Biology subjects

Mason, A. C.

Publications and source records attributed to Mason, A. C..

4 recordsLinked to original sources

bioRxiv2026

Multidimensional encoding of temporal features underlies song recognition in Floridian Ormia ochracea

Acoustic communication signals often contain complex temporal structure, yet the features underlying signal recognition remain poorly understood, particularly in eavesdropping receivers. The parasitoid fly Ormia ochracea localises host crickets by eavesdropping on their calling songs. In Florida, preferred host songs consist of sound pulses repeated at ~50 pulses/s, and flies exhibit matching preferences. However, it remains unclear whether this preference reflects sensitivity to individual temporal features (e.g., pulse duration, interpulse interval) or to derived temporal relationships (e.g., pulse rate, pulse period, duty cycle) that emerge from their combination. We independently varied pulse duration and interpulse interval across a broad stimulus space and quantified tethered-walking phonotaxis using a switch-following paradigm. Behavioural responses formed a structured tuning surface, with high performance along a diagonal corresponding to 50 pulses/s, as well as elevated responses for a restricted range of pulse durations across a wide range of interpulse intervals. Responses failed to collapse across stimuli sharing the same pulse rate or pulse period, indicating that these features alone do not determine recognition. Instead, behaviour was best explained by the interacting effects of pulse duration and interpulse interval. These results demonstrate that song recognition in O. ochracea is multidimensional, with pulse rate tuning emerging from an underlying feature space rather than a single encoded parameter.

animal behavior and cognition↗

bioRxiv2024

Resource competition affects the developmental outcome of the acoustic parasitoid fly Ormia ochracea

Ormia ochracea is an acoustic parasitoid fly where the adults are free-living, but their larval young depend on nutritional resources within host crickets for growth and development. In nature, gravid female flies rely on their ability to recognize and localize cricket calling songs to find suitable host species to parasitize. In depth investigations of fly behavior and the mechanistic bases of auditory perception require a reliable approach to propagate stable fly colonies in the laboratory. Previous work has demonstrated that flies can be propagated using a number of natural host cricket species, as well as cricket species that flies do not parasitize in nature. However, we lack a complete understanding of fly developmental outcomes when non-host cricket species are utilized to propagate fly colonies. In this study, we document the feasibility of using commercially supplied Acheta domesticus as a host species. We specifically test the hypothesis that host size and resource competition can affect developmental outcomes of O. ochracea. We performed manual parasitizations on crickets that varied in size, and resource competition was varied by manipulating the number of larvae used to parasitize a host cricket. A series of morphometric analyses were conducted on host crickets, and developmental outcomes were measured in terms of pupation success and eclosion success, pupal width, and eclosed adult fly size. In the absence of resource competition, we found that host cricket size did not affect pupation or eclosion success. In the presence of resource competition between two developing larvae within a host cricket, pupation and eclosion successes were impacted negatively, and the developing pupae were more likely to be smaller. These results confirm that resource competition among developing parasitoids can negatively affect developmental outcomes, and Acheta domesticus can be used effectively to propagate colonies of O. ochracea in the laboratory. HighlightsO_LIThe acoustic parasitoid fly Ormia ochracea can successfully develop within the house cricket Acheta domesticus. C_LIO_LIPupal size and eclosed adult fly size varies positively with the size of host cricket. C_LIO_LIResource competition negatively affects pupation and eclosion success. C_LIO_LIResource competition resulted in smaller fly pupae that were less likely to eclose. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=192 HEIGHT=200 SRC="FIGDIR/small/590943v1_ufig1.gif" ALT="Figure 1"> View larger version (40K): org.highwire.dtl.DTLVardef@b86e19org.highwire.dtl.DTLVardef@44444corg.highwire.dtl.DTLVardef@1dfe813org.highwire.dtl.DTLVardef@fd5b3b_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

bioRxiv2020

Functions of Gle1 are governed by two distinct modes of self-association

Gle1 is a conserved, essential regulator of DEAD-box RNA helicases, with critical roles defined in mRNA export, translation initiation, translation termination, and stress granule formation. Mechanisms that specify which, where and when DDXs are targeted by Gle1 are critical to understand. In addition to roles for stress-induced phosphorylation and inositol hexakisphosphate (IP6) binding in specifying Gle1 function, Gle1 oligomerizes via its N-terminal domain in a phosphorylation-dependent manner. However, a thorough analysis of the role for Gle1 self-association is lacking. Here, we find that Gle1 self-association is driven by two distinct regions: a coiled-coil domain and a novel ten amino acid aggregation prone region, both of which are necessary for proper Gle1 oligomerization. By exogenous expression in HeLa cells, we tested the function of a series of mutations that impact the oligomerization domains of the Gle1A and Gle1B isoforms. Gle1 oligomerization is necessary for many, but not all aspects of Gle1A and Gle1B function, and the requirements for each interaction domain differ. Whereas the coiled-coil domain and aggregation prone region additively contribute to competent mRNA export and stress granule formation, both self-association domains are independently required for regulation of translation under cellular stress. In contrast, Gle1 self-association is dispensable for phosphorylation and non-stressed translation initiation. Collectively, we reveal self-association functions as an additional mode of Gle1 regulation to ensure proper mRNA export and translation. This work also provides further insight into the mechanisms underlying human gle1 disease mutants found in prenatally lethal forms of arthrogryposis.

cell biology↗

bioRxiv2018

Posture controls mechanical tuning in the black widow spider mechanosensory system

Spiders rely on mechanical vibration sensing for sexual signalling, prey capture and predator evasion. The sensory organs underlying vibration detection, called slit sensilla, resemble cracks in the spiders exoskeleton, and are distributed all over the spider body. Those crucial to sensing web- and other substrate-borne vibrations are called lyriform organs and are densely distributed around leg joints. It has been shown that forces that cause bending at leg joints also activate these lyriform organs. Little is known of how the biomechanics of the body of a freely-suspended spider in its natural posture interact with vibrations introduced into the body and how this affects vibration perception. Female black widow spiders, in particular, have a striking body-form; their long thin legs support a large pendulous abdomen. Here, we show that in their natural posture, the large abdominal mass of black widow females, interacts with the spring-like behaviour of their leg joints and determines the mechanical behaviour of different leg joints. Furthermore, we find that adopting different body postures enables females to alter both the level and tuning of the mechanical input to lyriform organs. Therefore, we suggest that posture may be used to flexibly and reversibly focus attention to different classes or components of web vibration. Postural effects thus emphasize the dynamic loop of interactions between behaviour and perception, i.e. between brain and body.

animal behavior and cognition↗