Biology subjects

Gonzalez-Rodriguez, A.

Publications and source records attributed to Gonzalez-Rodriguez, A..

3 recordsLinked to original sources

bioRxiv2026

Seasonal blood-brain barrier plasticity links environmental cues to migratory behavior in monarch butterflies

Seasonal migration requires animals to reversibly switch behavioral states in response to environmental cues, yet the molecular and cellular mechanisms underlying these transitions remain poorly understood. Monarch butterflies provide a powerful model, as Eastern North American populations undergo a long-distance southward migration in the fall followed by a cold-dependent reversal in flight orientation after overwintering each spring. Here, we show that cold exposure induces coordinated transcriptional changes in the monarch brain, marked by attenuated integrin-mediated extracellular matrix (ECM) signaling at the blood-brain barrier (BBB). Cold-exposed monarchs exhibit increased penetration of fluorescent markers into the brain, consistent with increased BBB permeability. Notably, our findings align with previous genomic evidence identifying collagen type IV alpha 1, a major ECM component, as a locus under divergent selection between migratory and non-migratory populations. Together, these results implicate seasonal modulation of BBB permeability as a mechanism linking environmental temperature to plastic migratory behavior and identify the BBB as a dynamic interface through which seasonal cues may reprogram neural function and behavior.

neuroscience↗

bioRxiv2024

Spatiotemporal dynamics of non-ecological speciation in rubyspot damselflies (Hetaerina spp.)

Non-ecological speciation is a common mode of speciation which occurs when allopatric lineages diverge in the absence of pronounced ecological differences. Yet, relative to other speciation mechanisms, non-ecological speciation remains understudied. Numerous damselfly clades are characterized as non-adaptive radiations (the result of several rounds of non-ecological speciation), but there are few damselfly lineages for which we have a detailed understanding of the spatiotemporal dynamics of divergence. Recent phylogeographic analyses demonstrate that American rubyspot damselflies (Hetaerina americana sensu lato) actually comprise at least two cryptic lineages that coexist sympatrically across most of Mexico. To broaden our understanding of the dynamics of diversification to other rubyspot lineages, we investigated the phylogeographic history of smoky rubyspot damselflies (Hetaerina titia) using genomic data collected across Central and North America. Unexpectedly, we found evidence of reproductive isolation between the highly genetically differentiated Pacific and Atlantic lineages of H. titia in a narrow secondary contact zone on the Isthmus of Tehuantepec, Mexico. We then fit models of historical demography to both H. americana sensu lato and H. titia to place these comparisons in a temporal context. Our findings indicate that Pacific and Atlantic lineages of H. titia split more recently than the broadly sympatric lineages within H. americana sensu lato, supporting key assumptions of the non-ecological speciation model and demonstrating that these two pairs of sister lineages are at different stages of the speciation cycle.

evolutionary biology↗

bioRxiv2022

Rhamnan Sulfate Reduces Atherosclerotic Plaque Formation and Vascular Inflammation

ObjectiveWhile lipid-lowering drugs have become a mainstay of clinical therapy these treatments only slow the progression of the disease and can have side effects. Thus, new treatment options are needed to supplement the effects of lipid lowering therapy for treating atherosclerosis. We examined the use of an inexpensive and widely available marine polysaccharide rhamnan sulfate as an oral therapeutic for limiting vascular inflammation and atherosclerosis. Methods and ResultsWe found rhamnan sulfate enhanced the barrier function of endothelial cells, preventing the deposition of LDL and maintaining barrier function even in the presence of glycocalyx-degrading enzymes. Rhamnan sulfate was also found to bind directly to FGF-2, PDGF-BB and NF-{kappa}B subunits with high affinity. In addition, rhamnan sulfate was a potent inhibitor of NF-{kappa}B pathway activation in endothelial cells by TNF-. We treated ApoE-/- mice with a high fat diet for 4 weeks and then an addition 9 weeks of high fat diet with or without rhamnan sulfate. Rhamnan sulfate reduced vascular inflammation and atherosclerosis in both sexes of ApoE-/- mice but had a stronger therapeutic effect in female mice. Oral consumption of rhamnan sulfate induced a significant decrease in cholesterol plasma levels in female mice but not in male mice. ConclusionsRhamnan sulfate has beneficial effects in reducing inflammation, binding growth factors and NF-{kappa}B, enhancing endothelial barrier function and reducing atherosclerotic plaque formation in ApoE-/- mice.

physiology↗