigastropoda. The goal of this study was to analyze hemocyanin gene evolution within the diverse group of Caenogastropoda in more detail. Our findings reveal multiple gene duplications and intron gains and imply that these represent general features of Apogastropoda hemocyanins. Whereas hemocyanin exon–intron structures are identical within different Tectipleura lineages, they differ strongly within Caenogastropoda among phylogenetic groups as well as between paralogous hemocyanin genes of the same species. Thus, intron accumulation took place more gradually within Caenogastropoda but finally led to a similar consequence, namely, a multitude of introns. Since both phenomena occurred independently within Heterobranchia and Caenogastropoda, the results support the hypothesis that introns may contribute to adaptive radiation by offering new opportunities for genetic variability (multiple paralogs that may evolve differently) and regulation (multiple introns). Our study indicates that adaptation of hemocyanin genes may be one of several factors that contributed to the evolution of the large diversity of Apogastropoda. While questions remain, this hypothesis is presented as a starting point for the further study of hemocyanin genes and possible correlations between hemocyanin diversity and adaptive radiation.

Vegetation structure of tundra and taiga on the map of the natural vegetation of Europe

2007 ◽  
pp. 13-22 ◽  
Author(s):  
T. K. Yurkovskaya
Keyword(s):  
Vegetation Cover ◽  
Abiotic Factors ◽  
Self Regulation ◽  
Space Structure ◽  
Middle Taiga ◽  
Russian Plain ◽  
Forest Communities ◽  
The North ◽  
Tundra Vegetation ◽  
Starting Point

I have focused only on some features of structure in the taiga vegetation cover. In conclusion I would like to tell some words about the causes of complicated space structure of the taiga and tundra vegetation cover. The causes of latitudinal differentiation are climatic undoubtedly, but heterogeneity of vegetation cover within the limits of tundra and taiga subzones is accounted for different factors. In tundra abiogenic factors prevail, first of all the permafrost processes. That is the reason why tundra vegetation cover is so sensible to any disturbances and so hard regenerates after various transformations. In taiga the space structure is mostly the result of self-regulation and self- restoration of biota. The abiotic factors, certainly, play significant role, but they recede to the second plan. So we showed that in the north and middle taiga the structure of vegetation cover, during the Holocene up to present time, is determined in many respects by the increasing role of mires. Suffice it to look at the map of distribution of mires in order to estimate their role in vegetation cover of the easteuropean taiga (Yurkovskaya, 1980). So, the increase of mire area on the Russian Plain in m2/year per 1000 ha varies between 200 and 700, the average increas is ca 300—400 m2/year (Elina et all., 2000). The mires favour peniplenization and unite the separate areas of forest communities into the whole by means of forming the buffer paludificated territories (various hydrophilous variants of forest communities). But if mires, at all their stability, after destroying practically don't restore, the forests even after continuous cuttings restore their structure and composition through the series of successional stages unless an ecotope is damaged completely. Hence the space structure of taiga is the result, first of all, self development and self regulation of its vegetation cover. But, as it is known, at present time the process of destruction of natural biota has gone too far that the question arises not only about supporting its state and structure but also about the survival of the mankind itself. In this regard the vegetation map of Europe is the invaluable basis, which gives the starting point for all conservational, ecological and economical measures. But it is important to learn reading and using the map. And this is one of our actual goals.

Enzyme Promiscuous Activity: How to Define it and its Evolutionary Aspects

2020 ◽  
Vol 27 (5) ◽  
pp. 400-410
Author(s):  
Valentina De Luca ◽  
Luigi Mandrich
Keyword(s):  
Gene Evolution ◽  
Sequence Divergence ◽  
High Specificity ◽  
Industrial Applications ◽  
Point Of View ◽  
Enzyme Promiscuity ◽  
Primary Activity ◽  
Starting Point ◽  
Main Activity

