Hearing with the mouthparts: behavioural responses and the structural basis of ultrasound perception in acherontiine hawkmoths

In contrast to previous assumptions, mouthparts form hearing organs not only in choerocampine hawkmoths but also in some distantly related acherontiine hawkmoth species. Four of the six acherontiine species studied revealed responses to ultrasonic sounds when stimulated during tethered flight. The responses included changes in flight speed and non-directional turns. Individuals from two species also responded by emitting sound. The minimum thresholds of the flight pattern changes were approximately 70 dB in all species studied, with species-specific best frequencies between 30 and 70 kHz. Some acherontiine species also move their tongue in a stereotyped way when stimulated acoustically. The activity of the muscles involved in this tongue reflex was characterized in the present study and used in combination with ablation experiments to localize the hearing organ. These experiments revealed auditory functions of the labial palps and the labral pilifers similar to those found in Choerocampina. The palp contributes a 20–25 dB rise in sensitivity, whereas the pilifer appears to contain the sensory organ. Structural differences suggest a convergent evolution of hearing in hawkmoths: in the place of the swollen palps of Choerocampina, acherontiine species capable of hearing possess a scale-plate of the palps that interacts with an articulating pilifer, while this modification is absent in closely related non-hearing species.

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Visualization of Head–Head Interactions in the Inhibited State of Smooth Muscle Myosin

The Journal of Cell Biology ◽

10.1083/jcb.147.7.1385 ◽

1999 ◽

Vol 147 (7) ◽

pp. 1385-1390 ◽

Cited By ~ 84

Author(s):

Thomas Wendt ◽

Dianne Taylor ◽

Terri Messier ◽

Kathleen M. Trybus ◽

Kenneth A. Taylor

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Myosin ◽

Intramolecular Interactions ◽

Actin Binding ◽

Structural Basis ◽

Binding Interface ◽

Structural Differences ◽

Muscle Myosin ◽

Positively Charged ◽

Phosphoryla Tion

The structural basis for the phosphoryla- tion-dependent regulation of smooth muscle myosin ATPase activity was investigated by forming two- dimensional (2-D) crystalline arrays of expressed unphosphorylated and thiophosphorylated smooth muscle heavy meromyosin (HMM) on positively charged lipid monolayers. A comparison of averaged 2-D projections of both forms at 2.3-nm resolution reveals distinct structural differences. In the active, thiophosphorylated form, the two heads of HMM interact intermolecularly with adjacent molecules. In the unphosphorylated or inhibited state, intramolecular interactions position the actin-binding interface of one head onto the converter domain of the second head, thus providing a mechanism whereby the activity of both heads could be inhibited.

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Convergent evolution in Arabidopsis halleri and Arabidopsis arenosa on calamine metalliferous soils

10.1101/459362 ◽

2018 ◽

Cited By ~ 1

Author(s):

Veronica Preite ◽

Christian Sailer ◽

Lara Syllwasschy ◽

Sian Bray ◽

Ute Krämer ◽

...

Keyword(s):

Convergent Evolution ◽

Arabidopsis Halleri ◽

Individual Genome ◽

Genetic Changes ◽

Association Analyses ◽

Systematic Testing ◽

Related Plant ◽

Arabidopsis Arenosa ◽

Species Specific ◽

Degree Of Convergence

AbstractIt is a plausible hypothesis that parallel adaptation events to the same environmental challenge should result in genetic changes of similar or identical effects, depending on the underlying fitness landscapes. However, systematic testing of this is scarce. Here we examine this hypothesis in two closely related plant species, Arabidopsis halleri and Arabidopsis arenosa, which co-occur at two calamine metalliferous sites harbouring toxic levels of the heavy metals zinc and cadmium. We conduct individual genome resequencing alongside soil elemental analysis for 64 plants from 8 populations on metalliferous and non-metalliferous soils, and identify genomic footprints of selection and local adaptation. Selective sweep and environmental association analyses indicate a modest degree of gene as well as functional network convergence, whereby the proximal molecular factors mediating this convergence mostly differ between site pairs and species. Notably, we observe repeated selection on identical SNPs in several A. halleri genes at two independently colonized metalliferous sites. Our data suggest that species-specific metal handling and other biological features could explain a low degree of convergence between species. The parallel establishment of plant populations on calamine metalliferous soils involves convergent evolution, which will likely be more pervasive across sites purposely chosen for maximal similarity in soil composition.

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SARS-CoV-2 RBD in vitro evolution parrots and predicts contagious mutation spread

10.21203/rs.3.rs-183310/v1 ◽

2021 ◽

Author(s):

Gideon Schreiber ◽

Jiri Zahradník ◽

Shir Marciano ◽

Maya Shemesh ◽

Eyal Zoler ◽

...

