Maternal provisioning of sequestered defensive steroids by the Asian snake Rhabdophis tigrinus

Chemoecology ◽  
2008 ◽  
Vol 18 (3) ◽  
pp. 181-190 ◽  
Author(s):  
Deborah A. Hutchinson ◽  
Alan H. Savitzky ◽  
Akira Mori ◽  
Jerrold Meinwald ◽  
Frank C. Schroeder
Keyword(s):  
Maternal Provisioning ◽  
Rhabdophis Tigrinus

scholarly journals Active foraging for toxic prey during gestation in a snake with maternal provisioning of sequestered chemical defences

2015 ◽  
Vol 282 (1798) ◽  
pp. 20142137 ◽  
Author(s):  
Yosuke Kojima ◽  
Akira Mori
Keyword(s):  
Chemical Cues ◽  
Chemical Defence ◽  
Stomach Contents ◽  
Direct Proportion ◽  
Chemical Defences ◽  
Y Maze ◽  
Maternal Provisioning ◽  
Behavioural Switching ◽  
Rhabdophis Tigrinus ◽  
Gravid Females

Many animals sequester dietary defensive compounds and incorporate them into the offspring, which protects the young against predation. One possible but poorly investigated question is whether females of such species actively prey upon toxic diets. The snake Rhabdophis tigrinus sequesters defensive steroids from toads consumed as prey; it also feeds on other amphibians. Females produce chemically armed offspring in direct proportion to their own level of toad-derived toxins by provisioning the toxins to their eggs. Our field observations of movements and stomach contents of radio-tracked R. tigrinus showed that gravid snakes preyed upon toads by actively foraging in the habitat of toads, even though toads were a scarce resource and toad-searching may incur potential costs. Our Y-maze experiments demonstrated that gravid females were more likely to trail the chemical cues of toads than were males or non-gravid females. These results showed behavioural switching in females and active foraging for scarce, toxic prey during gestation. Because exploitation of toads by gravid females results in their offspring being more richly endowed with prey-derived toxins, active foraging for toxic prey is expected to be an adaptive antipredator trait, which may enhance chemical defence in offspring.

scholarly journals Attempt to Develop Rat Disseminated Intravascular Coagulation Model Using Yamakagashi (Rhabdophis tigrinus) Venom Injection

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 160
Author(s):  
Akihiko Yamamoto ◽  
Takashi Ito ◽  
Toru Hifumi
Keyword(s):  
Disseminated Intravascular Coagulation ◽  
Clinical Condition ◽  
Underlying Disease ◽  
Fibrinogen Concentration ◽  
Blood Coagulation Factors ◽  
Fixed Amount ◽  
Intravascular Coagulation ◽  
Measurement Limit ◽  
Human Pathology ◽  
Rhabdophis Tigrinus

Disseminated intravascular coagulation, a severe clinical condition caused by an underlying disease, involves a markedly continuous and widespread activation of coagulation in the circulating blood and the formation of numerous microvascular thrombi. A snakebite, including that of the Yamakagashi (Rhabdophis tigrinus), demonstrates this clinical condition. Thus, an animal model using Yamakagashi venom was constructed. Yamakagashi venom was administered to rats, and its lethality and the changes in blood coagulation factors were detected after venom injection. When 300 μg venom was intramuscularly administered to 12-week-old rats, (1) they exhibited hematuria with plasma hemolysis and died within 48 h; (2) Thrombocytopenia in the blood was observed in the rats; (3) irreversible prolongation of prothrombin time in the plasma to the measurement limit occurred; (4) fibrinogen concentration in the plasma irreversibly decreased below the measurement limit; and (5) A transient increase in the plasma concentration of D-dimer was observed. In this model, a fixed amount of Rhabdophis tigrinus venom injection resulted in the clinical symptom similar to the human pathology with snakebite. The use of the rat model is very effective in validating the therapeutic effect of human disseminated intravascular coagulation condition due to snakebite.

