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Michael Eisenbach - One of the best experts on this subject based on the ideXlab platform.
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rhodopsin and melanopsin coexist in mammalian sperm cells and activate different signaling pathways for Thermotaxis
2020Co-Authors: Debarun Roy, Kohava Levi, Vladimir Kiss, Reinat Nevo, Michael EisenbachAbstract:Recently, various opsin types, known to be involved in vision, were demonstrated to be present in human and mouse sperm cells and to be involved there in thermosensing for Thermotaxis. In vision, each opsin type is restricted to specific cells. The situation in this respect in sperm cells is not known. It is also not known whether or not both signaling pathways, found to function in sperm Thermotaxis, are each activated by specific opsins, as in vision. Here we addressed these questions. Choosing rhodopsin and melanopsin as test cases and employing immunocytochemical analysis with antibodies against these opsins, we found that the majority of sperm cells were stained by both antibodies, indicating that most of the cells contained both opsins. By employing mutant mouse sperm cells that do not express melanopsin combined with specific signaling inhibitors, we furthermore demonstrated that rhodopsin and melanopsin each activates a different pathway. Thus, in mammalian sperm Thermotaxis, as in vision, rhodopsin and melanopsin each triggers a different signaling pathway but, unlike in vision, both opsin types coexist in the same sperm cells.
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ORIGINAL ARTICLE Reproductive biology Behavioral
2016Co-Authors: Sergii Boryshpolets, Michael EisenbachAbstract:mechanism of human sperm in Thermotaxis: a role for hyperactivatio
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involvement of opsins in mammalian sperm Thermotaxis
2015Co-Authors: Serafin Perezcerezales, Sergii Boryshpolets, Vladimir Kiss, Reinat Nevo, Oshri Afanzar, Alexander Brandis, Michael EisenbachAbstract:A unique characteristic of mammalian sperm Thermotaxis is extreme temperature sensitivity, manifested by the capacity of spermatozoa to respond to temperature changes of <0.0006 °C as they swim their body-length distance. The identity of the sensing system that confers this exceptional sensitivity on spermatozoa is not known. Here we show that the temperature-sensing system of mammalian spermatozoa involves opsins, known to be G-protein-coupled receptors that act as photosensors in vision. We demonstrate by molecular, immunological, and functional approaches that opsins are present in human and mouse spermatozoa at specific sites, which depend on the species and the opsin type, and that they are involved in sperm Thermotaxis via two signalling pathways-the phospholipase C and the cyclic-nucleotide pathways. Our results suggest that, depending on the context and the tissue, mammalian opsins act not only as photosensors but also as thermosensors.
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Behavioral mechanisms of mammalian sperm guidance
2015Co-Authors: Serafín Pérez Cerezales, Sergii Boryshpolets, Michael EisenbachAbstract:In mammals, sperm guidance in the oviduct appears essential for successful sperm arrival at the oocyte. Hitherto, three different potential sperm guidance mechanisms have been recognized: Thermotaxis, rheotaxis, and chemotaxis, each of them using specific stimuli - a temperature gradient, fluid flow, and a chemoattractant gradient, respectively. Here, we review sperm behavioral in these mechanisms and indicate commonalities and differences between them
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Thermotaxis of human sperm cells in extraordinarily shallow temperature gradients over a wide range
2012Co-Authors: Anat Bahat, Roy S Caplan, Michael EisenbachAbstract:On the basis of the finding that capacitated (ready to fertilize) rabbit and human spermatozoa swim towards warmer temperatures by directing their movement along a temperature gradient, sperm Thermotaxis has been proposed to be one of the processes guiding these spermatozoa to the fertilization site. Although the molecular mechanism underlying sperm Thermotaxis is gradually being revealed, basic questions related to this process are still open. Here, employing human spermatozoa, we addressed the questions of how wide the temperature range of Thermotaxis is, whether this range includes an optimal temperature or whether spermatozoa generally prefer swimming towards warmer temperatures, whether or not they can sense and respond to descending temperature gradients, and what the minimal temperature gradient is to which they can thermotactically respond. We found that human spermatozoa can respond thermotactically within a wide temperature range (at least 29–41°C), that within this range they preferentially accumulate in warmer temperatures rather than at a single specific, preferred temperature, that they can respond to both ascending and descending temperature gradients, and that they can sense and thermotactically respond to temperature gradients as low as <0.014°C/mm. This temperature gradient is astonishingly low because it means that as a spermatozoon swims through its entire body length (46 µm) it can sense and respond to a temperature difference of <0.0006°C. The significance of this surprisingly high temperature sensitivity is discussed.
