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Temperature is a key abiotic factor that influences performance of several physiological traits in ectotherms. Organisms regulate their body temperature within a range of temperatures to enhance physiological function. The capacity of ectotherms, such as lizards, to maintain their body temperature within their preferred range influences physiological traits such as speed, various reproductive patterns, and critical fitness components, such as growth rates or survival. Here, we evaluate the influence of temperature on locomotor performance, sperm morphology and viability in a high elevation lizard species (Sceloporus aeneus). Whereas maximal values for sprint speed coincides with field active and preferred body temperature, short-term exposure at the same range of temperatures produces abnormalities in sperm morphology, lower sperm concentration and diminishes sperm motility and viability. In conclusion, we confirmed that although locomotor performance is maximized at preferred temperatures, there is a trade-off with male reproductive attributes, which may cause infertility. As a consequence, prolonged exposure to preferred temperatures could threaten the persistence of the species through reduced fertility. Persistence of the species is favored in environments with access to cooler, thermal microhabitats that enhance reproductive parameters.
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Fluorescence-Based Ratiometric Analysis of Sperm Centrioles - a method to diagnose male infertility:
A large proportion of infertility and miscarriage causes are unknown. One potential cause is a defective sperm centriole, a subcellular structure essential for sperm motility and embryonic development. Yet, the extent to which centriolar maladies contribute to male infertility is still being determined due to the lack of a convenient way to assess centriole quality. We developed a robust, location-based, ratiometric assay to overcome this roadblock, the Fluorescence-based Ratiometric Assessment of Centrioles (FRAC). We performed several pilot studies suggesting that reduced centriole quality was associated with infertility and, in particular, with unexplained infertility in humans and unexplained sub-fertility in bovines. We also found that centriole quality correlates with zygote nucleoli polarization. These findings suggest that FRAC is a sensitive method to identify unexplained infertility and potentially also miscarriage. This finding provides a rationale for a large study on the role and practical application of sperm centriole evaluation to diagnose infertility.
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- Award ID(s):
- 2233383
- PAR ID:
- 10611863
- Publisher / Repository:
- CELL BIO24
- Date Published:
- Format(s):
- Medium: X
- Institution:
- University of Toledo
- Sponsoring Org:
- National Science Foundation
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