scholarly journals A host beetle pheromone regulates development and behavior in the nematode Pristionchus pacificus

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Jessica K Cinkornpumin ◽  
Dona R Wisidagama ◽  
Veronika Rapoport ◽  
James L Go ◽  
Christoph Dieterich ◽  
...  
Keyword(s):  
Cell Types ◽  
Lipid Binding ◽  
Biological Interactions ◽  
Pristionchus Pacificus ◽  
Binding Domains ◽  
Animal Phyla ◽  
Oriental Beetle ◽  
Species Specific ◽  
And Behavior ◽  
Dauer Larvae

Nematodes and insects are the two most speciose animal phyla and nematode–insect associations encompass widespread biological interactions. To dissect the chemical signals and the genes mediating this association, we investigated the effect of an oriental beetle sex pheromone on the development and behavior of the nematode Pristionchus pacificus. We found that while the beetle pheromone is attractive to P. pacificus adults, the pheromone arrests embryo development, paralyzes J2 larva, and inhibits exit of dauer larvae. To uncover the mechanism that regulates insect pheromone sensitivity, a newly identified mutant, Ppa-obi-1, is used to reveal the molecular links between altered attraction towards the beetle pheromone, as well as hypersensitivity to its paralyzing effects. Ppa-obi-1 encodes lipid-binding domains and reaches its highest expression in various cell types, including the amphid neuron sheath and excretory cells. Our data suggest that the beetle host pheromone may be a species-specific volatile synomone that co-evolved with necromeny.

THE ROLE OF TRANSPOSABLE ELEMENTS IN ENDOCRINE CHANGES DURING AGING

2020 ◽  
pp. 418-428
Author(s):  
Р. Н. Мустафин ◽  
Э. К. Хуснутдинова
Keyword(s):  
Hormonal Regulation ◽  
Endocrine System ◽  
Cell Types ◽  
Key Factors ◽  
Dna Binding Domains ◽  
Binding Domains ◽  
Stage Of Development ◽  
Expression Of Genes ◽  
Transposon Activity ◽  
Species Specific

Одним из ключевых механизмов старения является изменение гормональной регуляции, для эффективного воздействия на которую с целью продления жизни необходимо определение первопричины данных процессов. В качестве молекулярных драйверов, управляющих динамикой уровня гормонов, могут служить транспозоны. Это связано с их использованием в качестве источников нуклеотидных последовательностей, воспринимающих специфические сигналы рибозимов, транскрипционных факторов, гормонов и их мессенджеров. В то же время, в эволюции транспозоны являются источниками рибозимов и белков, обладающих ДНК-связывающими доменами. Начиная с деления зиготы, видоспецифический состав и распределение транспозонов в геноме могут использоваться как биологическая кодировка, необходимая для последовательной и специфической для типов клеток экспрессии генов. Сделано предположение, что гормональная регуляция является одним из компонентов сложной системы управления онтогенезом под влиянием мобильных элементов. В качестве подтверждения приведены работы о роли транспозонов в управлении генами эндокринной системы, а также о влиянии гормонов на активность транспозонов. Исследование этих взаимосвязей может иметь перспективы для разработки методов продления жизни, так как эпигенетические изменения под влиянием транспозонов носят обратимый характер. Species-specific changes in the endocrine system are key factors in aging. Therefore, to prolong life, it is necessary to find regulators of the highest level, the changes of which lead to physiological aging. The molecular drivers that control dynamics of hormone levels can be transposons. This is due to the use of nucleotide sequences of transposons as binding sites that perceive specific signals of ribozymes, transcription factors, hormones and their messengers. At the same time, transposons are evolutionary sources of ribozymes and proteins that have DNA-binding domains. Starting from zygote division, the species-specific composition and distribution of transposons in the genome serves as a biological coding, which is necessary for the sequential expression of genes specific to cell types and stage of development. We suggest that hormonal regulation is one of the components of this complex system of regulation of ontogenesis under the control of transposons. To confirm our hypothesis, this review contains articles that prove the importance of transposons for species-specific control of endocrine system genes, as well as the effect of hormones on transposon activity. The research of these relationships is promising for the development of methods for the effective prolongation of life, since epigenetic changes under the influence of transposons are reversible.

scholarly journals Olfactory processing in the lateral horn of Drosophila

2021 ◽  
Vol 383 (1) ◽  
pp. 113-123
Author(s):  
Sudeshna Das Chakraborty ◽  
Silke Sachse
Keyword(s):  
Functional Properties ◽  
Olfactory System ◽  
Cell Types ◽  
Specific Cell ◽  
Olfactory Behavior ◽  
Lateral Horn ◽  
Behavioral Decision ◽  
Animal Phyla ◽  
Survival And Reproduction ◽  
Almost All