Ikue Mori - One of the best experts on this subject based on the ideXlab platform.
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lactobacilli in a clade ameliorate age dependent decline of Thermotaxis behavior in caenorhabditis elegans
2020Co-Authors: Satoshi Higurashi, Ikue Mori, Shunji Nakano, Sachio Tsukada, Kentaro NomaAbstract:Abstract Diet is proposed to affect brain aging. However, the causality and mechanism of dietary effects on brain aging are still unclear due to the long time scales of aging. The nematode Caenorhabditis elegans (C. elegans) has led aging research because of its short lifespan and easy genetic manipulation. When fed the standard laboratory diet, Escherichia coli (E. coli), C. elegans experiences an age-dependent decline in temperature-food associative learning, called Thermotaxis. To address if diet ameliorates this decline, we screened 35 different lactic acid bacteria as alternative diets. We found that Lactobacilli in a clade enriched with heterofermentative bacteria ameliorated age-dependent decline. On the other hand, homofermentative Lactobacillus species did not show this beneficial effect. Lactobacilli affected the Thermotaxis of aged animals through DAF-16, an ortholog of mammalian FOXO transcription factor, while the effect on the Thermotaxis was independent of the lifespan and locomotion. Our results demonstrate that diet can impact brain aging without changing the lifespan and that bacterial screen using C. elegans is a powerful approach to investigate age-dependent behavioral decline.
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the caenorhabditis elegans inx 4 innexin is required for the fine tuning of temperature orientation in Thermotaxis behavior
2020Co-Authors: Satomi Tsukamoto, Taishi Emmei, Shunji Nakano, Nana Nishio, Hiroyuki Sasakura, Ikue MoriAbstract:Innexins in invertebrates are considered to play roles similar to those of connexins and pannexins in vertebrates. However, it remains poorly understood how innexins function in biological phenomena including their function in the nervous systems. Here, we identified inx-4, a member of the innexin family in C. elegans, by a forward screening of Thermotaxis-defective mutants. The inx-4 mutants exhibited abnormal migration to a temperature slightly higher than the cultivation temperature, called mild thermophilic behavior. Rescue experiments revealed that INX-4 acts in the major thermosensory neuron AFD to regulate Thermotaxis behavior. INX-4::GFP fusion protein localized exclusively along axons in AFD neurons. In addition, over-expression of INX-4 in AFD neurons induced a cryophilic behavior, which is opposite to inx-4 mutants. Our findings suggest that INX-4/Innexin in AFD may fine-tune the execution of Thermotaxis behavior when moving to desired temperatures.
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Inverse reinforcement learning analyses of ASI-, AWC-, and AFD-neuron deficient worms and starved worms.
2018Co-Authors: Shoichiro Yamaguchi, Ikue Mori, Shunji Nakano, Honda Naoki, Muneki Ikeda, Yuki Tsukada, Shin IshiiAbstract:Temporal changes in distributions of ASI-, AWC-, and AFD-neuron deficient worms, as well as of starved worms in the 17°C-, 20°C- and 23°C-centered thermal gradients after behavior onset are presented in column a of A, B, C, and D, respectively. The corresponding desirability functions are shown in column b of A, B, C, and D, respectively. Starved worms disperse under a thermal gradient, while ASI- and AWC-deficient worms migrate to the cultivation temperature, similarly to fed WT worms; AFD-deficient worms show cryophilic Thermotaxis.