: Enzymes are among the most studied biological molecules because better understanding enzymes structure and activity will shed more light on their biological processes and regulation; from a biotechnological point of view there are many examples of enzymes used with the aim to obtain new products and/or to make industrial processes less invasive towards the environment. Enzymes are known for their high specificity in the recognition of a substrate but considering the particular features of an increasing number of enzymes this is not completely true, in fact, many enzymes are active on different substrates: this ability is called enzyme promiscuity. Usually, promiscuous activities have significantly lower kinetic parameters than to that of primary activity, but they have a crucial role in gene evolution. It is accepted that gene duplication followed by sequence divergence is considered a key evolutionary mechanism to generate new enzyme functions. In this way, promiscuous activities are the starting point to increase a secondary activity in the main activity and then get a new enzyme. The primary activity can be lost or reduced to a promiscuous activity. In this review we describe the differences between substrate and enzyme promiscuity, and its rule in gene evolution. From a practical point of view the knowledge of promiscuity can facilitate the in vitro progress of proteins engineering, both for biomedical and industrial applications. In particular, we report cases regarding esterases, phosphotriesterases and cytochrome P450.

Features of ozone effect on oxygen-dependent processes in the blood under hypoxic conditions

2021 ◽  
Vol 20 (3) ◽  
pp. 70-76
Author(s):  
V. V. Zinchuk ◽  
E. S. Biletskaya
Keyword(s):  
Malonic Dialdehyde ◽  
Oxygen Affinity ◽  
Diene Conjugates ◽  
Physiological Factor ◽  
Sodium Hydrosulfide ◽  
Hypoxic Conditions ◽  
Hemoglobin Oxygen Affinity ◽  
Gaseous Transmitters ◽  
Dependent Processes

Introduction. Ozone is a physiological factor that can change hemoglobin oxygen affinity and the formation of gaseous transmitters (NO, H2S). The aim is to study the effect of ozone with gaseous transmitters donors on oxygen-dependent processes in the blood under hypoxic conditions in vitro. Materials and methods. Blood samples were divided into 6 groups of 3 ml each. Groups 2, 4, 5, 6 were pretreated with a deoxygenating gas mixture (5.5 % CO2; 94.5 % N2). In groups 3, 4, 5, 6, ozonized isotonic sodium chloride solution (with an ozone concentration of 6 mg/l) was added, and in groups 5 and 6, the donors of gas transmitters nitroglycerin and sodium hydrosulfide, respectively, were additionally introduced. Results. Pre-deoxygenation reduces the effect of ozone on oxygen transport in the blood. Nitroglycerin prevents this effect. The action of ozone under hypoxic conditions leads to an increase of content of NO3-/NO2- and H2S, and combination with nitroglycerin and sodium hydrosulfide increase these parameters. Deoxygenation due to ozone reduces parameters of lipid peroxidation (malonic dialdehyde, diene conjugates), retinol and α-tocopherol, and the same result in the nitroglycerin group. Conclusion. Under hypoxic conditions, a decrease in the effect of ozone on oxygen-dependent processes is reported. Nitroglycerin reduces its manifestation, while sodium hydrosulfide does not have a similar effect.

scholarly journals Accelerated regulatory gene evolution in an adaptive radiation

2001 ◽  
Vol 98 (18) ◽  
pp. 10208-10213 ◽  
Author(s):  
M. Barrier ◽  
R. H. Robichaux ◽  
M. D. Purugganan
Keyword(s):  
Adaptive Radiation ◽  
Gene Evolution ◽  
Regulatory Gene

scholarly journals Reconciliation of Gene and Species Trees

2014 ◽  
Vol 2014 ◽  
pp. 1-22 ◽  
Author(s):  
L. Y. Rusin ◽  
E. V. Lyubetskaya ◽  
K. Y. Gorbunov ◽  
V. A. Lyubetsky
Keyword(s):  
Time Scales ◽  
Gene Evolution ◽  
Single Species ◽  
Species Tree ◽  
Gene Duplications ◽  
Species Trees ◽  
Evolutionary Scenario ◽  
Algorithmic Construction ◽  
Basic Ideas ◽  
Horizontal Transfers

