Jasper Coty W, Molano Olivia, Fearington Forrest, Sisneros Joseph A, Coffin Allison B
Department of Integrative Physiology and Neuroscience, Washington State University Vancouver, Vancouver, WA 98686, USA.
Neuroscience Program, College of Arts and Sciences, Washington State University Vancouver, Vancouver, WA 98686, USA.
J Exp Biol. 2025 Mar 15;228(6). doi: 10.1242/jeb.250239. Epub 2025 Mar 19.
Plainfin midshipman fish (Porichthys notatus) exhibit seasonal auditory plasticity that enhances their reproductive success. During the summer, type I male midshipman acoustically court females and both the males and females exhibit increased auditory sensitivity during this period. The enhanced auditory sensitivity is associated with increased density of sensory hair cells in the saccule but not the utricle, suggesting that different mechanisms underlie physiological plasticity in distinct inner ear regions. To better understand how shifts in hair cell number occur within auditory tissues, we examined cell turnover across breeding states and sexes in midshipman fish. We found that reproductive type I males exhibited less saccular cell proliferation than non-reproductive males without a change in cell death, indicating a net loss of saccular cells during the breeding season. By contrast, saccular cell proliferation increased in summer females, with no seasonal changes in other inner ear epithelia. Collectively, our data reveal that multiple mechanisms are likely to contribute to seasonal auditory plasticity within a single species, potentially within the ear of an individual animal.
平头光尾鲨（Porichthys notatus）表现出季节性听觉可塑性，这提高了它们的繁殖成功率。在夏季，I型雄性平头光尾鲨会通过声音向雌性求爱，在此期间雄性和雌性的听觉敏感性都会增强。听觉敏感性增强与球囊中感觉毛细胞密度增加有关，而椭圆囊则没有，这表明不同的内耳区域生理可塑性的机制不同。为了更好地了解听觉组织中毛细胞数量的变化是如何发生的，我们研究了平头光尾鲨在不同繁殖状态和性别下的细胞更新情况。我们发现，繁殖期的I型雄性球囊细胞增殖比非繁殖期雄性少，而细胞死亡没有变化，这表明在繁殖季节球囊细胞出现净损失。相比之下，夏季雌性球囊细胞增殖增加，而其他内耳上皮细胞没有季节性变化。总的来说，我们的数据表明，多种机制可能导致单一物种内的季节性听觉可塑性，可能在单个动物的耳朵内起作用。