AbstractSensing olfactory signals in the environment represents a crucial and significant task of sensory systems in almost all organisms to facilitate survival and reproduction. Notably, the olfactory system of diverse animal phyla shares astonishingly many fundamental principles with regard to anatomical and functional properties. Binding of odor ligands by chemosensory receptors present in the olfactory peripheral organs leads to a neuronal activity that is conveyed to first and higher-order brain centers leading to a subsequent odor-guided behavioral decision. One of the key centers for integrating and processing innate olfactory behavior is the lateral horn (LH) of the protocerebrum in insects. In recent years the LH of Drosophila has garnered increasing attention and many studies have been dedicated to elucidate its circuitry. In this review we will summarize the recent advances in mapping and characterizing LH-specific cell types, their functional properties with respect to odor tuning, their neurotransmitter profiles, their connectivity to pre-synaptic and post-synaptic partner neurons as well as their impact for olfactory behavior as known so far.

scholarly journals Structural insights into the interaction of helicase and primase in Mycobacterium tuberculosis

2018 ◽  
Vol 475 (21) ◽  
pp. 3493-3509 ◽  
Author(s):  
Dhakaram Pangeni Sharma ◽  
Ramachandran Vijayan ◽  
Syed Arif Abdul Rehman ◽  
Samudrala Gourinath
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Replication Initiation ◽  
Binding Studies ◽  
Functional Conservation ◽  
Terminal Domain ◽  
Binding Domains ◽  
Initiation System ◽  
Helical Hairpin ◽  
Helicase Dnab ◽  
Species Specific

The helicase–primase interaction is an essential event in DNA replication and is mediated by the highly variable C-terminal domain of primase (DnaG) and N-terminal domain of helicase (DnaB). To understand the functional conservation despite the low sequence homology of the DnaB-binding domains of DnaGs of eubacteria, we determined the crystal structure of the helicase-binding domain of DnaG from Mycobacterium tuberculosis (MtDnaG-CTD) and did so to a resolution of 1.58 Å. We observed the overall structure of MtDnaG-CTD to consist of two subdomains, the N-terminal globular region (GR) and the C-terminal helical hairpin region (HHR), connected by a small loop. Despite differences in some of its helices, the globular region was found to have broadly similar arrangements across the species, whereas the helical hairpins showed different orientations. To gain insights into the crucial helicase–primase interaction in M. tuberculosis, a complex was modeled using the MtDnaG-CTD and MtDnaB-NTD crystal structures. Two nonconserved hydrophobic residues (Ile605 and Phe615) of MtDnaG were identified as potential key residues interacting with MtDnaB. Biosensor-binding studies showed a significant decrease in the binding affinity of MtDnaB-NTD with the Ile605Ala mutant of MtDnaG-CTD compared with native MtDnaG-CTD. The loop, connecting the two helices of the HHR, was concluded to be largely responsible for the stability of the DnaB–DnaG complex. Also, MtDnaB-NTD showed micromolar affinity with DnaG-CTDs from Escherichia coli and Helicobacter pylori and unstable binding with DnaG-CTD from Vibrio cholerae. The interacting domains of both DnaG and DnaB demonstrate the species-specific evolution of the replication initiation system.

Fish Bioacoustics and Behavior: Passive Acoustic Detection and the Application of a Closed-Circuit Rebreather for Field Study

2001 ◽  
Vol 35 (2) ◽  
pp. 19-28 ◽  
Author(s):  
Phillip S. Lobel
Keyword(s):  
Behavioral Ecology ◽  
Daily Basis ◽  
Open Circuit ◽  
Acoustic Detection ◽  
Ecological Processes ◽  
Detection Technology ◽  
Scientific Goal ◽  
Species Specific ◽  
Passive Acoustic ◽  
And Behavior

The simple thesis of this paper is that using rebreathers to study fish behavioral ecology, especially bioacoustics, is well worth the expense and additional training required. The scientific goal of my bioacoustic research is to determine which fishes produce species-specific sound patterns exclusively with explicit acts of courtship and mating. This provides scientific insight into evolutionary and ecological processes and also provides data necessary to develop the passive acoustic detection technology for monitoring fish reproduction. When used on a daily basis, rebreathers, in my experience, are economical and as practical as open circuit scuba. This is based both on the costs of diving as well as the efficiency of gathering useful data. The use of open circuit SCUBA while conducting acoustic recordings results in a loss of at least 40% of the data due to the bubble noise from a divers breathing. Rebreathers also provide extended bottom time, especially in shallow water, which enhances a diver's ability to observe fish and gather acoustic-behavioral data.

scholarly journals Mapping single-cell atlases throughout Metazoa unravels cell type evolution

