Sarangi Navaneel, Laxme R R Senji, Sunagar Kartik
Centre for Ecological Sciences, Indian Institute of Science Bangalore, India.
PLoS Negl Trop Dis. 2025 Apr 10;19(4):e0012949. doi: 10.1371/journal.pntd.0012949. eCollection 2025 Apr.
Russell's viper (Daboia russelii) is the clinically most important snake species in the world. Considerable variation has been documented in D. russelii venoms across the Indian subcontinent, which can drive the diverse envenomation profiles in snakebite victims. Therefore, understanding the role of ecological and environmental factors influencing the compositional and functional variation can provide critical insights into the complex evolutionary adaptations of this species and pave the way for the development of targeted therapies.
We examined the influence of bioclimatic factors on D. russelii venom functions by analysing 115 samples sourced from various locations across India. The enzymatic activities of major toxins, such as proteases and phospholipases, were estimated to capture the functional variation in these venoms. Multiple regression models were developed to evaluate the relationship between venom variability and the historical climate data, specifically temperature and precipitation. Furthermore, predictive models were employed to map venom phenotypes across the distribution range of D. russelii.
Our findings reveal a collective influence of various temperature and precipitation parameters that partly explain the variability in enzymatic activities of D. russelii venom. Our models effectively captured regional differences in venom composition and linked climatic conditions with functional variations.
This study highlights the significant role of abiotic factors in shaping the venom profiles of Russell's vipers across India. The predictive venom phenotype maps developed from our models can guide the deployment of targeted therapies and treatment protocols across the biogeographically diverse Indian subcontinent and improve clinical treatment outcomes of D. russelii envenoming. This research enhances our understanding of venom phenotype evolution and has practical implications for improving snakebite management.
锯鳞蝰(Daboia russelii)是世界上临床上最重要的蛇类物种。在印度次大陆,锯鳞蝰毒液存在显著差异,这可能导致蛇咬伤受害者出现不同的中毒情况。因此,了解影响毒液成分和功能变异的生态与环境因素的作用,可为深入了解该物种复杂的进化适应性提供关键见解,并为开发针对性疗法铺平道路。
我们通过分析从印度各地采集的115份样本,研究了生物气候因素对锯鳞蝰毒液功能的影响。估算了主要毒素(如蛋白酶和磷脂酶)的酶活性,以了解这些毒液的功能变异。建立了多元回归模型,以评估毒液变异性与历史气候数据(特别是温度和降水)之间的关系。此外,还采用预测模型绘制了锯鳞蝰分布范围内的毒液表型图。
我们的研究结果揭示了各种温度和降水参数的综合影响,这些参数部分解释了锯鳞蝰毒液酶活性的变异性。我们的模型有效地捕捉到了毒液成分的区域差异,并将气候条件与功能变异联系起来。
本研究强调了非生物因素在塑造印度各地锯鳞蝰毒液特征方面的重要作用。从我们的模型中开发出的预测毒液表型图,可指导在生物地理多样的印度次大陆部署针对性疗法和治疗方案,并改善锯鳞蝰中毒的临床治疗效果。这项研究增进了我们对毒液表型进化的理解,对改善蛇咬伤管理具有实际意义。