Maternal provisioning is structured by species’ competitive neighborhoods

Oikos ◽  
2018 ◽  
Vol 128 (1) ◽  
pp. 45-53 ◽  
Author(s):  
Rachel M. Germain ◽  
Tess N. Grainger ◽  
Natalie T. Jones ◽  
Benjamin Gilbert
Keyword(s):  
Maternal Provisioning

scholarly journals Intersexual conflict over seed size is stronger in more outcrossed populations of a mixed-mating plant

2018 ◽  
Vol 115 (45) ◽  
pp. 11561-11566 ◽  
Author(s):  
Astrid Raunsgard ◽  
Øystein H. Opedal ◽  
Runa K. Ekrem ◽  
Jonathan Wright ◽  
Geir H. Bolstad ◽  
...  
Keyword(s):  
Mating Systems ◽  
Strong Support ◽  
Maternal Investment ◽  
Arms Race ◽  
Mixed Mating ◽  
Fitness Consequences ◽  
Intersexual Conflict ◽  
Maternal Provisioning ◽  
Hybrid Seeds ◽  
Parent Of Origin

In polyandrous species, fathers benefit from attracting greater maternal investment toward their offspring at the expense of the offspring of other males, while mothers should usually allocate resources equally among offspring. This conflict can lead to an evolutionary arms race between the sexes, manifested through antagonistic genes whose expression in offspring depends upon the parent of origin. The arms race may involve an increase in the strength of maternally versus paternally derived alleles engaged in a “tug of war” over maternal provisioning or repeated “recognition-avoidance” coevolution where growth-enhancing paternally derived alleles evolve to escape recognition by maternal genes targeted to suppress their effect. Here, we develop predictions to distinguish between these two mechanisms when considering crosses among populations that have reached different equilibria in this intersexual arms race. We test these predictions using crosses within and among populations ofDalechampia scandens(Euphorbiaceae) that presumably have experienced different intensities of intersexual conflict, as inferred from their historical differences in mating system. In crosses where the paternal population was more outcrossed than the maternal population, hybrid seeds were larger than those normally produced in the maternal population, whereas when the maternal population was more outcrossed, hybrid seeds were smaller than normal. These results confirm the importance of mating systems in determining the intensity of intersexual conflict over maternal investment and provide strong support for a tug-of-war mechanism operating in this conflict. They also yield clear predictions for the fitness consequences of gene flow among populations with different mating histories.

scholarly journals Molecular Signatures of Placentation and Secretion Uncovered in Poeciliopsis Maternal Follicles

2020 ◽  
Vol 37 (9) ◽  
pp. 2679-2690
Author(s):  
Michael W Guernsey ◽  
Henri van Kruistum ◽  
David N Reznick ◽  
Bart J A Pollux ◽  
Julie C Baker
Keyword(s):  
Differential Expression ◽  
Direct Contact ◽  
Molecular Level ◽  
Molecular Signatures ◽  
Maternal Circulation ◽  
The Core ◽  
Maternal Provisioning ◽  
Key Genes ◽  
Maternal Fetal Interface

Abstract Placentation evolved many times independently in vertebrates. Although the core functions of all placentas are similar, we know less about how this similarity extends to the molecular level. Here, we study Poeciliopsis, a unique genus of live-bearing fish that have independently evolved complex placental structures at least three times. The maternal follicle is a key component of these structures. It envelops yolk-rich eggs and is morphologically simple in lecithotrophic species but has elaborate villous structures in matrotrophic species. Through sequencing, the follicle transcriptome of a matrotrophic, Poeciliopsis retropinna, and lecithotrophic, P. turrubarensis, species we found genes known to be critical for placenta function expressed in both species despite their difference in complexity. Additionally, when we compare the transcriptome of different river populations of P. retropinna, known to vary in maternal provisioning, we find differential expression of secretory genes expressed specifically in the top layer of villi cells in the maternal follicle. This provides some of the first evidence that the placental structures of Poeciliopsis function using a secretory mechanism rather than direct contact with maternal circulation. Finally, when we look at the expression of placenta proteins at the maternal–fetal interface of a larger sampling of Poeciliopsis species, we find expression of key maternal and fetal placenta proteins in their cognate tissue types of all species, but follicle expression of prolactin is restricted to only matrotrophic species. Taken together, we suggest that all Poeciliopsis follicles are poised for placenta function but require expression of key genes to form secretory villi.

Sign in / Sign up

Export Citation Format

Share Document