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Young MW, Flaim ND, Virga JQ, Kantounis SK, Granatosky MC. Mechanical constraints during vertical climbing reveals limited deviation from theoretical minimums. Integr Comp Biol 2024:icae029. [PMID: 38688872 DOI: 10.1093/icb/icae029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024] Open
Abstract
Center of mass (COM) mechanics, often used as an energetic proxy during locomotion, has primarily focused on level movement and hardly explores climbing scenarios. This study examines three-dimensional COM movements across five phylogenetically-distinct species (0.008 kg - 84 kg) to test theoretical expectations of climbing costs, explore how interspecific variation (different limb numbers, adhesion mechanisms, body masses, limb postures) affects COM mechanics, and determine the impact of out-of-plane COM movements on climbing costs. A parallel experiment with rosy-faced lovebirds explores how inclination angle affects COM mechanical energy and how these empirical data align with theoretical expectations. Results indicate that irrespective of anatomical differences, total mechanical costs of climbing are primarily driven by potential energy, outweighing contributions from total kinetic energy. Despite species exhibiting significant out-of-plane kinematics, these movements have minimal impact on overall locomotor costs. Inclination angle changes have minimal effects, as potential energy accumulation dominates quickly as steepness increases, suggesting climbing occurs even on acutely angled substrates from a center of mass perspective. The study challenges prior assumptions about factors influencing climbing costs, such as body mass, speed, or posture, indicating a lack of evident anatomical or behavioral adaptations for climbing efficiency across species. The research sheds light on the universal challenges posed by the mechanical demands of scaling vertical substrates, offering valuable insights for functional morphologists studying climbing behaviors in extant and fossilized species.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
| | - Nicholas D Flaim
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
| | - James Q Virga
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
| | - Stratos K Kantounis
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, 11568, New York
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Young MW, Dickinson E, Gustafson JA, Granatosky MC. Center of mass position does not drive energetic costs during climbing. J Exp Biol 2024; 227:jeb246943. [PMID: 38511508 DOI: 10.1242/jeb.246943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 03/14/2024] [Indexed: 03/22/2024]
Abstract
Climbing animals theoretically should optimize the energetic costs of vertical climbing while also maintaining stability. Many modifications to climbing behaviors have been proposed as methods of satisfying these criteria, focusing on controlling the center of mass (COM) during ascent. However, the link between COM movements and metabolic energy costs has yet to be evaluated empirically. In this study, we manipulated climbing conditions across three experimental setups to elicit changes in COM position, and measured the impact of these changes upon metabolic costs across a sample of 14 humans. Metabolic energy was assessed via open flow respirometry, while COM movements were tracked both automatically and manually. Our findings demonstrate that, despite inducing variation in COM position, the energetic costs of climbing remained consistent across all three setups. Differences in energetic costs were similarly not affected by body mass; however, velocity had a significant impact upon both cost of transport and cost of locomotion, but such a relationship disappeared when accounting for metabolic costs per stride. These findings suggest that climbing has inescapable metabolic demands driven by gaining height, and that attempts to mitigate such a cost, with perhaps the exception of increasing speed, have only minimal impacts. We also demonstrate that metabolic and mechanical energy costs are largely uncorrelated. Collectively, we argue that these data refute the idea that efficient locomotion is the primary aim during climbing. Instead, adaptations towards effective climbing should focus on stability and reducing the risk of falling, as opposed to enhancing the metabolic efficiency of locomotion.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Jon A Gustafson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
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Young MW, English HM, Dickinson E, Kantounis SJ, Chernik ND, Cannata MJ, Lynch SK, Jacobson RN, Virga JQ, Lopez A, Granatosky MC. Comparative kinetics of humans and non-human primates during vertical climbing. J Exp Biol 2024; 227:jeb247012. [PMID: 38426398 DOI: 10.1242/jeb.247012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 02/19/2024] [Indexed: 03/02/2024]
Abstract
Climbing represents a critical behavior in the context of primate evolution. However, anatomically modern human populations are considered ill-suited for climbing. This adaptation can be attributed to the evolution of striding bipedalism, redirecting anatomical traits away from efficient climbing. Although prior studies have speculated on the kinetic consequences of this anatomical reorganization, there is a lack of data on the force profiles of human climbers. This study utilized high-speed videography and force plate analysis to assess single limb forces during climbing from 44 human participants of varying climbing experience and compared these data with climbing data from eight species of non-human primates (anthropoids and strepsirrhines). Contrary to expectations, experience level had no significant effect on the magnitude of single limb forces in humans. Experienced climbers did, however, demonstrate a predictable relationship between center of mass position and peak normal forces, suggesting a better ability to modulate forces during climbing. Humans exhibited significantly higher peak propulsive forces in the hindlimb compared with the forelimb and greater hindlimb dominance overall compared with non-human primates. All species sampled demonstrated exclusively tensile forelimbs and predominantly compressive hindlimbs. Strepsirrhines exhibited a pull-push transition in normal forces, while anthropoid primates, including humans, did not. Climbing force profiles are remarkably stereotyped across humans, reflecting the universal mechanical demands of this form of locomotion. Extreme functional differentiation between forelimbs and hindlimbs in humans may help to explain the evolution of bipedalism in ancestrally climbing hominoids.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Hannah M English
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Stratos J Kantounis
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Noah D Chernik
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Matthew J Cannata
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Samantha K Lynch
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Reuben N Jacobson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - James Q Virga
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Alexander Lopez
- School of Health Professions, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Inclusive Sports and Fitness, Holbrook, NY 11741, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
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Young MW, Webster C, Tanis D, Schurr AF, Hanna CS, Lynch SK, Ratkiewicz AS, Dickinson E, Kong FH, Granatosky MC. What does climbing mean exactly? Assessing spatiotemporal gait characteristics of inclined locomotion in parrots. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:19-33. [PMID: 37140643 DOI: 10.1007/s00359-023-01630-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 03/20/2023] [Accepted: 04/03/2023] [Indexed: 05/05/2023]
Abstract
At what inclination does climbing begin? In this paper, we investigate the transition from walking to climbing in two species of parrot (Agapornis roseicollis and Nymphicus hollandicus) that are known to incorporate both their tail and their craniocervical system into the gait cycle during vertical climbing. Locomotor behaviors ranging in inclination were observed at angles between 0° and 90° for A. roseicollis, and 45°-85° degrees for N. hollandicus. Use of the tail in both species was observed at 45° inclination, and was joined at higher inclinations (> 65°) by use of the craniocervical system. Additionally, as inclination approached (but remained below) 90°, locomotor speeds were reduced while gaits were characterized by higher duty factors and lower stride frequency. These gait changes are consistent with those thought to increase stability. At 90°, A. roseicollis significantly increased its stride length, resulting in higher overall locomotor speed. Collectively these data demonstrate that the transition between horizontal walking and vertical climbing is gradual, incrementally altering several components of gait as inclinations increase. Such data underscore the need for further investigation into how exactly "climbing" is defined and the specific locomotor characteristics that differentiate this behavior from level walking.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Clyde Webster
- School of Mechanical and Mechatronic Engineering, The University of Technology Sydney (UTS), Sydney, Australia
| | - Daniel Tanis
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Alissa F Schurr
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Christopher S Hanna
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Samantha K Lynch
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Aleksandra S Ratkiewicz
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Felix H Kong
- School of Mechanical and Mechatronic Engineering, The University of Technology Sydney (UTS), Sydney, Australia
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA.
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA.