Keyword(s):

South African ◽

Convergent Evolution ◽

Vaccine Development ◽

Spike Protein ◽

Structural Basis ◽

Receptor Binding Domain ◽

In Vitro Evolution ◽

High Affinity ◽

Future Drug

Abstract SARS-CoV-2 is continually evolving, with more contagious mutations spreading rapidly. Using in vitro evolution to affinity maturate the receptor-binding domain (RBD) of the spike protein towards ACE2 resulted in the more contagious mutations, S477N, E484K, and N501Y, to be among the first selected, explaining the convergent evolution of the “European” (20E-EU1), “British” (501.V1),”South African” (501.V2), and Brazilian variants (501.V3). Plotting the binding affinity to ACE2 of all RBD mutations against their incidence in the population shows a strong correlation between the two. Further in vitro evolution enhancing binding by 600-fold provides guidelines towards potentially new evolving mutations with even higher infectivity. For example, Q498R epistatic to N501Y. Nevertheless, the high-affinity RBD is also an efficient drug, inhibiting SARS-CoV-2 infection. The 2.9Å Cryo-EM structure of the high-affinity complex, including all rapidly spreading mutations, provides a structural basis for future drug and vaccine development and for in silico evaluation of known antibodies.

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Structural basis for divergent and convergent evolution of catalytic machineries in plant aromatic amino acid decarboxylase proteins

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1920097117 ◽

2020 ◽

Vol 117 (20) ◽

pp. 10806-10817 ◽

Cited By ~ 6

Author(s):

Michael P. Torrens-Spence ◽

Ying-Chih Chiang ◽

Tyler Smith ◽

Maria A. Vicent ◽

Yi Wang ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Convergent Evolution ◽

Structural Features ◽

Divergent Evolution ◽

Structural Basis ◽

Acid Decarboxylase ◽

Substrate Selectivity ◽

Amino Acid Decarboxylase ◽

Catalytic Mechanisms

Radiation of the plant pyridoxal 5′-phosphate (PLP)-dependent aromatic l-amino acid decarboxylase (AAAD) family has yielded an array of paralogous enzymes exhibiting divergent substrate preferences and catalytic mechanisms. Plant AAADs catalyze either the decarboxylation or decarboxylation-dependent oxidative deamination of aromatic l-amino acids to produce aromatic monoamines or aromatic acetaldehydes, respectively. These compounds serve as key precursors for the biosynthesis of several important classes of plant natural products, including indole alkaloids, benzylisoquinoline alkaloids, hydroxycinnamic acid amides, phenylacetaldehyde-derived floral volatiles, and tyrosol derivatives. Here, we present the crystal structures of four functionally distinct plant AAAD paralogs. Through structural and functional analyses, we identify variable structural features of the substrate-binding pocket that underlie the divergent evolution of substrate selectivity toward indole, phenyl, or hydroxyphenyl amino acids in plant AAADs. Moreover, we describe two mechanistic classes of independently arising mutations in AAAD paralogs leading to the convergent evolution of the derived aldehyde synthase activity. Applying knowledge learned from this study, we successfully engineered a shortened benzylisoquinoline alkaloid pathway to produce (S)-norcoclaurine in yeast. This work highlights the pliability of the AAAD fold that allows change of substrate selectivity and access to alternative catalytic mechanisms with only a few mutations.

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Preliminary investigations of behavioural and physiological responses to castration in horses

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200011716 ◽

2003 ◽

Vol 2003 ◽

pp. 12-12

Author(s):

R. A. Eager ◽

J. Price ◽

E. Welsh ◽

N. K. Waran

Keyword(s):

Pain Assessment ◽

Physiological Responses ◽

Human Interaction ◽

Physiological Indicators ◽

Behavioural Responses ◽

Welfare Issue ◽

Recent Debate ◽

Equine Welfare ◽

Species Specific ◽

Pain Responses

Behavioural responses to pain are highly species specific and reflect varying strategies for survival. As prey animals, horses may fail to show obvious pain responses, instead masking pain to reduce predation through selection as the weakest of a group (Anil et al., 2002). Price et al. (2002) identified disagreement amongst vets regarding pain assessment and management in horses. This was highlighted by recent debate concerning the existence of post-castration pain and the necessity for analgesia in equines (e.g., Capner 2001; Green 2001). While optimal assessment and management of pain is an important equine welfare issue, the behaviours of horses in response to pain are poorly defined (Raekallio et al. 1997) and the relevance of physiological indicators not confirmed. Palpation or human interaction tests, used in other species (e.g. Holton et al 1998), have yet to be validated in horses. This study aimed to identify and quantify potential behavioural indicators of post-castration pain in horses.