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Thermotaxis navigation behavior
2014Co-Authors: Miriam B Goodman, Linjiao Luo, Ikue Mori, Mason Klein, Piali Sengupta, Samuel Lasse, Aravi Samuel, Dong WangAbstract:This chapter describes four different protocols used to assay Thermotaxis navigation behavior of single, or populations of, C. elegans hermaphrodites on spatial thermal gradients within the physiological temperature range (15-25°C). A method to assay avoidance of noxious temperatures is also described.
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Thermotaxis of c elegans as a model for temperature perception neural information processing and neural plasticity
2012Co-Authors: Tsubasa Kimata, Hiroyuki Sasakura, Nana Nishio, Noriyuki Ohnishi, Ikue MoriAbstract:Thermotaxis is a model to elucidate how nervous systems sense and memorize environmental conditions to regulate behavioral strategies in Caenorhabditis elegans. The genetic and neural imaging analyses revealed molecular and cellular bases of this experience-dependent behavior. Surprisingly, thermosensory neurons themselves memorize the sensed temperatures. Recently developed techniques for optical manipulation of neuronal activity have facilitated the revelation that there is a sophisticated information flow between sensory neurons and interneurons. Further studies on Thermotaxis will allow us to understand the fundamental logics of neural processing from sensory perceptions to behavioral outputs.
Dayong Wang - One of the best experts on this subject based on the ideXlab platform.
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serotonin control of Thermotaxis memory behavior in nematode caenorhabditis elegans
2013Co-Authors: Yunli Zhao, Xu Huang, Xingfeng Lin, Yuling Guo, Daoyong Wang, Dayong WangAbstract:Caenorhabditis elegans is as an ideal model system for the study of mechanisms underlying learning and memory. In the present study, we employed C. elegans assay system of Thermotaxis memory to investigate the possible role of serotonin neurotransmitter in memory control. Our data showed that both mutations of tph-1, bas-1, and cat-4 genes, required for serotonin synthesis, and mutations of mod-5 gene, encoding a serotonin reuptake transporter, resulted in deficits in Thermotaxis memory behavior. Exogenous treatment with serotonin effectively recovered the deficits in Thermotaxis memory of tph-1 and bas-1 mutants to the level of wild-type N2. Neuron-specific activity assay of TPH-1 suggests that serotonin might regulate the Thermotaxis memory behavior by release from the ADF sensory neurons. Ablation of ADF sensory neurons by expressing a cell-death activator gene egl-1 decreased the Thermotaxis memory, whereas activation of ADF neurons by expression of a constitutively active protein kinase C homologue (pkc-1(gf)) increased the Thermotaxis memory and rescued the deficits in Thermotaxis memory in tph-1 mutants. Moreover, serotonin released from the ADF sensory neurons might act through the G-protein-coupled serotonin receptors of SER-4 and SER-7 to regulate the Thermotaxis memory behavior. Genetic analysis implies that serotonin might further target the insulin signaling pathway to regulate the Thermotaxis memory behavior. Thus, our results suggest the possible crucial role of serotonin and ADF sensory neurons in Thermotaxis memory control in C. elegans.
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high concentration of vitamin e decreases thermosensation and Thermotaxis learning and the underlying mechanisms in the nematode caenorhabditis elegans
2013Co-Authors: Lingmei Sun, Dayong WangAbstract:α-tocopherol is a powerful liposoluble antioxidant and the most abundant isoform of vitamin E in the body. Under normal physiological conditions, adverse effects of relatively high concentration of vitamin E on organisms and the underlying mechanisms are still largely unclear. In the present study, we used the nematode Caenorhabditis elegans as an in vivo assay system to investigate the possible adverse effects of high concentration of vitamin E on thermosensation and Thermotaxis learning and the underlying mechanisms. Our data show that treatment with 100–200 µg/mL of vitamin E did not noticeably influence both thermosensation and Thermotaxis learning; however, treatment with 400 µg/mL of vitamin E altered both thermosensation and Thermotaxis learning. The observed decrease in Thermotaxis learning in 400 µg/mL of vitamin E treated nematodes might be partially due to the moderate but significant deficits in thermosensation, but not due to deficits in locomotion behavior or perception to food and starvation. Treatment with 400 µg/mL of vitamin E did not noticeably influence the morphology of GABAergic neurons, but significantly decreased fluorescent intensities of the cell bodies in AFD sensory neurons and AIY interneurons, required for thermosensation and Thermotaxis learning control. Treatment with 400 µg/mL of vitamin E affected presynaptic function of neurons, but had no remarkable effects on postsynaptic function. Moreover, promotion of synaptic transmission by activating PKC-1 effectively retrieved deficits in both thermosensation and Thermotaxis learning induced by 400 µg/mL of vitamin E. Therefore, relatively high concentrations of vitamin E administration may cause adverse effects on thermosensation and Thermotaxis learning by inducing damage on the development of specific neurons and presynaptic function under normal physiological conditions in C. elegans.