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Dickinson E, Young MW, Granatosky MC. Beakiation: how a novel parrot gait expands the locomotor repertoire of living birds. R Soc Open Sci 2024; 11:231397. [PMID: 38298389 PMCID: PMC10827422 DOI: 10.1098/rsos.231397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/02/2024] [Indexed: 02/02/2024]
Abstract
Occupation of arboreal habitats poses myriad locomotor challenges, driving both anatomical and behavioural innovations across various tetrapod lineages. Here, we report and biomechanically assess a novel, beak-driven locomotor mode-'beakiation'-by which parrots advance along the underside of narrow arboreal substrates. Using high-speed videography and kinetic analyses, we describe the limb loading patterns and pendular mechanics of beakiation, and compare the biomechanical characteristics of this gait with other suspensory behaviours (namely, forelimb-driven brachiation and inverted quadrupedal walking). We report that the parrot beak experiences comparable force magnitudes (approx. 150% body weight in the normal plane; approx. 50% body weight in the fore-aft plane) to the forelimbs of brachiating primates. Parrot beakiation is also characterized by longer-than-expected pendular periods, similar to observations of gibbon brachiation. However, in terms of mechanical energy recovery, beakiation is typified by lower levels of energetic recovery than brachiating specialists: a product of its slower, more careful nature. The observation of this novel behaviour-which adds to a growing base of literature regarding beak-assisted locomotor strategies in birds-highlights the extraordinary behavioural plasticity of birds, the functional versatility of the avian beak, and the difficulties in reconstructing an animal's locomotor repertoire from morphological characteristics alone.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY, USA
| | - Melody W. Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY, USA
| | - Michael C. Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY, USA
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Dickinson E, Young MW, Kim CJ, Hadjiargyrou M, Granatosky MC. Correction: The influence of substrate size upon pulling and gripping forces in parrots (Psittaciformes: Agapornis roseicollis). J Exp Biol 2024; 227:jeb246958. [PMID: 38165209 DOI: 10.1242/jeb.246958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
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Young MW, Wilken AT, Manafzadeh AR, Schurr AF, Bastian A, Dickinson E, Granatosky MC. The dual function of prokinesis in the feeding and locomotor systems of parrots. J Exp Biol 2023; 226:jeb246659. [PMID: 37942661 PMCID: PMC10730085 DOI: 10.1242/jeb.246659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 10/27/2023] [Indexed: 11/10/2023]
Abstract
Prokinesis, a mode of avian cranial kinesis involving motion between the neurocranium and upper beak, has long been investigated in biomechanical analyses of avian feeding and drinking. However, the modern avian beak is also used for non-feeding functions. Here, we investigate the dual function of prokinesis in the feeding and locomotor systems of the rosy-faced lovebird (Agapornis roseicollis). Lovebirds and other parrots utilize their beak both during feeding and as a third limb during vertical climbing. Thus, we experimentally measured both force-generating potential and movement of the rosy-faced lovebird mandible and maxilla (via prokinetic flexion of the craniofacial hinge) during tripedal climbing and mandibular/maxillary adduction. We found that whereas the maxilla is primarily responsible for generating force during locomotion, the mandible is primarily responsible for generating force during forceful jaw adduction, hinting at a remarkable capacity to alter prokinetic function with differing neuromuscular control. The ability of the prokinetic apparatus to perform functions with competing optimality criteria via modulation of motor control illustrates the functional plasticity of the avian cranial kinesis and sheds new light on the adaptive significance of cranial mobility.
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Affiliation(s)
- Melody W. Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Alec T. Wilken
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
| | - Armita R. Manafzadeh
- Yale Institute for Biospheric Studies, Yale University, New Haven, CT 06520, USA
- Department of Earth & Planetary Sciences, Yale University, New Haven, CT 06520, USA
- Yale Peabody Museum of Natural History, New Haven, CT 06520, USA
- Department of Mechanical Engineering & Materials Science, Yale University, New Haven, CT 06520, USA
| | - Alissa F. Schurr
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Aaron Bastian
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Michael C. Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
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Kim CJ, Singh C, Kaczmarek M, O'Donnell M, Lee C, DiMagno K, Young MW, Letsou W, Ramos RL, Granatosky MC, Hadjiargyrou M. Mustn1 ablation in skeletal muscle results in functional alterations. FASEB Bioadv 2023; 5:541-557. [PMID: 38094159 PMCID: PMC10714068 DOI: 10.1096/fba.2023-00082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 02/01/2024] Open
Abstract
Mustn1, a gene expressed exclusively in the musculoskeletal system, was shown in previous in vitro studies to be a key regulator of myogenic differentiation and myofusion. Other studies also showed Mustn1 expression associated with skeletal muscle development and hypertrophy. However, its specific role in skeletal muscle function remains unclear. This study sought to investigate the effects of Mustn1 in a conditional knockout (KO) mouse model in Pax7 positive skeletal muscle satellite cells. Specifically, we investigated the potential effects of Mustn1 on myogenic gene expression, grip strength, alterations in gait, ex vivo investigations of isolated skeletal muscle isometric contractions, and potential changes in the composition of muscle fiber types. Results indicate that Mustn1 KO mice did not present any substantial phenotypic changes or significant variations in genes related to myogenic differentiation and fusion. However, an approximately 10% decrease in overall grip strength was observed in the 2-month-old KO mice in comparison to the control wild type (WT), but this decrease was not significant when normalized by weight. KO mice also generated approximately 8% higher vertical force than WT at 4 months in the hindlimb. Ex vivo experiments revealed decreases in about 20 to 50% in skeletal muscle contractions and about 10%-20% fatigue in soleus of both 2- and 4-month-old KO mice, respectively. Lastly, immunofluorescent analyses showed a persistent increase of Type IIb fibers up to 15-fold in the KO mice while Type I fibers decreased about 20% and 30% at both 2 and 4 months, respectively. These findings suggest a potential adaptive or compensatory mechanism following Mustn1 loss, as well as hinting at an association between Mustn1 and muscle fiber typing. Collectively, Mustn1's complex roles in skeletal muscle physiology requires further research, particularly in terms of understanding the potential role of Mustn1 in muscle repair and regeneration, as well as with influence of exercise. Collectively, these will offer valuable insights into Mustn1's key biological functions and regulatory pathways.
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Affiliation(s)
- Charles J. Kim
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
- Department of Biological and Chemical SciencesNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Chanpreet Singh
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Marina Kaczmarek
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Madison O'Donnell
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Christine Lee
- Department of Biological and Chemical SciencesNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Kevin DiMagno
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Melody W. Young
- Department of Anatomy, College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - William Letsou
- Department of Biological and Chemical SciencesNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Raddy L. Ramos
- Department of Biomedical Sciences, College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Michael C. Granatosky
- Department of Anatomy, College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
- Center for Biomedical InnovationNew York Institute of TechnologyOld WestburyNew YorkUSA
| | - Michael Hadjiargyrou
- College of Osteopathic MedicineNew York Institute of TechnologyOld WestburyNew YorkUSA
- Department of Biological and Chemical SciencesNew York Institute of TechnologyOld WestburyNew YorkUSA
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Dickinson E, Young MW, Flaim ND, Sawiec A, Granatosky MC. A functional framework for interpreting phalangeal form. J R Soc Interface 2023; 20:20230251. [PMID: 37582408 PMCID: PMC10427194 DOI: 10.1098/rsif.2023.0251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
Across tetrapods, the proportional lengths of the manual and pedal phalanges are highly constrained, following a generalized blueprint of shortening in a proximodistal gradient. Despite this, several lineages of both mammals (e.g. sloths, bats and colugos) and birds (e.g. raptors, parrots and woodpeckers) have broken this pattern, shortening the proximal phalanx while elongating more distal elements. As yet, no unifying explanation for this convergence has been empirically evaluated. This study combines a comparative phylogenetic assessment of phalangeal morphology across mammals and birds with a novel bioinspired robotics approach to explicitly test functional hypotheses relating to these morphotypes. We demonstrate that shortening the proximal phalanx allows taxa to maximize forces produced at the proximal interphalangeal joint, while elongation of subsequent elements maintains total ray length-ensuring arboreal species can still enclose large-diameter supports. Within suspensory and vertically clinging mammals, we additionally observe a secondary adaptation towards maximizing grip strength: namely increasing the height of the trochleae to increase the moment arm of digital flexor muscles that cross the joint. Together, our analyses highlight that numerous tetrapod lineages independently converged upon this morphotype to maximize proximal gripping strength, an adaptation to support specialized hunting and locomotor behaviours.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Melody W. Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Nicholas D. Flaim
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Aleksander Sawiec
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Michael C. Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
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Ekhator C, Varshney A, Young MW, Tanis D, Granatosky MC, Diaz RE, Molnar JL. Locomotor characteristics of the ground-walking chameleon Brookesia superciliaris. J Exp Zool A Ecol Integr Physiol 2023; 339:602-614. [PMID: 37260090 DOI: 10.1002/jez.2703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 06/02/2023]
Abstract
Understanding the locomotor characteristics of early diverging ground-walking chameleons (members of the genera Brookesia, Rhampholeon, Palleon, and Rieppeleon) can help to explain how their unique morphology is adapted to fit their environment and mode of life. However, nearly all quantitative studies of chameleon locomotion thus far have focused on the larger "true arboreal" chameleons. We investigated kinematics and spatiotemporal gait characteristics of the Brown Leaf Chameleon (Brookesia superciliaris) on different substrates and compared them with true arboreal chameleons, nonchameleon lizards, and other small arboreal animals. Brookesia exhibits a combination of locomotor traits, some of which are traditionally arboreal, others more terrestrial, and a few that are very unusual. Like other chameleons, Brookesia moved more slowly on narrow dowels than on broad planks (simulating arboreal and terrestrial substrates, respectively), and its speed was primarily regulated by stride frequency rather than stride length. While Brookesia exhibits the traditionally arboreal trait of a high degree of humeral protraction at the beginning of stance, unlike most arboreal tetrapods, it uses smaller shoulder and hip excursions on narrower substrates, possibly reflecting its more terrestrial habits. When moving at very slow speeds, Brookesia often adopts an unusual footfall pattern, lateral-sequence lateral-couplets. Because Brookesia is a member of one of the earliest-diverging groups of chameleons, its locomotion may provide a good model for an intermediate stage in the evolution of arboreal chameleons. Thus, the transition to a fully arboreal way of life in "true arboreal" chameleons may have involved changes in spatiotemporal and kinematic characteristics as well as morphology.