The first part of the paper briefly overviews the problem of gene and species trees reconciliation with the focus on defining and algorithmic construction of the evolutionary scenario. Basic ideas are discussed for the aspects of mapping definitions, costs of the mapping and evolutionary scenario, imposing time scales on a scenario, incorporating horizontal gene transfers, binarization and reconciliation of polytomous trees, and construction of species trees and scenarios. The review does not intend to cover the vast diversity of literature published on these subjects. Instead, the authors strived to overview the problem of the evolutionary scenario as a central concept in many areas of evolutionary research. The second part provides detailed mathematical proofs for the solutions of two problems: (i) inferring a gene evolution along a species tree accounting for various types of evolutionary events and (ii) trees reconciliation into a single species tree when only gene duplications and losses are allowed. All proposed algorithms have a cubic time complexity and are mathematically proved to find exact solutions. Solving algorithms for problem (ii) can be naturally extended to incorporate horizontal transfers, other evolutionary events, and time scales on the species tree.

scholarly journals Egg perivitelline fluid of the invasive snail Pomacea canaliculata affects mice gastrointestinal function and morphology

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5314 ◽  
Author(s):  
Matías Giglio ◽  
Cintia Garro ◽  
Enrique Caviedes-Vidal ◽  
Horacio Heras
Keyword(s):  
Small Intestine ◽  
Abiotic Factors ◽  
Nutrient Absorption ◽  
Proximal Portion ◽  
Pomacea Canaliculata ◽  
Dependent Manner ◽  
Apple Snail ◽  
Gut Permeability ◽  
South Central ◽  
Perivitelline Fluid

Background Species beloging to the genus Pomacea (Ampullariidae), often referred as apple snails, are freshwater, amphibious snails native to South, Central and North America. Some species such as P. canaliculata have become a driver of ecosystem changes in wetlands and an important rice and taro pest after its introduction to Asia and other parts of the world. Females deposit colored egg clutches above the waterline, a reproductive strategy that exposes the eggs to harsh conditions and terrestrial predation. However, eggs have no reported predators in their native range, probably because of the acquisition of unparalleled biochemical defenses provided by a set of proteins (perivitellins) that nourish embryos and protect them from predators and abiotic factors. Notably, ingestion of egg perivitelline fluid (PVF) decreases rat growth rate and alters their gastrointestinal morphology. The aim of the study is to determine the effect of apple snail egg PVF on mice gut digestive activity, morphology and nutrient absorption. Methods Carbohydrate digestion by intestinal disaccharidases (sucrase-isomaltase and maltase-glucoamylase) was evaluated ex vivo in mice gavaged with 1 or 4 doses of PVF. Changes in gut morphological and absorptive surface were measured. In addition, alteration on nutrient absorption rates, transport pathways and intestinal permeability was evaluated by luminal perfusions of small intestine with radiolabeled L-proline (absorbed by paracellular and transcellular pathways) and L-arabinose (absorbed exclusively by paracellular pathway). Results Perivitelline fluid affected mice displayed significant morphological changes in the small intestine epithelium inducing the appearance of shorter and wider villi as well as fused villi. This resulted in a diminished absorptive surface, notably in the proximal portion. Likewise, the activity of disaccharidases diminished in the proximal portion of the intestine. Total absorption of L-proline increased in treated mice in a dose-dependent manner. There were no differences neither in the ratio of paracellular-to-transcellular absorption of L-proline nor in gut permeability as revealed by the clearance of L-arabinose. Discussion Oral administration of apple snail PVF to mice adversely alters gut morphophysiology by reducing the intestinal absorptive surface, affecting enzymes of sugar metabolism and increasing the absorption rate of nutrients without affecting the relative contribution of the absorption pathways or gut permeability. These results further support the role of PVF in passive anti-predator defenses in Pomacea snail eggs that target the digestive system.

