Sex Role–Dependent Behavioral and Architectural Divergence in a Jumping Spider

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  Sex Role–Dependent Behavioral and Architectural Divergence in a Jumping Spider ABSTRACT Sex differences in behavior and functional traits are often attributed to differences in mating effort intensity, but the role of sex-specific parental demands remains poorly understood. Using the jumping spider Toxeus maxillosus —where males engage in mate searching and courtship without providing parental care, while females provide extended maternal care from egg attendance to offspring maturity (around 3 months)—we conducted an exploratory investigation into whether these distinct selective pressures led to divergence in spatial behaviors and nest architecture. Results revealed that males and females showed equivalent accuracy, latency, and learning-related performance in both a route-planning test under water stress and a color-pattern associative memory task. In contrast, during nest-construction assays, females built complex, multi-entrance structures that closely matched the container'...

The protamines of the spider Steatoda sp. provide an example of liquid-liquid phase separation chromatin transitions during spermiogenesis

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The protamines of the spider Steatoda sp. provide an example of liquid-liquid phase separation chromatin transitions during spermiogenesis

While there is extensive information about sperm nuclear basic proteins (SNBP) in vertebrates, there is by comparison, very little information in Arthropoda. This paper aims to contribute to filling this gap by analyzing these proteins in the sperm of the noble false widow spider Steatoda nobilis (Order Araneae, Family Theridiidae). To this end, we have developed a protein extraction method that allows the extraction of both cysteine-containing and non-Cysteine-containing protamines that is suitable for the preparation and analysis of SNBPs from samples where the amount of starting tissue material is limited. We carried out top-down mass spectrometry sequencing and molecular phylogenetic analyses to characterize the protamines of S. nobilis and other spiders. We also used electron microscopy to analyse the chromatin organization of the Steatoda sperm and we found it to exhibit liquid-liquid phase spinodal decomposition during the late stages of spermiogenesis. These studies further our knowledge on the distribution of SNBPs within the animal kingdom and provide additional support for a proposed evolutionary origin of many protamines from a histone H1 (H5) replication independent precursor.

Melissa R. Leyden, Peter Michalik, Luciana Baruffaldi, Susheen Mahmood, Ladan Kalani, Donald F. Hunt, Jose Maria Eirin-Lopez, Maydianne C. B. Andrade, Jeffrey Shabanowitz, Juan Ausió; The protamines of the spider Steatoda sp. provide an example of liquid-liquid phase separation chromatin transitions during spermiogenesis. Development 2024; dev.203134. doi: https://doi.org/10.1242/dev.203134