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Affiliation(s)
- Chukwuyem Ekhator
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | | | - Melody W Young
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Daniel Tanis
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Michael C Granatosky
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
- Center for Biomedical Innovation College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Raul E Diaz
- Department of Biological Sciences, California State University, Los Angeles, California, USA
| | - Julia L Molnar
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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Dickinson E, Young MW, Tanis D, Granatosky MC. Patterns and Factors Influencing Parrot (Order: Psittaciformes) Success in Establishing Thriving Naturalized Populations within the Contiguous United States. Animals (Basel) 2023; 13:2101. [PMID: 37443899 DOI: 10.3390/ani13132101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/20/2023] [Accepted: 06/21/2023] [Indexed: 07/15/2023] Open
Abstract
Parrots (Order: Psittaciformes) represent one of the most striking and ecomorphologically diverse avian clades, spanning more than two orders of magnitude in body size with populations occupying six continents. The worldwide diaspora of parrots is largely due to the pet trade, driven by human desire for bright, colorful, and intelligent animals as companions. Some introduced species have aptly inserted themselves into the local ecosystem and established successful breeding colonies all around the globe. Notably, the United States is home to several thriving populations of introduced species including red-masked parakeets (Psittacara erythrogenys), monk parakeets (Myiopsitta monachus), nanday conures (Aratinga nenday), and red-crowned amazons (Amazona viridigenalis). Their incredible success globally begs the question as to how these birds adapt so readily to novel environments. In this commentary, we trace parrots through evolutionary history, contextualize existent naturalized parrot populations within the contiguous United States, and provide a phylogenetic regression analysis of body mass and brain size based on success in establishing breeding populations. The propensity for a parrot species to become established appears to be phylogenetically driven. Notably, parrots in the family Cacatuidae and Neotropical Pyrrhua appear to be poor at establishing themselves in the United States once released. Although brain size among Psittaciformes did not show a significant impact on successful breeding in the continental United States, we propose that the success of parrots can be attributed to their charismatic nature, significant intelligence relative to other avian lineages, and behavioral flexibility.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - Melody W Young
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - Daniel Tanis
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - Michael C Granatosky
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
- Center for Biomedical Innovation, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
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12
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Dickinson E, Young MW, DeLeon D, Bas B, Zou B, Ratkiewicz A, Beatty BL, Granatosky MC. Tail feather strength in tail-assisted climbing birds is achieved through geometric, not material change. Proc Biol Sci 2023; 290:20222325. [PMID: 37161328 PMCID: PMC10170200 DOI: 10.1098/rspb.2022.2325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 04/18/2023] [Indexed: 05/11/2023] Open
Abstract
Birds encompass vast ecomorphological diversity and practise numerous distinct locomotor modes. One oft-cited feature seen in climbing birds is an increase in tail 'stiffness', yet it remains unclear to what extent these feathers are altered, and the specific mechanism by which differences in functional performance are attained. We collected a broad taxonomic sample of tail feathers (6525 total, from 774 species representing 21 avian orders and ranging in size from approximately 3 g to greater than 11 kg) and present data on their material properties, cross-sectional geometry and morphometrics. Ordinary and phylogenetic least-squares regressions of each variable versus body mass were conducted to assess scaling relationships and demonstrate that tail-supported climbers exhibit longer tail feathers with a wider rachis base and tip, and a greater second moment of area and maximum bending moment. However, no differences were observed in the material properties of the keratin itself. This suggests that tail-supported arboreal climbing birds of multiple orders have independently adopted similar morphologies. Moreover, these geometric relationships follow the same allometric scaling relationships as seen in the long bones of mammalian limbs, suggesting that the morphology of these developmentally and evolutionarily distinct structures are governed by similar functional constraints of weight support.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Melody W. Young
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - David DeLeon
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Burcak Bas
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Bettina Zou
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Aleksandra Ratkiewicz
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
| | - Brian L. Beatty
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Department of Paleobiology, National Museum of Natural History, Washington, DC 20560, USA
| | - Michael C. Granatosky
- Department of Anatomy New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568, USA
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13
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Young MW, Virga JQ, Kantounis SJ, Lynch SK, Chernik ND, Gustafson JA, Cannata MJ, Flaim ND, Granatosky MC. How Pendular Is Human Brachiation? When Form Does Not Follow Function. Animals (Basel) 2023; 13:ani13091438. [PMID: 37174475 PMCID: PMC10177241 DOI: 10.3390/ani13091438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/07/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023] Open
Abstract
Brachiation is a form of suspensory locomotion observed only in Primates. The non-human hominoids (e.g., gibbons, orangutans, chimpanzees, and gorillas) are considered specialized brachiators, yet peculiar among the living apes are anatomically modern humans (Homo sapiens), who have forgone this locomotor mode in favor of bipedal striding. Humans can, however, brachiate and seem to have retained the locomotor capabilities of their arboreal ancestors. However, the mechanics of human brachiation have not been quantified. In this study, we evaluate how closely human brachiation conforms to the expectations of simple pendular motion using triaxial accelerometry and high-speed videography. These data are compared to specialized brachiating non-human primates. We found that humans have lower energy recovery than siamangs (Symphalangus syndactylus) during brachiation and have shorter observed pendular periods than expected compared to other primates. We demonstrate that relatively long forelimb length and high grip forces, a proxy for global forelimb force-generating potential, act as the main driving factors to reduce energetic costs through effective pendular recovery. These data are the first to assess the strategies humans adopt to perform a behavior they are not anatomically specialized to execute and places them within a comparative framework amongst other brachiating primates. We show that although humans demonstrate behavioral flexibility during brachiation (e.g., differing mediolateral and vertical center of mass positional movement patterns), anatomical features are the primary driver of variation in brachiation performance.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - James Q Virga
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Stratos J Kantounis
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Samantha K Lynch
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Noah D Chernik
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Jon A Gustafson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Matthew J Cannata
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Nicholas D Flaim
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, NY 11568, USA
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14
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McKamy AJ, Young MW, Mossor A, Young JW, Avey-Arroyo JA, Granatosky MC, Butcher MT. Pump the brakes! The hindlimbs of three-toed sloths decelerate and support suspensory locomotion (Bradypus variegatus, Xenarthra). J Exp Biol 2023; 226:297281. [PMID: 36942880 DOI: 10.1242/jeb.245622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/06/2023] [Indexed: 03/23/2023]
Abstract
Modern tree sloths are one of few mammalian taxa for which quadrupedal suspension is obligatory. Sloth limb musculature is specialized for slow velocity, large force contractions that stabilize their body below branches and conserves energy during locomotion. However, it is unknown if two and three-toed sloths converge in their use of limb biomechanics and whether these patterns are comparable to how primates perform arboreal suspensory locomotion. This study addresses this need by collecting limb loading data in three-toed sloths (Bradypus variegatus; N=5) during suspensory walking. Sloths performed locomotor trials at their preferred speed on an instrumented beam apparatus with a force platform as the central supporting segment. Peak forces and impulses of the forelimb and hindlimb were recorded and analyzed in three dimensions. The hindlimbs of B. variegatus apply large braking forces greater in magnitude than peak forces generated by the forelimbs in propulsion, a pattern consistent with that observed in two-toed sloths. However, B. variegatus exhibits hindlimb-biased bodyweight support in vertical peak forces and impulse, with appreciable laterally-directed forces in each limb pair, both of which vary from limb loading distributions in two-toed sloths. Moreover, bodyweight distribution between limb pairs is opposite to that employed by primates during quadrupedal suspension. Thus, there appear to be multiple strategies for achieving suspensory locomotion in arboreal mammals. These differences may be attributable to anatomical variation or phylogenetic position, but as of yet an explanation remains unknown. Future EMG analyses are expected to provide insight into how specific hindlimb muscle groups contribute to braking forces and stabilizing the center of mass of sloths during suspension.