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Active-pocket size differentiating insectile from bacterial chitinolytic β-N-acetyl-D-hexosaminidases

Biochemical Journal ◽

10.1042/bj20110390 ◽

2011 ◽

Vol 438 (3) ◽

pp. 467-474 ◽

Cited By ~ 28

Author(s):

Tian Liu ◽

Haitao Zhang ◽

Fengyi Liu ◽

Lei Chen ◽

Xu Shen ◽

...

Keyword(s):

Active Site ◽

Glycoside Hydrolase Family ◽

Complex Structures ◽

Ostrinia Furnacalis ◽

Wild Type ◽

Structural Differences ◽

Streptomyces Plicatus ◽

Species Specific ◽

Micro Organisms ◽

Hydrolase Family

Chitinolytic β-N-acetyl-D-hexosaminidase is a branch of the GH20 (glycoside hydrolase family 20) β-N-acetyl-D-hexosaminidases that is only distributed in insects and micro-organisms, and is therefore a potential target for the action of insecticides. PUGNAc [O-(2-acetamido-2-deoxy-D-glucopyransylidene)-amino-N-phenylcarbamate] was initially identified as an inhibitor against GH20 β-N-acetyl-D-hexosaminidases. So far no crystal structure of PUGNAc in complex with any GH20 β-N-acetyl-D-hexosaminidase has been reported. We show in the present study that the sensitivities of chitinolytic β-N-acetyl-D-hexosaminidases towards PUGNAc can vary by 100-fold, with the order being OfHex1 (Ostrinia furnacalis β-N-acetyl-D-hexosaminidase)<SmCHB (Serratia marcescens chitobiase)<SpHex (Streptomyces plicatus β-N-acetyl-D-hexosaminidase). To explain this difference, the crystal structures of wild-type OfHex1 as well as mutant OfHex1(V327G) in complex with PUGNAc were determined at 2.0 Å (1 Å=0.1 nm) and 2.3 Å resolutions and aligned with the complex structures of SpHex and SmCHB. The results showed that the sensitivities of these enzymes to PUGNAc were determined by the active pocket size, with OfHex1 having the largest but narrowest entrance, whereas SpHex has the smallest entrance, suitable for holding the inhibitor, and SmCHB has the widest entrance. By widening the size of the active pocket entrance of OfHex1 through replacing the active site Val327 with a glycine residue, the sensitivity of OfHex1 to PUGNAc became similar to that of SmCHB. The structural differences among chitinolytic β-N-acetyl-D-hexosaminidases leading to different sensitivities to PUGNAc may be useful for developing species-specific pesticides and bactericides.

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Structural Basis for a Species-Specific Determinant of an SIV Vif Protein toward Hominid APOBEC3G Antagonism

Cell Host & Microbe ◽

10.1016/j.chom.2019.10.014 ◽

2019 ◽

Vol 26 (6) ◽

pp. 739-747.e4 ◽

Cited By ~ 3

Author(s):

Jennifer M. Binning ◽

Nicholas M. Chesarino ◽

Michael Emerman ◽

John D. Gross

Keyword(s):

Structural Basis ◽

Species Specific ◽

Vif Protein ◽

Specific Determinant

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Understanding the impacts of self-shuffling approach on structure and function of shuffled endoglucanase enzyme via MD simulations

Turkish Journal of Biochemistry ◽

10.1515/tjb-2018-0180 ◽

2020 ◽

Vol 45 (2) ◽

Author(s):

Aslı Yenenler ◽

Umut Gerlevik ◽

Ugur Sezerman

Keyword(s):

Experimental Studies ◽

Salt Bridge ◽

Md Simulations ◽

Structure And Function ◽

Computational Approach ◽

Intramolecular Interactions ◽

Structural Basis ◽

Functional Differences ◽

Structural Differences ◽

And Function

AbstractObjectiveWe identify the impacts of structural differences on functionality of EG3_S2 endoglucanase enzyme with MD studies. The results of previous experimental studies have been explained in details with computational approach. The objective of this study is to explain the functional differences between shuffled enzyme (EG3_S2) and its native counterpart (EG3_nat) from Trichoderma reseei, via Molecular Dynamics approach.Materials and methodsFor this purpose, we performed MD simulations along 30 ns at three different reaction temperatures collected as NpT ensemble, and then monitored the backbone motion, flexibilities of residues, and intramolecular interactions of EG3_S2 and EG3_nat enzymes.ResultsAccording to MD results, we conclude that EG3_S2 and EG3_nat enzymes have unique RMSD patterns, e.g. RMSD pattern of EG3_S2 is more dynamic than that of EG3_nat at all temperatures. In addition to this dynamicity, EG3_S2 establishes more salt bridge interactions than EG3_nat.ConclusionBy taking these results into an account with the preservation of catalytic Glu residues in a proper manner, we explain the structural basis of differences between shuffled and native enzyme via molecular dynamic studies.

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