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alexander J Tarashansky ◽  
Jacob M Musser ◽  
Margarita Khariton ◽  
Pengyang Li ◽  
Detlev Arendt ◽  
...  
Keyword(s):  
Stem Cell ◽  
Single Cell ◽  
Cell Types ◽  
The Self ◽  
Cell Type ◽  
Germ Layers ◽  
Animal Evolution ◽  
Self Assembling ◽  
Animal Phyla ◽  
Cell Data

Comparing single-cell transcriptomic atlases from diverse organisms can elucidate the origins of cellular diversity and assist the annotation of new cell atlases. Yet, comparison between distant relatives is hindered by complex gene histories and diversifications in expression programs. Previously, we introduced the self-assembling manifold (SAM) algorithm to robustly reconstruct manifolds from single-cell data (Tarashansky et al., 2019). Here, we build on SAM to map cell atlas manifolds across species. This new method, SAMap, identifies homologous cell types with shared expression programs across distant species within phyla, even in complex examples where homologous tissues emerge from distinct germ layers. SAMap also finds many genes with more similar expression to their paralogs than their orthologs, suggesting paralog substitution may be more common in evolution than previously appreciated. Lastly, comparing species across animal phyla, spanning mouse to sponge, reveals ancient contractile and stem cell families, which may have arisen early in animal evolution.

scholarly journals daf-16/FOXO blocks adult cell fate in Caenorhabditis elegans dauer larvae via lin-41/TRIM71

PLoS Genetics ◽  
2021 ◽  
Vol 17 (11) ◽  
pp. e1009881
Author(s):  
Matthew J. Wirick ◽  
Allison R. Cale ◽  
Isaac T. Smith ◽  
Amelia F. Alessi ◽  
Margaret R. Starostik ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Fate ◽  
Rna Binding ◽  
Cell Model ◽  
Cell Types ◽  
Adult Cell ◽  
Heterochronic Gene ◽  
Foxo Transcription Factors ◽  
Dauer Larvae

Many tissue-specific stem cells maintain the ability to produce multiple cell types during long periods of non-division, or quiescence. FOXO transcription factors promote quiescence and stem cell maintenance, but the mechanisms by which FOXO proteins promote multipotency during quiescence are still emerging. The single FOXO ortholog in C. elegans, daf-16, promotes entry into a quiescent and stress-resistant larval stage called dauer in response to adverse environmental cues. During dauer, stem and progenitor cells maintain or re-establish multipotency to allow normal development to resume after dauer. We find that during dauer, daf-16/FOXO prevents epidermal stem cells (seam cells) from prematurely adopting differentiated, adult characteristics. In particular, dauer larvae that lack daf-16 misexpress collagens that are normally adult-enriched. Using col-19p::gfp as an adult cell fate marker, we find that all major daf-16 isoforms contribute to opposing col-19p::gfp expression during dauer. By contrast, daf-16(0) larvae that undergo non-dauer development do not misexpress col-19p::gfp. Adult cell fate and the timing of col-19p::gfp expression are regulated by the heterochronic gene network, including lin-41 and lin-29. lin-41 encodes an RNA-binding protein orthologous to LIN41/TRIM71 in mammals, and lin-29 encodes a conserved zinc finger transcription factor. In non-dauer development, lin-41 opposes adult cell fate by inhibiting the translation of lin-29, which directly activates col-19 transcription and promotes adult cell fate. We find that during dauer, lin-41 blocks col-19p::gfp expression, but surprisingly, lin-29 is not required in this context. Additionally, daf-16 promotes the expression of lin-41 in dauer larvae. The col-19p::gfp misexpression phenotype observed in dauer larvae with reduced daf-16 requires the downregulation of lin-41, but does not require lin-29. Taken together, this work demonstrates a novel role for daf-16/FOXO as a heterochronic gene that promotes expression of lin-41/TRIM71 to contribute to multipotent cell fate in a quiescent stem cell model.

daf-16/FOXO blocks adult cell fate in Caenorhabditis elegans dauer larvae via lin-41/TRIM71

2021 ◽  
Author(s):  
Matthew J Wirick ◽  
Allison R Cale ◽  
Isaac T Smith ◽  
Amelia F Alessi ◽  
Margaret R Starostik ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Fate ◽  
Rna Binding ◽  
Cell Model ◽  
Cell Types ◽  
Adult Cell ◽  
Heterochronic Gene ◽  
Foxo Transcription Factors ◽  
Dauer Larvae