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Affiliation(s)
- Andrew J McKamy
- Department of Chemical and Biological Sciences, Youngstown State University, Youngstown OH, USA
| | - Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, NY, USA
| | - Angela Mossor
- School of Biomedical Sciences, Kent State University, Kent OH, USA
| | - Jesse Wyatt Young
- School of Biomedical Sciences, Kent State University, Kent OH, USA
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown OH, USA
| | - Judy A Avey-Arroyo
- The Sloth Sanctuary of Costa Rica, Penshurst, Limon, Costa Rica, USA
- The Dallas World Aquarium, Dallas, TX, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, NY, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, NY, USA
| | - Michael T Butcher
- Department of Chemical and Biological Sciences, Youngstown State University, Youngstown OH, USA
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15
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Young MW, Flaim ND, Yarbro J, Ragupathi A, Guru N, Dickinson E, Granatosky MC. Dynamics of horizontal walking and vertical climbing in the Australian green tree frog (Ranoidea caerulea). J Exp Biol 2023; 226:306242. [PMID: 36866683 DOI: 10.1242/jeb.244833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 02/24/2023] [Indexed: 03/04/2023]
Abstract
Despite the high mechanical demands associated with climbing, the ability to ascend vertically has evolved independently in most major animal lineages. However, little is known about the kinetics, mechanical energy profiles, or spatiotemporal gait characteristics of this locomotor mode. In this study, we explore the dynamics of horizontal locomotion and vertical climbing on both flat substrates and narrow poles in five Australian green tree frogs (Ranoidea caerulea). Vertical climbing is associated with slow, deliberate movements (i.e., reduced speed and stride frequency and increased duty factors) and propulsive fore-aft impulses in both the forelimb and hindlimb. By comparison, horizontal walking was characterize by a braking forelimb and a propulsive hindlimb. In the normal plane, tree frogs mirrored other taxa in exhibiting a net pulling forelimb and a net pushing hindlimb. In terms of mechanical energy, tree frogs matched theoretical predictions of climbing dynamics (i.e., the total mechanical energetic cost of vertical climbing was predominantly driven by potential energy, with negligible kinetic contributions). Utilizing power as a means for estimating efficiency, we also demonstrate that Australian green tree frogs show total mechanical power costs only slightly above the minimum mechanical power necessary to climb, highlighting their highly effective locomotor mechanics. This study provides new data on climbing dynamics in a slow-moving arboreal tetrapod and raises new testable hypotheses about how natural selection can act upon a locomotor behavior that is notably constrained by external physical forces.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Nicholas D Flaim
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Johnathan Yarbro
- New York Institute of Technology College of Osteopathic Medicine, Jonesboro, Arkansas, USA
| | - Ashwin Ragupathi
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Navjot Guru
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA.,Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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16
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Young MW, McKamy AJ, Dickinson E, Yarbro J, Ragupathi A, Guru N, Avey-Arroyo JA, Butcher MT, Granatosky MC. Three toes and three modes: Dynamics of terrestrial, suspensory, and vertical locomotion in brown-throated three-toed sloths (Bradypodidae, Xenarthra). J Exp Zool A Ecol Integr Physiol 2023; 339:383-397. [PMID: 36747379 DOI: 10.1002/jez.2684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 02/08/2023]
Abstract
Living sloths exhibit numerous anatomical specializations towards inverted quadrupedalism, however, previous studies have noted a more varied locomotor repertoire than previously anticipated. In this study, we present spatiotemporal gait characteristics and triaxial kinetic data from the brown-throated three-toed sloth (Bradypus variegatus) across three locomotor modes: terrestrial quadrupedal "crawling", suspensory walking, and vertical climbing. Compared to quadrupedal crawling and suspensory walking, B. variegatus adopted longer contact times and stride durations, larger duty factors, and greater speed during vertical climbing. Net fore-aft impulses were significantly greater during vertical climbing in both limb pairs than in quadrupedal crawling and suspensory walking. Functionally, during quadrupedal crawling and vertical climbing, both limb pairs served propulsive roles, while differentiation between a propulsive forelimb and braking hindlimb was observed during suspension. Net tangential forces differentiated vertical climbing kinetics from the other modes of locomotion, with the introduction of bidirectional pulling and pushing forces in the forelimb and hindlimb, respectively. The net mediolateral impulses were similar in vertical climbing and quadrupedal crawling as both limb pairs directed forces in one direction, whereas during suspensory walking, the laterally dominant forelimb was opposed by the medially dominant hindlimb. In total, this study provides novel data on the diverse locomotor dynamics in a slow-moving arboreal tetrapod and posits new testable hypotheses about the neuroplasticity and ease of transitioning between locomotor behaviors. The strikingly similar kinetic profiles of quadrupedal crawling and suspensory walking compared to vertical climbing suggest shared neuromuscular and mechanical demands between these mirrored locomotor modes.