scholarly journals Isolation and Identification of Dominant Bacteria From Black Soldier Fly Larvae (Hermetia illucens) Envisaging Practical Applications

2021 ◽  
Vol 12 ◽  
Author(s):  
Ellen Gorrens ◽  
Laurence Van Moll ◽  
Lotte Frooninckx ◽  
Jeroen De Smet ◽  
Leen Van Campenhout
Keyword(s):  
Abiotic Factors ◽  
Functional Characterization ◽  
Isolation And Identification ◽  
Black Soldier Fly ◽  
Hermetia Illucens ◽  
Strain Collection ◽  
Starting Point ◽  
Black Soldier Fly Larvae ◽  
Fly Larvae ◽  
Dominant Bacteria

This study aimed to establish a representative strain collection of dominant aerobic bacteria from black soldier fly larvae (Hermetia illucens, BSFL). The larvae were fed either chicken feed or fiber-rich substrates to obtain a collection of BSFL-associated microorganisms. Via an approach based on only considering the highest serial dilutions of BSFL extract (to select for the most abundant strains), a total of 172 bacteria were isolated. Identification of these isolates revealed that all bacteria belonged to either the Proteobacteria (66.3%), the Firmicutes (30.2%), the Bacteroidetes (2.9%) or the Actinobacteria (0.6%). Twelve genera were collected, with the most abundantly present ones (i.e., minimally present in at least three rearing cycles) being Enterococcus (29.1%), Escherichia (22.1%), Klebsiella (19.8%), Providencia (11.6%), Enterobacter (7.6%), and Morganella (4.1%). Our collection of dominant bacteria reflects largely the bacterial profiles of BSFL already described in literature with respect to the most important phyla and genera in the gut, but some differences can be noticed depending on substrate, biotic and abiotic factors. Furthermore, this bacterial collection will be the starting point to improve in vitro digestion models for BSFL, to develop mock communities and to find symbionts that can be added during rearing cycles to enhance the larval performances, after functional characterization of the isolates, for instance with respect to enzymatic potential.

scholarly journals Egg perivitelline fluid of the invasive snail Pomacea canaliculata affects mice gastrointestinal function and morphology

2018 ◽  
Author(s):  
Matías Giglio ◽  
Cintia Garro ◽  
Enrique Caviedes-Vidal ◽  
Horacio Heras
Keyword(s):  
Small Intestine ◽  
Morphological Changes ◽  
Abiotic Factors ◽  
Nutrient Absorption ◽  
Proximal Portion ◽  
Pomacea Canaliculata ◽  
Dependent Manner ◽  
Apple Snail ◽  
Gut Permeability ◽  
Perivitelline Fluid

Background. Pomacea Apple snails are freshwater, amphibious snails native from South America. Some species such as P. canaliculata have become a driver of ecosystemic changes in wetlands and an important rice and taro pest after its introduction to Asia and other parts of the world. Females deposit colored eggs clutches above the waterline, a reproductive strategy that exposes the eggs to harsh conditions and terrestrial predation. However, eggs have no reported predators in their native range, probably by the acquisition of unparalleled biochemical defenses based on a set of proteins (perivitellins) that nourish embryos and protect them from predators and abiotic factors. Notably, ingestion of egg perivitelline fluid (PVF) decreases rat growth rate and alters their gastrointestinal morphology. The aim of the study is to determine the effect of apple snail egg PVF on mice gut digestive activity, morphology and nutrient absorption. Methods. Carbohydrate digestion by intestinal disaccharidases (sucrase-isomaltase and maltase-glucoamilase) was evaluated ex vivo in mice gavaged with 1 or 4 doses of PVF. Gut morphological changes and absorptive surface were also determined. In addition, alteration on nutrient absorption rates, transport pathways and intestinal permeability was evaluated by luminal perfusions of small intestine with radiolabeled L-proline (absorbed by paracellular and transcellular pathways) and L-arabinose (absorbed exclusively by paracellular pathway). Results. PVF affected mice which displayed large morphological changes in the small intestine epithelium inducing the appearance of shorter and wider villi as well as fused villi. This resulted in a diminished absorptive surface, notably in the proximal portion. Likewise, the activity of disaccharidases diminished in the proximal portion of the intestine. Total absorption of L-proline increased in treated mice in a dose-dependent manner. There were no differences neither in the ratio paracellular-to-transcellular absorption of L-proline nor in gut permeability as revealed by the clearance of L-arabinose. Discussion. Oral administration of apple snail PVF to mice adversely alters gut morphophysiology by reducing the intestinal absorptive surface, affecting enzymes of sugar metabolism and increasing the absorption rate of nutrients without affecting the relative contribution of the absorption pathways or gut permeability. These results further support the notion that Pomacea snail eggs possess a passive anti-predator defense targeting the digestive system