Many tissue-specific stem cells maintain the ability to produce multiple cell types during long periods of non-division, or quiescence. FOXO transcription factors promote quiescence and stem cell maintenance, but the mechanisms by which FOXO proteins promote multipotency during quiescence are still emerging. The single FOXO ortholog in C. elegans, daf-16, promotes entry into a quiescent and stress-resistant larval stage called dauer in response to adverse environmental cues. During dauer, stem and progenitor cells maintain or re-establish multipotency to allow normal development to resume after dauer. We find that during dauer, daf-16/FOXO prevents epidermal stem cells (seam cells) from prematurely adopting differentiated, adult characteristics. In particular, dauer larvae that lack daf-16 misexpress collagens that are normally adult-enriched. Using col-19p::gfp as an adult cell fate marker, we find that all major daf-16 isoforms contribute to opposing col-19p::gfp expression during dauer. By contrast, daf-16(0) larvae that undergo non-dauer development do not misexpress col-19p::gfp. Adult cell fate and the timing of col-19p::gfp expression are regulated by the heterochronic gene network, including lin-41 and lin-29. lin-41 encodes an RNA-binding protein orthologous to LIN41/TRIM71 in mammals, and lin-29 encodes a conserved zinc finger transcription factor. In non-dauer development lin-41 opposes adult cell fate by inhibiting the translation of lin-29, which directly activates col-19 transcription and promotes adult cell fate. We find that during dauer, lin-41 blocks col-19p::gfp expression, but surprisingly, lin-29 is not required in this context. Additionally, daf-16 promotes the expression of lin-41 in dauer larvae. The col-19p::gfp misexpression phenotype observed in dauer larvae with reduced daf-16 requires the downregulation of lin-41, but does not require lin-29. Taken together, this work demonstrates a novel role for daf-16/FOXO as a heterochronic gene that promotes expression of lin-41/TRIM71 to contribute to multipotent cell fate in a quiescent stem cell model.

scholarly journals Event-related functional MRI of awake behaving pigeons at 7T

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Mehdi Behroozi ◽  
Xavier Helluy ◽  
Felix Ströckens ◽  
Meng Gao ◽  
Roland Pusch ◽  
...  
Keyword(s):  
Functional Mri ◽  
Color Discrimination ◽  
Motion Artifacts ◽  
Stress Conditions ◽  
Neural Mechanisms ◽  
Single Shot ◽  
Visually Guided ◽  
Hemodynamic Response Function ◽  
Species Specific ◽  
And Behavior

Abstract Animal-fMRI is a powerful method to understand neural mechanisms of cognition, but it remains a major challenge to scan actively participating small animals under low-stress conditions. Here, we present an event-related functional MRI platform in awake pigeons using single-shot RARE fMRI to investigate the neural fundaments for visually-guided decision making. We established a head-fixated Go/NoGo paradigm, which the animals quickly learned under low-stress conditions. The animals were motivated by water reward and behavior was assessed by logging mandibulations during the fMRI experiment with close to zero motion artifacts over hundreds of repeats. To achieve optimal results, we characterized the species-specific hemodynamic response function. As a proof-of-principle, we run a color discrimination task and discovered differential neural networks for Go-, NoGo-, and response execution-phases. Our findings open the door to visualize the neural fundaments of perceptual and cognitive functions in birds—a vertebrate class of which some clades are cognitively on par with primates.

scholarly journals Num1 anchors mitochondria to the plasma membrane via two domains with different lipid binding specificities

2016 ◽  
Vol 213 (5) ◽  
pp. 513-524 ◽  
Author(s):  
Holly A. Ping ◽  
Lauren M. Kraft ◽  
WeiTing Chen ◽  
Amy E. Nilles ◽  
Laura L. Lackner
Keyword(s):  
Plasma Membrane ◽  
Specific Binding ◽  
Coiled Coil ◽  
Lipid Binding ◽  
General Mechanism ◽  
Cell Cortex ◽  
Pleckstrin Homology Domain ◽  
Binding Domains ◽  
Coiled Coil Domain ◽  
Mitochondrial Distribution

The mitochondria–ER cortex anchor (MECA) is required for proper mitochondrial distribution and functions by tethering mitochondria to the plasma membrane. The core component of MECA is the multidomain protein Num1, which assembles into clusters at the cell cortex. We show Num1 adopts an extended, polarized conformation. Its N-terminal coiled-coil domain (Num1CC) is proximal to mitochondria, and the C-terminal pleckstrin homology domain is associated with the plasma membrane. We find that Num1CC interacts directly with phospholipid membranes and displays a strong preference for the mitochondria-specific phospholipid cardiolipin. This direct membrane interaction is critical for MECA function. Thus, mitochondrial anchoring is mediated by a protein that interacts directly with two different membranes through lipid-specific binding domains, suggesting a general mechanism for interorganelle tethering.

Lipid Binding Domains

2000 ◽  
Vol 2000 (47) ◽  
pp. tw12-tw12
Keyword(s):  
Lipid Binding ◽  
Binding Domains
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