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Affiliation(s)
- Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Andrew J McKamy
- Department of Biological Sciences, Youngstown State University, Youngstown, Ohio, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Johnathan Yarbro
- New York Institute of Technology College of Osteopathic Medicine, Jonesboro, Arkansas, USA
| | - Ashwin Ragupathi
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Navjot Guru
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | | | - Michael T Butcher
- Department of Biological Sciences, Youngstown State University, Youngstown, Ohio, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA.,Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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17
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Dickinson E, Young MW, Kim CJ, Hadjiargyrou M, Granatosky MC. The influence of substrate size upon pulling and gripping forces in parrots (Psittaciformes: Agapornis roseicollis). J Exp Biol 2022; 225:jeb244818. [PMID: 36106504 DOI: 10.1242/jeb.244818] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/29/2022] [Indexed: 01/03/2024]
Abstract
The ability to securely grasp substrates of variable diameter is critical to arboreal animals. Arboreal specialists have emerged across several vertebrate lineages - including mammals, lizards and amphibians - and several attempts have been made to quantify their grasping performance, by measuring either gripping (i.e. forces generated about an object or substrate enclosed within the digits) or pulling (i.e. the ability to resist being removed from a substrate) forces. In this study, we present data on both pulling and gripping performance across a range of substrate diameters (0.5-17.5 mm) within a model parrot species (Agapornis roseicollis). Parrots represent an ancient arboreal lineage, allowing us to compare their abilities with those of arboreal specialists within other tetrapod groups. Data were collected using 3D-printed perches of variable diameter, and forces were registered using either an AMTI low-load force plate (grip force) or a Harvard Apparatus portable strength tester (pull force). Gripping forces peaked at a 5 mm diameter perch, while pulling forces were greatest at a 2.5 mm diameter. All forces strongly diminished above 10 mm size, suggesting grip force is optimized when utilizing small perches, a finding which corresponds to observational studies of preferential perching habits among free-ranging parrots. Relative grasping performance (adjusted for body size) in parrots is roughly equivalent to that of other arboreal specialists from other tetrapod lineages, but low when compared with that of raptorial birds that utilize their feet during aerial prey capture. Further taxonomic sampling is encouraged to contextualize how grasping performance varies in an adaptive evolutionary context.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
| | - Melody W Young
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
- College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
| | - Charles J Kim
- College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
| | - Michael Hadjiargyrou
- Department of Biological and Chemical Sciences, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
| | - Michael C Granatosky
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568-8000, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY 11568-8000, USA
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18
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Faltings L, Young MW, Ross CF, Granatosky MC. Got rhythm? Rhythmicity differences reflect different optimality criteria in feeding and locomotor systems. Evolution 2022; 76:2181-2190. [PMID: 35862552 DOI: 10.1111/evo.14569] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/19/2022] [Accepted: 05/24/2022] [Indexed: 01/22/2023]
Abstract
Evolutionary analyses of joint kinematics and muscle mechanics suggest that, during cyclic behaviors, tetrapod feeding systems are optimized for precise application of forces over small displacements during chewing, whereas locomotor systems are more optimized for large and rapid joint excursions during walking and running. If this hypothesis is correct, then it stands to reason that other biomechanical variables in the feeding and locomotor systems should also reflect these divergent functions. We compared rhythmicity of cyclic jaw and limb movements in feeding and locomotor systems in 261 tetrapod species in a phylogenetic context. Accounting for potential confounding variables, our analyses reveal higher rhythmicity of cyclic movements of the limbs than of the jaw. Higher rhythmicity in the locomotor system corroborates a hypothesis of stronger optimization for energetic efficiency: deviation from the limbs' natural frequency results in greater variability of center of mass movements and limb inertial changes, and therefore more work by limb muscles. Relatively lower rhythmicity in the feeding system may be a consequence of the necessity to prevent tooth breakage and wear, the greater complexity of coordination with tongue movements, and/or a greater emphasis on energy storage in elastic elements rather than the kinetics of limb movement.
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Affiliation(s)
- Lukas Faltings
- College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, 11568, USA
| | - Melody W Young
- College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, 11568, USA
- Department of Anatomy, Center for Biomedical Innovation, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, 11568, USA
| | - Callum F Ross
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois, 60637, USA
| | - Michael C Granatosky
- College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, 11568, USA
- Department of Anatomy, Center for Biomedical Innovation, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York, 11568, USA
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19
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Dickinson E, Young MW, Granatosky MC. Testing mechanisms for weight support distribution during inverted quadrupedalism in primates. J Exp Zool A Ecol Integr Physiol 2022; 337:699-708. [PMID: 35567440 DOI: 10.1002/jez.2605] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/13/2022] [Accepted: 04/27/2022] [Indexed: 06/15/2023]
Abstract
A key characteristic of primate above-branch arboreal locomotion is hindlimb-biased weight support, subverting the typical mammalian condition in which the majority of the body weight is supported by the forelimb. This shift is thought to reflect an adaptation toward the arboreal niches exploited by early primates. However, above-branch quadrupedalism represents only one locomotor mode employed by primates in arboreal contexts. Inverted quadrupedal gaits, in which primates are suspended beneath branches by their hands and feet, have been documented in more than 50 primate taxa. This gait is characterized by a return to forelimb-biased weight distributions and a transition from peak vertical forces being greatest in the hindlimb to being greatest in the forelimb, which may occur to protect the hindlimb from high magnitudes of tensile loading when inverted. In this study, we compare kinetic and kinematic data during upright and inverted quadrupedalism in Lemur catta, Varecia variegata, Cebus capucinus, and Saimiri sciureus. These data are referenced against a classical inverted quadrupedal model: the two-toed sloth (Choloepus didactylus). Our findings show that inverted quadrupedalism in primates is differentiated from above-branch quadrupedalism by increases in forelimb weight support, forelimb contact times, and both forelimb and hindlimb joint excursions. Previously postulated biomechanical models outlining mechanisms relating to the control of weight support during upright walking do not translate well to inverted quadrupedal walking. We suggest that inverted primates may simply be adopting basal neuromuscular gait characteristics and applying them facultatively to this infrequent locomotor behavior.
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Affiliation(s)
- Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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20
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Young MW, Lynch SK, Dickinson E, Currier AA, Davoli EC, Hanna CS, Fischer HM, DiUbaldi GA, Granatosky MC. Patterns of single limb forces during terrestrial and arboreal locomotion in rosy-faced lovebirds (Psittaciformes: Agapornis roseicollis). J Exp Biol 2022; 225:276123. [PMID: 35822351 DOI: 10.1242/jeb.244571] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 06/29/2022] [Indexed: 11/20/2022]
Abstract
The biomechanical demands of arboreal locomotion are generally thought to necessitate specialized kinetic and kinematic gait characteristics. While such data has been widely collected across arboreal quadrupeds, no study has yet explored how arboreal substrates influence the locomotor behavior of birds. Parrots - an ancient arboreal lineage that exhibit numerous anatomical specializations towards life in the trees - represent an ideal model group within which to examine this relationship. Here, we quantify limb loading patterns within the rosy-faced lovebird (Agapornis roseicollis) across a range of experimental conditions to define under which circumstances arboreal gaits are triggered, and how, during arboreal walking, gait patterns change across substrates of varying diameter. In so doing, we address longstanding questions as to how the challenges associated with arboreality affect gait parameters. Arboreal locomotion was associated with the adoption of a sidling gait, which was employed exclusively on the small- and medium-poles but not terrestrially. When sidling, the hindlimbs are decoupled into a distinct leading limb (which imparts exclusively braking forces) and trailing limb (which generates only propulsive forces). Sidling was also associated with relatively low pitching forces, even on the smallest substrate. Indeed, these forces were significantly lower than mediolateral forces experienced during striding on terrestrial and large-diameter substrates. We propose that the adoption of sidling gaits is a consequence of avian foot morphology and represents a novel form of arboreal locomotion where inversion/eversion is impossible. Such movement mechanics is likely widespread among avian taxa and may also typify patterns of arboreal locomotion in humans.
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Affiliation(s)
- Melody W Young
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Samantha K Lynch
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Edwin Dickinson
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA.,Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Allen A Currier
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Elizabeth C Davoli
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Christopher S Hanna
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Hannah M Fischer
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Gianluca A DiUbaldi
- New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA.,Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
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21
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Granatosky MC, Toussaint SLD, Young MW, Panyutina A, Youlatos D. The northern treeshrew (Scandentia: Tupaiidae: Tupaia belangeri) in the context of primate locomotor evolution: A comprehensive analysis of gait, positional, and grasping behavior. J Exp Zool A Ecol Integr Physiol 2022; 337:645-665. [PMID: 35451573 DOI: 10.1002/jez.2597] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/25/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
The locomotor behaviors of treeshrews are often reported as scurrying "squirrel-like" movements. As such, treeshrews have received little attention beyond passing remarks in regard to primate locomotor evolution. However, scandentians vary considerably in habitat and substrate use, thus categorizing all treeshrew locomotion based on data collected from a single species is inappropriate. This study presents data on gait characteristics, positional, and grasping behavior of the northern treeshrew (Tupaia belangeri) and compares these findings to the fat-tailed dwarf lemur (Cheirogaleus medius) to assess the role of treeshrews as a model for understanding the origins of primate locomotor and grasping evolution. We found that northern treeshrews were primarily arboreal and shared their activities between quadrupedalism, climbing and leaping in rates similar to fat-tailed dwarf lemurs. During quadrupedal locomotion, they exhibited a mixture of gait characteristics consistent with primates and other small-bodied non-primate mammals and demonstrated a hallucal grasping mode consistent with primates. These data reveal that northern treeshrews show a mosaic of primitive mammalian locomotor characteristics paired with derived primate features. Further, this study raises the possibility that many of the locomotor and grasping characteristics considered to be "uniquely" primate may ultimately be features consistent with Euarchonta.