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Effects of exogenous serotonin and dopamine on Thermotaxis memory behavior in tph-1 or bas-1 mutants.
2013Co-Authors: Yunli Zhao, Xu Huang, Xingfeng Lin, Yuling Guo, Daoyong Wang, Dayong WangAbstract:(A–B) Effects of exogenous serotonin on Thermotaxis memory behavior in tph-1 mutants. (C–D) Effects of exogenous serotonin on Thermotaxis memory behavior in bas-1 mutants. (E–F) Effects of exogenous dopamine on Thermotaxis memory behavior in bas-1 mutants. Serotonin or dopamine was dissolved in M9 buffer and spread on the NGM plates at a final concentration of 2 mM or 5 mM. The normalized isothermal tracking behavior (IT) values were used. 5-HT, serotonin; DA, dopamine. Bars represent means ± S.E.M. *p
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Genetic interaction of tph-1 with insulin signals in regulating Thermotaxis memory.
2013Co-Authors: Yunli Zhao, Xu Huang, Xingfeng Lin, Yuling Guo, Daoyong Wang, Dayong WangAbstract:(A–B) Genetic interaction of tph-1 with daf-16 in regulating Thermotaxis memory. (C–D) Genetic interaction of tph-1 with daf-2 in regulating Thermotaxis memory. The normalized isothermal tracking behavior (IT) values were used. Bars represent means ± S.E.M.
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evaluation of the long term memory for thermosensation regulated by neuronal calcium sensor 1 in caenorhabditis elegans
2008Co-Authors: Dayong WangAbstract:Objective To evaluate whether the Thermotaxis tracking model is suitable for assessing long-term memory (LTM) in the nematode Caenorhabditis elegans.
Leslie B Vosshall - One of the best experts on this subject based on the ideXlab platform.
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the cation channel trpa1 tunes mosquito Thermotaxis to host temperatures
2015Co-Authors: Roman A Corfas, Leslie B VosshallAbstract:While most animals thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti Thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cool and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective Thermotaxis in mosquitoes. During host-seeking, AaegTRPA1(-/-) mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of Thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.
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trpa1 tunes mosquito Thermotaxis to host temperatures
2015Co-Authors: Roman A Corfas, Leslie B VosshallAbstract:While most ectotherms thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti Thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cooling and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective Thermotaxis in mosquitoes. During host-seeking, AaegTRPA1-/- mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of Thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.
Anat Bahat - One of the best experts on this subject based on the ideXlab platform.
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Thermotaxis of human sperm cells in extraordinarily shallow temperature gradients over a wide range
2012Co-Authors: Anat Bahat, Roy S Caplan, Michael EisenbachAbstract:On the basis of the finding that capacitated (ready to fertilize) rabbit and human spermatozoa swim towards warmer temperatures by directing their movement along a temperature gradient, sperm Thermotaxis has been proposed to be one of the processes guiding these spermatozoa to the fertilization site. Although the molecular mechanism underlying sperm Thermotaxis is gradually being revealed, basic questions related to this process are still open. Here, employing human spermatozoa, we addressed the questions of how wide the temperature range of Thermotaxis is, whether this range includes an optimal temperature or whether spermatozoa generally prefer swimming towards warmer temperatures, whether or not they can sense and respond to descending temperature gradients, and what the minimal temperature gradient is to which they can thermotactically respond. We found that human spermatozoa can respond thermotactically within a wide temperature range (at least 29–41°C), that within this range they preferentially accumulate in warmer temperatures rather than at a single specific, preferred temperature, that they can respond to both ascending and descending temperature gradients, and that they can sense and thermotactically respond to temperature gradients as low as <0.014°C/mm. This temperature gradient is astonishingly low because it means that as a spermatozoon swims through its entire body length (46 µm) it can sense and respond to a temperature difference of <0.0006°C. The significance of this surprisingly high temperature sensitivity is discussed.
