Armenta Tiffany C, Cole Steve W, Geschwind Daniel H, Blumstein Daniel T, Wayne Robert K
Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, CA, USA.
Rocky Mountain Biological Laboratory, Crested Butte, CO, USA.
Behav Ecol. 2019 Mar-Apr;30(2):267-277. doi: 10.1093/beheco/ary175. Epub 2018 Dec 17.
The causes and consequences of vertebrate natal dispersal have been studied extensively, yet little is known about the molecular mechanisms involved. We used RNA-seq to quantify transcriptomic gene expression in blood of wild yellow-bellied marmots () prior to dispersing from or remaining philopatric to their natal colony. We tested 3 predictions. First, we hypothesized dispersers and residents will differentially express genes and gene networks since dispersal is physiologically demanding. Second, we expected differentially expressed genes to be involved in metabolism, circadian processes, and immune function. Finally, in dispersing individuals, we predicted differentially expressed genes would change as a function of sampling date relative to dispersal date. We detected 150 differentially expressed genes, including genes that have critical roles in lipid metabolism and antigen defense. Gene network analysis revealed a module of 126 coexpressed genes associated with dispersal that was enriched for extracellular immune function. Of the dispersal-associated genes, 22 altered expression as a function of days until dispersal, suggesting that dispersal-associated genes do not initiate transcription on the same time scale. Our results provide novel insights into the fundamental molecular changes required for dispersal and suggest evolutionary conservation of functional pathways during this behavioral process.
脊椎动物出生后扩散的原因和后果已得到广泛研究，但对其中涉及的分子机制却知之甚少。我们使用RNA测序来量化野生黄腹旱獭（Marmota flaviventris）在从其出生群体扩散或留居之前血液中的转录组基因表达。我们测试了3个预测。首先，我们假设扩散个体和留居个体将差异表达基因和基因网络，因为扩散对生理要求很高。其次，我们预期差异表达基因会参与代谢、昼夜节律过程和免疫功能。最后，对于扩散个体，我们预测差异表达基因会随着相对于扩散日期的采样日期而变化。我们检测到150个差异表达基因，包括在脂质代谢和抗原防御中起关键作用的基因。基因网络分析揭示了一个由126个与扩散相关的共表达基因组成的模块，该模块在细胞外免疫功能方面富集。在与扩散相关的基因中，有22个基因的表达随着距离扩散的天数而变化，这表明与扩散相关的基因并非在同一时间尺度上启动转录。我们的结果为扩散所需的基本分子变化提供了新的见解，并表明在这一行为过程中功能途径的进化保守性。