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Affiliation(s)
- Michael C Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
- Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | | | - Melody W Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, New York, USA
| | - Aleksandra Panyutina
- Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russian Federation
| | - Dionisios Youlatos
- Department of Zoology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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22
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Young MW, Dickinson E, Flaim ND, Granatosky MC. Overcoming a 'forbidden phenotype': the parrot's head supports, propels and powers tripedal locomotion. Proc Biol Sci 2022; 289:20220245. [PMID: 35582799 PMCID: PMC9115034 DOI: 10.1098/rspb.2022.0245] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
No vertebrate, living or extinct, is known to have possessed an odd number of limbs. Despite this 'forbidden phenotype', gaits that use odd numbers of limbs (e.g. tripedalism or pentapedalism) have evolved in both avian and mammalian lineages. Tripedal locomotion is commonly employed by parrots during climbing, who use their beaks as an additional support. However, it is unclear whether the beak functions simply as a stabilizing hook, or as a propulsive limb. Here, we present data on kinetics of tripedal climbing in six rosy-faced lovebirds (Agapornis roseicollis). Our findings demonstrate that parrots use cyclical tripedal gaits when climbing and the beak and hindlimbs generate comparable propulsive and tangential substrate reaction forces and power. Propulsive and tangential forces generated by the beak are of magnitudes equal to or greater than those forces generated by the forelimbs of humans and non-human primates during vertical climbing. We conclude that the feeding apparatus and neck flexors of parrots have been co-opted to function biomechanically as a propulsive third limb during vertical climbing. We hypothesize that this exaptation required substantive alterations to the neuromuscular system including enhanced force-generating capabilities of the neck flexors and modifications to locomotor central pattern generators.
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Affiliation(s)
- Melody W. Young
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Edwin Dickinson
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Nicholas D. Flaim
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
| | - Michael C. Granatosky
- Department of Anatomy, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA,Center for Biomedical Innovation, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
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23
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MacKenzie D, Watters AK, To JT, Young MW, Muratori J, Wilkoff MH, Abraham RG, Plummer MM, Zhang D. ALT Positivity in Human Cancers: Prevalence and Clinical Insights. Cancers (Basel) 2021; 13:2384. [PMID: 34069193 PMCID: PMC8156225 DOI: 10.3390/cancers13102384] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 02/08/2023] Open
Abstract
Many exciting advances in cancer-related telomere biology have been made in the past decade. Of these recent advances, great progress has also been made with respect to the Alternative Lengthening of Telomeres (ALT) pathway. Along with a better understanding of the molecular mechanism of this unique telomere maintenance pathway, many studies have also evaluated ALT activity in various cancer subtypes. We first briefly review and assess a variety of commonly used ALT biomarkers. Then, we provide both an update on ALT-positive (ALT+) tumor prevalence as well as a systematic clinical assessment of the presently studied ALT+ malignancies. Additionally, we discuss the pathogenetic alterations in ALT+ cancers, for example, the mutation status of ATRX and DAXX, and their correlations with the activation of the ALT pathway. Finally, we highlight important ALT+ clinical associations within each cancer subtype and subdivisions within, as well as their prognoses. We hope this alternative perspective will allow scientists, clinicians, and drug developers to have greater insight into the ALT cancers so that together, we may develop more efficacious treatments and improved management strategies to meet the urgent needs of cancer patients.
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Affiliation(s)
| | | | | | | | | | | | | | - Maria M. Plummer
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA; (D.M.J.); (A.K.W.); (J.T.T.); (M.W.Y.); (J.M.); (M.H.W.); (R.G.A.)
| | - Dong Zhang
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA; (D.M.J.); (A.K.W.); (J.T.T.); (M.W.Y.); (J.M.); (M.H.W.); (R.G.A.)
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24
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Affiliation(s)
| | - Youngjoo Kim
- Chemistry & PhysicsSUNY College at Old WestburyOld WestburyNY
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25
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Abstract
Ninety kilobase pairs (kb) of DNA have been isolated from the 3B region of the X chromosome of Drosophila melanogaster. Previous cytogenetic analyses have placed a gene required for rhythmic behavior (per) in this chromosomal interval. Physical characterization of a series of chromosomal rearrangements altering per locus activity indicates that DNA affecting behavioral rhythms is found in a 7.1-kb HindIII fragment. A single 4.5-kb poly(A)(+) RNA is transcribed from this DNA in wild-type pupae and adult flies. The transcript is eliminated by a per mutant that retains some rhythmic activity, but this mutant substitutes two novel transcripts, 11.5 kb and 0.9 kb. It is suggested that the new poly(A)(+) transcripts provide residual per locus activity.
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Abstract
Circadian rhythms in Drosophila are supported by a negative feedback loop, in which PERIOD (PER) and Timeless (TIM) shut down their own transcription as they translocate once a day from the cytoplasm of clock-containing cells to the nucleus. Period length is partially determined by an interval of cytoplasmic retention of the TIM and PER proteins. To study this process, we examined PER/TIM/Doubletime (DBT) physical interactions and nuclear translocation by imaging individual cultured Drosophila cells. Using live cell video microscopy and green fluorescent protein (GFP) tags, we observed dynamic patterns of stability and localization for DBT, PER, and TIM that resembled those previously found in vivo. These studies suggest that a cytoplasmic interval timer regulates nuclear translocation of these proteins. The cultured cell assay provides a potent system to study interactions among new and known genes involved in the generation of circadian behavior.
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Affiliation(s)
- L Saez
- Laboratory of Genetics, The Rockefeller University, New York, New York 10021, USA
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27
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Hawes C, Haughton AJ, Osborne JL, Roy DB, Clark SJ, Perry JN, Rothery P, Bohan DA, Brooks DR, Champion GT, Dewar AM, Heard MS, Woiwod IP, Daniels RE, Young MW, Parish AM, Scott RJ, Firbank LG, Squire GR. Responses of plants and invertebrate trophic groups to contrasting herbicide regimes in the Farm Scale Evaluations of genetically modified herbicide-tolerant crops. Philos Trans R Soc Lond B Biol Sci 2003; 358:1899-913. [PMID: 14561321 PMCID: PMC1693274 DOI: 10.1098/rstb.2003.1406] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Effects of genetically modified herbicide-tolerant (GMHT) and conventional crop management on invertebrate trophic groups (herbivores, detritivores, pollinators, predators and parasitoids) were compared in beet, maize and spring oilseed rape sites throughout the UK. These trophic groups were influenced by season, crop species and GMHT management. Many groups increased twofold to fivefold in abundance between early and late summer, and differed up to 10-fold between crop species. GMHT management superimposed relatively small (less than twofold), but consistent, shifts in plant and insect abundance, the extent and direction of these effects being dependent on the relative efficacies of comparable conventional herbicide regimes. In general, the biomass of weeds was reduced under GMHT management in beet and spring oilseed rape and increased in maize compared with conventional treatments. This change in resource availability had knock-on effects on higher trophic levels except in spring oilseed rape where herbivore resource was greatest. Herbivores, pollinators and natural enemies changed in abundance in the same directions as their resources, and detritivores increased in abundance under GMHT management across all crops. The result of the later herbicide application in GMHT treatments was a shift in resource from the herbivore food web to the detritivore food web. The Farm Scale Evaluations have demonstrated over 3 years and throughout the UK that herbivores, detritivores and many of their predators and parasitoids in arable systems are sensitive to the changes in weed communities that result from the introduction of new herbicide regimes.
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Affiliation(s)
- C Hawes
- Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, UK.