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human sperm Thermotaxis is mediated by phospholipase c and inositol trisphosphate receptor ca2 channel
2010Co-Authors: Anat Bahat, Michael EisenbachAbstract:Capacitated human and rabbit spermatozoa can sense temperature differences as small as those within the oviduct of rabbits and pigs at ovulation, and they respond to them by Thermotaxis (i.e., by swimming from the cooler to the warmer temperature). The molecular mechanism of sperm Thermotaxis is obscure. To reveal molecular events involved in sperm Thermotaxis, we took a pharmacological approach in which we examined the effect of different inhibitors and blockers on the thermotactic response of human spermatozoa. We found that reducing the intracellular, but not extracellular, Ca 2+ concentration caused remarkable inhibition of the thermotactic response. The thermotactic response was also inhibited by each of the following: La 3+ , a general blocker of Ca 2+ channels; U73122, an inhibitor of phospholipase C (PLC); and 2-aminoethoxy diphenyl borate, an inhibitor of inositol 1,4,5-trisphosphate receptors (IP 3 R) and store-operated channels. Inhibitors and blockers of other channels had no effect. Likewise, saturating concentrations of the chemoattractants for the known chemotaxis receptors had no effect on the thermotactic response. The results suggest that the IP 3 RC a 2+ channel, located on internal Ca 2+ stores, operates in sperm Thermotaxis, and that the response is mediated by PLC and requires intracellular Ca 2+ . They also suggest that the thermosensors for Thermotaxis are not the currently known chemotaxis receptors. sperm chemotaxis motility and transport, sperm Thermotaxis
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human sperm Thermotaxis is mediated by phospholipase c and inositol trisphosphate receptor ca 2 channel short title sperm Thermotaxis mediated by plc and ip3r summary sentence the ip3r ca 2 channel located on internal ca 2 stores operates in human sperm Thermotaxis and the response is mediated by plc and requires intracellular ca 2
2009Co-Authors: Anat Bahat, Michael EisenbachAbstract:Capacitated human and rabbit spermatozoa can sense temperature differences as small as those within the oviduct of rabbits and pigs at ovulation, and respond to them by Thermotaxis, i.e., by swimming from the cooler to the warmer temperature. The molecular mechanism of sperm Thermotaxis is obscure. To reveal molecular events involved in sperm Thermotaxis we took a pharmacological approach in which we examined the effect of different inhibitors and blockers on the thermotactic response of human spermatozoa. We found that reducing the intracellular, but not extracellular, Ca 2+ concentration caused remarkable inhibition of the thermotactic response. The thermotactic response was also inhibited by each of the following: La 3+ — a general blocker of Ca 2+ channels, U73122 — an inhibitor of phospholipase C (PLC), and 2aminoethoxy diphenylborate — an inhibitor of inositol 1,4,5-trisphosphate receptors (IP3R) and store-operated channels. Inhibitors and blockers of other channels had no effect. Likewise, saturating concentrations of the chemoattractants for the known chemotaxis receptors had no effect on the thermotactic response. The results suggest that the IP3R Ca 2+ channel, located on internal Ca 2+ stores, operates in sperm Thermotaxis, and that the response is mediated by PLC and requires intracellular Ca 2+ . They also suggest that the thermosensors for Thermotaxis are not
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Thermotaxis of mammalian sperm cells a potential navigation mechanism in the female genital tract
2003Co-Authors: Anat Bahat, Ilan Turkaspa, Anna Gakamsky, Laura Cecilia Giojalas, Haim Breitbart, Michael EisenbachAbstract:Thermotaxis of mammalian sperm cells: A potential navigation mechanism in the female genital tract
