A rapid and sensitive fluorometric method for the quantitative analysis of snake venom metalloproteases and their inhibitors

Biardi, James E.; Nguyen, Khoa T. D.; Lander, S.; Whitley, Melodi Javid; Nambiar, Krishnan P.

doi:10.1016/j.toxicon.2010.12.014

Cited by 18 publications

(19 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Phenotype matching can be identified through an analysis of local adaptation in predator venom and prey defences across populations where each coexists. Such analyses are tractable for venomous snakes and their prey through the use of well-developed in vitro tests that assess venom functional activity and prey resistance [17,18]. These functional data can then be analysed using the statistical approaches developed for assessing local adaptation in hostparasite systems [19,20].…”

Section: Introductionmentioning

confidence: 99%

Coevolution of venom function and venom resistance in a rattlesnake predator and its squirrel prey

2016

View full text Add to dashboard Cite

Measuring local adaptation can provide insights into how coevolution occurs between predators and prey. Specifically, theory predicts that local adaptation in functionally matched traits of predators and prey will not be detected when coevolution is governed by escalating arms races, whereas it will be present when coevolution occurs through an alternate mechanism of phenotype matching. Here, we analyse local adaptation in venom activity and prey resistance across 12 populations of Northern Pacific rattlesnakes and California ground squirrels, an interaction that has often been described as an arms race. Assays of venom function and squirrel resistance show substantial geographical variation (influenced by site elevation) in both venom metalloproteinase activity and resistance factor effectiveness. We demonstrate local adaptation in the effectiveness of rattlesnake venom to overcoming present squirrel resistance, suggesting that phenotype matching plays a role in the coevolution of these molecular traits. Further, the predator was the locally adapted antagonist in this interaction, arguing that rattlesnakes are evolutionarily ahead of their squirrel prey. Phenotype matching needs to be considered as an important mechanism influencing coevolution between venomous animals and resistant prey.

show abstract

Section: Introductionmentioning

confidence: 99%

Coevolution of venom function and venom resistance in a rattlesnake predator and its squirrel prey

2016

View full text Add to dashboard Cite

show abstract

“…Because they are secretions, the genotype–phenotype relationships for venoms are relatively simple, with no complicating developmental processes interposed between the expressed genes and their final products. Because of their evolutionarily critical roles in feeding and defense ( Jansa and Voss 2011 ) and antagonistic coevolutionary interactions with predators and prey ( Biardi et al 2005 , 2011 ), they appear to evolve rapidly [although exceptions are known ( Margres et al 2015a )] under diversifying selection, and regulatory changes appear to play a major role in their evolution ( Margres et al 2015a ; Rokyta et al 2015 ). Venoms are particularly significant in the context of the transcriptome–proteome relationship.…”

mentioning

confidence: 99%

Post-transcriptional Mechanisms Contribute Little to Phenotypic Variation in Snake Venoms

Rokyta

Margres

Calvin

2015

G3 Genes|Genomes|Genetics

View full text Add to dashboard Cite

Protein expression is a major link in the genotype–phenotype relationship, and processes affecting protein abundances, such as rates of transcription and translation, could contribute to phenotypic evolution if they generate heritable variation. Recent work has suggested that mRNA abundances do not accurately predict final protein abundances, which would imply that post-transcriptional regulatory processes contribute significantly to phenotypes. Post-transcriptional processes also appear to buffer changes in transcriptional patterns as species diverge, suggesting that the transcriptional changes have little or no effect on the phenotypes undergoing study. We tested for concordance between mRNA and protein expression levels in snake venoms by means of mRNA-seq and quantitative mass spectrometry for 11 snakes representing 10 species, six genera, and three families. In contrast to most previous work, we found high correlations between venom gland transcriptomes and venom proteomes for 10 of our 11 comparisons. We tested for protein-level buffering of transcriptional changes during species divergence by comparing the difference between transcript abundance and protein abundance for three pairs of species and one intraspecific pair. We found no evidence for buffering during divergence of our three species pairs but did find evidence for protein-level buffering for our single intraspecific comparison, suggesting that buffering, if present, was a transient phenomenon in venom divergence. Our results demonstrated that post-transcriptional mechanisms did not contribute significantly to phenotypic evolution in venoms and suggest a more prominent and direct role for cis-regulatory evolution in phenotypic variation, particularly for snake venoms.

show abstract

“…We used serum inhibition assays, as described elsewhere [ 57 , 97 ], to quantify serum-based resistance to SVMP activity in 18 different ground squirrel individuals. Briefly, we measured the gelatinase enzymatic activity of venom collected from sympatric Blue Oaks Ranch Reserve rattlesnakes ( C. o. oreganus; 5 individuals) using the EnzChek Gelatinase/Collagenase Assay Kit (Life Technologies, Carlsbad, CA, USA).…”

Section: Methodsmentioning

confidence: 99%

Physiological Stress Integrates Resistance to Rattlesnake Venom and the Onset of Risky Foraging in California Ground Squirrels

Holding

Putman

Kong

et al. 2020

Toxins

View full text Add to dashboard Cite

Using venom for predation often leads to the evolution of resistance in prey. Understanding individual variation in venom resistance is key to unlocking basic mechanisms by which antagonistic coevolution can sustain variation in traits under selection. For prey, the opposing challenges of predator avoidance and resource acquisition often lead to correlated levels of risk and reward, which in turn can favor suites of integrated morphological, physiological and behavioral traits. We investigate the relationship between risk-sensitive behaviors, physiological resistance to rattlesnake venom, and stress in a population of California ground squirrels. For the same individuals, we quantified foraging decisions in the presence of snake predators, fecal corticosterone metabolites (a measure of “stress”), and blood serum inhibition of venom enzymatic activity (a measure of venom resistance). Individual responses to snakes were repeatable for three measures of risk-sensitive behavior, indicating that some individuals were consistently risk-averse whereas others were risk tolerant. Venom resistance was lower in squirrels with higher glucocorticoid levels and poorer body condition. Whereas resistance failed to predict proximity to and interactions with snake predators, individuals with higher glucocorticoid levels and in lower body condition waited the longest to feed when near a snake. We compared alternative structural equation models to evaluate alternative hypotheses for the relationships among stress, venom resistance, and behavior. We found support for stress as a shared physiological correlate that independently lowers venom resistance and leads to squirrels that wait longer to feed in the presence of a snake, whereas we did not find evidence that resistance directly facilitates latency to forage. Our findings suggest that stress may help less-resistant squirrels avoid a deadly snakebite, but also reduces feeding opportunities. The combined lethal and non-lethal effects of stressors in predator–prey interactions simultaneously impact multiple key traits in this system, making environmental stress a potential contributor to geographic variation in trait expression of toxic predators and resistant prey.

show abstract

A rapid and sensitive fluorometric method for the quantitative analysis of snake venom metalloproteases and their inhibitors

Cited by 18 publications

References 28 publications

Coevolution of venom function and venom resistance in a rattlesnake predator and its squirrel prey

Coevolution of venom function and venom resistance in a rattlesnake predator and its squirrel prey

Post-transcriptional Mechanisms Contribute Little to Phenotypic Variation in Snake Venoms

Physiological Stress Integrates Resistance to Rattlesnake Venom and the Onset of Risky Foraging in California Ground Squirrels

Contact Info

Product

Resources

About