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Abstract
Mechanisms composing Drosophila's clock are conserved within the animal kingdom. To learn how such clocks influence behavioral and physiological rhythms, we determined the complement of circadian transcripts in adult Drosophila heads. High-density oligonucleotide arrays were used to collect data in the form of three 12-point time course experiments spanning a total of 6 days. Analyses of 24 hr Fourier components of the expression patterns revealed significant oscillations for approximately 400 transcripts. Based on secondary filters and experimental verifications, a subset of 158 genes showed particularly robust cycling and many oscillatory phases. Circadian expression was associated with genes involved in diverse biological processes, including learning and memory/synapse function, vision, olfaction, locomotion, detoxification, and areas of metabolism. Data collected from three different clock mutants (per(0), tim(01), and Clk(Jrk)), are consistent with both known and novel regulatory mechanisms controlling circadian transcription.
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Affiliation(s)
- A Claridge-Chang
- Laboratories of Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
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29
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Abstract
The circadian clock is a widespread cellular mechanism that underlies diverse rhythmic functions in organisms from bacteria and fungi, to plants and animals. Intense genetic analysis during recent years has uncovered many of the components and molecular mechanisms comprising these clocks. Although autoregulatory genetic networks are a consistent feature in the design of all clocks, the weight of evidence favours their independent evolutionary origins in different kingdoms.
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Affiliation(s)
- M W Young
- Laboratory of Genetics, The Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.
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30
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Abstract
Transcriptional activation by, and therefore the physiologic impact of, activated tyrosine-phosphorylated STATs (signal transducers and activators of transcription) may be negatively regulated by proteins termed PIAS (protein inhibitors of activated stats), as shown by previous experiments with mammalian cells in culture. Here, by using the genetic modifications in Drosophila, we demonstrate the in vivo functional interaction of the Drosophila homologues stat92E and a Drosophila PIAS gene (dpias). To this end we use a LOF allele and conditionally overexpressed dpias in JAK-STAT pathway mutant backgrounds. We conclude that the correct dpias/stat92E ratio is crucial for blood cell and eye development.
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Affiliation(s)
- A Betz
- Laboratories of Molecular Cell Biology and Genetics, The Rockefeller University, New York, NY 10021, USA
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31
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Abstract
Tissue-specific overexpression of the glycogen synthase kinase-3 (GSK-3) ortholog shaggy (sgg) shortens the period of the Drosophila circadian locomotor activity cycle. The short period phenotype was attributed to premature nuclear translocation of the PERIOD/TIMELESS heterodimer. Reducing SGG/GSK-3 activity lengthens period, demonstrating an intrinsic role for the kinase in circadian rhythmicity. Lowered sgg activity decreased TIMELESS phosphorylation, and it was found that GSK-3 beta specifically phosphorylates TIMELESS in vitro. Overexpression of sgg in vivo converts hypophosphorylated TIMELESS to a hyperphosphorylated protein whose electrophoretic mobility, and light and phosphatase sensitivity, are indistinguishable from the rhythmically produced hyperphosphorylated TIMELESS of wild-type flies. Our results indicate a role for SGG/GSK-3 in TIMELESS phosphorylation and in the regulated nuclear translocation of the PERIOD/TIMELESS heterodimer.
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Affiliation(s)
- S Martinek
- Laboratory of Genetics and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, NY 10021, USA
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32
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Kloss B, Rothenfluh A, Young MW, Saez L. Phosphorylation of period is influenced by cycling physical associations of double-time, period, and timeless in the Drosophila clock. Neuron 2001; 30:699-706. [PMID: 11430804 DOI: 10.1016/s0896-6273(01)00320-8] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The clock gene double-time (dbt) encodes an ortholog of casein kinase Iepsilon that promotes phosphorylation and turnover of the PERIOD protein. Whereas the period (per), timeless (tim), and dClock (dClk) genes of Drosophila each contribute cycling mRNA and protein to a circadian clock, dbt RNA and DBT protein are constitutively expressed. Robust circadian changes in DBT subcellular localization are nevertheless observed in clock-containing cells of the fly head. These localization rhythms accompany formation of protein complexes that include PER, TIM, and DBT, and reflect periodic redistribution between the nucleus and the cytoplasm. Nuclear phosphorylation of PER is strongly enhanced when TIM is removed from PER/TIM/DBT complexes. The varying associations of PER, DBT and TIM appear to determine the onset and duration of nuclear PER function within the Drosophila clock.
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Affiliation(s)
- B Kloss
- Laboratory of Genetics and, National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
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33
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Wolff CG, Schroeder DG, Young MW. Effect of improved housing on illness in children under 5 years old in northern Malawi: cross sectional study. BMJ 2001; 322:1209-12. [PMID: 11358772 PMCID: PMC31618 DOI: 10.1136/bmj.322.7296.1209] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate the effects of a Habitat for Humanity housing improvement programme in northern Malawi on the prevalence of childhood illnesses. DESIGN Household based cross sectional study. SETTING Rural communities centred near the small northern Malawi town of Ekwendeni. SUBJECTS 318 children under 5 years old. MAIN OUTCOME MEASURES Prevalence of respiratory, gastrointestinal, and malarial infections according to maternal recall, laboratory, or clinical data. RESULTS Children living in improved homes were less likely to have respiratory, gastrointestinal, or malarial illnesses (odds ratio 0.56, 95% confidence interval 0.35 to 0.91) after confounding factors were controlled for. The reductions in individual diseases were not significant. CONCLUSION Improved housing significantly reduced the burden of disease among children under 5 years old.
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Affiliation(s)
- C G Wolff
- Department of International Health, Rollins School of Public Health of Emory University, 1518 Clifton Road, Atlanta, GA 30322, USA
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34
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Young MW. The effectiveness of weekly iron and vitamin supplementation of Malawian preschool children. S Afr Med J 2001; 91:49-50. [PMID: 11236297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
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35
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Abstract
We describe a new experimental technique that allows for a tissue-specific reduction of gene activity in the Drosophila nervous system. On the basis of the observation that certain gene functions can be ubiquitously blocked by injecting double-stranded RNA into Drosophila embryos, we employed a method to interfere with an individual gene function permanently in a predetermined cell type. This was achieved by the formation of an inverted-repeat RNA sequence in the tissue of interest under control of the GAL4/UAS binary expression system. As an example, we show that inverted-repeat-mediated interference with the period gene produces a hypomorphic period phenotype. A selective decrease of period RNA appears to be a component of the cellular response.
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Affiliation(s)
- S Martinek
- Laboratory of Genetics, and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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36
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Abstract
Our sleep-wake cycles and many other approximately 24-hour rhythms of behavior and physiology persist in the absence of environmental cues. Genetic and biochemical studies have shown that such rhythms are controlled by internal molecular clocks. These are assembled from the cycling RNA and protein products of a small group of genes that are conserved throughout the animal kingdom.
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Affiliation(s)
- M W Young
- Laboratory of Genetics, The Rockefeller University, 1230 York Ave, New York, NY 10021, USA.
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37
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Abstract
Circadian (24 hour) PERIOD (PER) protein oscillation is dependent on the double-time (dbt) gene, a casein kinase Ivarepsilon homolog [1-3]. Without dbt activity, hypophosphorylated PER proteins over-accumulate, indicating that dbt is required for PER phosphorylation and turnover [3,4]. There is evidence of a similar role for casein kinase Ivarepsilon in the mammalian circadian clock [5,6]. We have isolated a new dbt allele, dbt(ar), which causes arrhythmic locomotor activity in homozygous viable adults, as well as molecular arrhythmicity, with constitutively high levels of PER proteins, and low levels of TIMELESS (TIM) proteins. Short-period mutations of per, but not of tim, restore rhythmicity to dbt(ar) flies. This suppression is accompanied by a restoration of PER protein oscillations. Our results suggest that short-period per mutations, and mutations of dbt, affect the same molecular step that controls nuclear PER turnover. We conclude that, in wild-type flies, the previously defined PER'short domain' [7,8] may regulate the activity of DBT on PER.