scholarly journals Egg perivitelline fluid of the invasive snail Pomacea canaliculata affects mice gastrointestinal function and morphology

2018 ◽  
Author(s):  
Matías Giglio ◽  
Cintia Garro ◽  
Enrique Caviedes-Vidal ◽  
Horacio Heras
Keyword(s):  
Small Intestine ◽  
Morphological Changes ◽  
Abiotic Factors ◽  
Nutrient Absorption ◽  
Proximal Portion ◽  
Pomacea Canaliculata ◽  
Dependent Manner ◽  
Apple Snail ◽  
Gut Permeability ◽  
Perivitelline Fluid

Background. Pomacea Apple snails are freshwater, amphibious snails native from South America. Some species such as P. canaliculata have become a driver of ecosystemic changes in wetlands and an important rice and taro pest after its introduction to Asia and other parts of the world. Females deposit colored eggs clutches above the waterline, a reproductive strategy that exposes the eggs to harsh conditions and terrestrial predation. However, eggs have no reported predators in their native range, probably by the acquisition of unparalleled biochemical defenses based on a set of proteins (perivitellins) that nourish embryos and protect them from predators and abiotic factors. Notably, ingestion of egg perivitelline fluid (PVF) decreases rat growth rate and alters their gastrointestinal morphology. The aim of the study is to determine the effect of apple snail egg PVF on mice gut digestive activity, morphology and nutrient absorption. Methods. Carbohydrate digestion by intestinal disaccharidases (sucrase-isomaltase and maltase-glucoamilase) was evaluated ex vivo in mice gavaged with 1 or 4 doses of PVF. Gut morphological changes and absorptive surface were also determined. In addition, alteration on nutrient absorption rates, transport pathways and intestinal permeability was evaluated by luminal perfusions of small intestine with radiolabeled L-proline (absorbed by paracellular and transcellular pathways) and L-arabinose (absorbed exclusively by paracellular pathway). Results. PVF affected mice which displayed large morphological changes in the small intestine epithelium inducing the appearance of shorter and wider villi as well as fused villi. This resulted in a diminished absorptive surface, notably in the proximal portion. Likewise, the activity of disaccharidases diminished in the proximal portion of the intestine. Total absorption of L-proline increased in treated mice in a dose-dependent manner. There were no differences neither in the ratio paracellular-to-transcellular absorption of L-proline nor in gut permeability as revealed by the clearance of L-arabinose. Discussion. Oral administration of apple snail PVF to mice adversely alters gut morphophysiology by reducing the intestinal absorptive surface, affecting enzymes of sugar metabolism and increasing the absorption rate of nutrients without affecting the relative contribution of the absorption pathways or gut permeability. These results further support the notion that Pomacea snail eggs possess a passive anti-predator defense targeting the digestive system

Locating Multiple Gene Duplications through Reconciled Trees

2008 ◽  
pp. 273-284 ◽  
Author(s):  
J. Gordon Burleigh ◽  
Mukul S. Bansal ◽  
Andre Wehe ◽  
Oliver Eulenstein
Keyword(s):  
Gene Duplications ◽  
Multiple Gene
Sign in / Sign up

Export Citation Format

Share Document