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Affiliation(s)
- A Rothenfluh
- Laboratory of Genetics, and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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38
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Rothenfluh A, Abodeely M, Price JL, Young MW. Isolation and analysis of six timeless alleles that cause short- or long-period circadian rhythms in Drosophila. Genetics 2000; 156:665-75. [PMID: 11014814 PMCID: PMC1461293 DOI: 10.1093/genetics/156.2.665] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In genetic screens for Drosophila mutations affecting circadian locomotion rhythms, we have isolated six new alleles of the timeless (tim) gene. Two of these mutations cause short-period rhythms of 21-22 hr in constant darkness, and four result in long-period cycles of 26-28 hr. All alleles are semidominant. Studies of the genetic interactions of some of the tim alleles with period-altering period (per) mutations indicate that these interactions are close to multiplicative; a given allele changes the period length of the genetic background by a fixed percentage, rather than by a fixed number of hours. The tim(L1) allele was studied in molecular detail. The long behavioral period of tim(L1) is reflected in a lengthened molecular oscillation of per and tim RNA and protein levels. The lengthened period is partly caused by delayed nuclear translocation of TIM(L1) protein, shown directly by immunocytochemistry and indirectly by an analysis of the phase response curve of tim(L1) flies.
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Affiliation(s)
- A Rothenfluh
- Laboratory of Genetics, and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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39
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Jin S, Martinek S, Joo WS, Wortman JR, Mirkovic N, Sali A, Yandell MD, Pavletich NP, Young MW, Levine AJ. Identification and characterization of a p53 homologue in Drosophila melanogaster. Proc Natl Acad Sci U S A 2000; 97:7301-6. [PMID: 10860994 PMCID: PMC16540 DOI: 10.1073/pnas.97.13.7301] [Citation(s) in RCA: 174] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The tumor suppressor gene p53 in mammalian cells plays a critical role in safeguarding the integrity of genome. It functions as a sequence-specific transcription factor. Upon activation by a variety of cellular stresses, p53 transactivates downstream target genes, through which it regulates cell cycle and apoptosis. However, little is known about p53 in invertebrates. Here we report the identification and characterization of a Drosophila p53 homologue gene, dp53. dp53 encodes a 385-amino acid protein with significant homology to human p53 (hp53) in the region of the DNA-binding domain, and to a lesser extent the tetramerization domain. Purified dp53 DNA-binding domain protein was shown to bind to the consensus hp53-binding site by gel mobility analysis. In transient transfection assays, expression of dp53 in Schneider cells transcriptionally activated promoters that contained consensus hp53-responsive elements. Moreover, a mutant dp53 (Arg-155 to His-155), like its hp53 counterpart mutant, exerted a dominant-negative effect on transactivation. Ectopic expression of dp53 in Drosophila eye disk caused cell death and led to a rough eye phenotype. dp53 is expressed throughout the development of Drosophila with highest expression levels in early embryogenesis, which has a maternal component. Consistent with this, dp53 RNA levels were high in the nurse cells of the ovary. It appears that p53 is structurally and functionally conserved from flies to mammals. Drosophila will provide a useful genetic system to the further study of the p53 network.
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Affiliation(s)
- S Jin
- Laboratory of Cancer Biology, Genetics, and Molecular Biophysics, Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
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40
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Abstract
The mutation timeless(UL) generates 33 hr rhythms, prolonged nuclear localization of PERIOD/TIMELESS(UL) protein complexes, and protracted derepression of period (per) and timeless (tim) transcription. Light-induced elimination of TIM(UL) from nuclear PER/TIM(UL) complexes gives strong downregulation of per and tim expression. Thus, in the absence of TIM, nuclear PER can function as a potent negative transcriptional regulator. Two additional studies support this role for PER: (1) Drosophila expressing PER that constitutively localizes to nuclei produce dominant behavioral arrhythmicity, and (2) constitutively nuclear PER represses dCLOCK/CYCLE-mediated transcription of per in cultured cells without TIM. Conversion of PER/TIM heterodimers to nuclear PER proteins appears to be required to complete transcriptional repression and terminate each circadian molecular cycle.
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Affiliation(s)
- A Rothenfluh
- Laboratory of Genetics and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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41
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Affiliation(s)
- M W Young
- Laboratory of Genetics and National Science Foundation Center for Biological Timing, The Rockefeller University, New York, NY 10021.
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42
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Abstract
A weekly iron/folate supplement was compared with a standard daily iron/folate supplement in pregnant women living in rural Malawi. Women were enrolled as they attended the local antenatal clinic, stratified by grade of anaemia and then randomized to receive either 60 mg iron/0.25 mg folate per day (n = 211) or 120 mg iron/0.50 mg folate once a week (n = 202). Supplementation was continued for a minimum of 8 weeks (10 weeks on average) and was self administered by the women at home. Initial haemoglobin values for the daily (mu = 105.7 g/l) and weekly (mu = 104.4 g/l) groups as well as final haemoglobin values (107.5 g/l and 105.6 g/l, respectively) did not differ significantly between the two groups. Haemoglobin values increased by similar levels in both groups with the subset of anaemic women increasing by an average of 6.3 g/l in the daily group (n = 70) and 5.9 g/l in the weekly group (n = 66) for all women. For compliant, anaemic women, the increases were 7.4 g/l and 6.6 g/l for the daily and weekly groups, respectively. Compliance, as indicated by self reporting and by regular counts of remaining tablets, was significantly higher in the weekly group (76% compared with 60%, P < 0.05), however compliance was identical in both groups when assessed by a stool test for elemental iron. Reported side effects were significantly reduced in the weekly group (6% compared with 17%, P < 0.05). We conclude that a weekly iron supplement given to pregnant women in rural Malawi has similar haematologic effects, and an improved side effect profile, in comparison with a standard daily supplement when administered through an existing primary healthcare programme, although both regimens are relatively unsuccessful in the reduction of anaemia prevalence during pregnancy.
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Affiliation(s)
- M W Young
- Ekwendeni Hospital, Ekwendeni, Malawi.
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43
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Affiliation(s)
- M W Young
- Laboratory of Genetics, Rockefeller University, USA
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44
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Abstract
We identified a novel regulatory loop within Drosophila's circadian clock. A screen for clock-controlled genes recovered vrille (vri), a transcription factor essential for embryonic development. vri is expressed in circadian pacemaker cells in larval and adult brains. vri RNA levels oscillate with a circadian rhythm. Cycling is directly regulated by the transcription factors dCLOCK and CYCLE, which are also required for oscillations of period and timeless RNA. Eliminating the normal vri cycle suppresses period and timeless expression and causes long-period behavioral rhythms and arrhythmicity, indicating that cycling vri is required for a functional Drosophila clock. We also show that dCLOCK and VRI independently regulate levels of a neuropeptide, pigment dispersing factor, which appears to regulate overt behavior.
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Affiliation(s)
- J Blau
- Laboratory of Genetics, The Rockefeller University, New York, New York 10021, USA
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45
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Young MW. Molecular control of circadian behavioral rhythms. Recent Prog Horm Res 1999; 54:87-94; discussion 94-5. [PMID: 10548873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Several genes have been recognized in Drosophila that regulate circadian rhythms. Homologues of these genes have now been found in mice and humans, suggesting a mechanism that is conserved throughout the animal kingdom. For some of these genes and their products, molecular oscillations are produced in certain cells of the Drosophila and mammalian brain. Two genes, period and timeless, are transcribed with a circadian rhythm that is regulated by activities derived from their encoded proteins, PER and TIM. Nuclear localization of these proteins downregulates per and tim transcription by suppressing the activities of two transcription factors, dCLOCK and dBMAL1. Cycles in this feedback regulation are promoted by events that regulate the accumulation, physical interaction, and nuclear translocation of PER and TIM proteins. PER and TIM must physically associate to enter the nucleus and their cytoplasmic interaction is delayed by a kinase encoded by the clock gene, double-time. This kinase directs PER phosphorylation, which leads to PER degradation. Effects of the kinase are blocked once PER is complexed to TIM. These interactions prolong the interval of per and tim transcription by ensuring that PER/TIM complexes from only after TIM has accumulated for several hours.
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Affiliation(s)
- M W Young
- Laboratory of Genetics, Rockefeller University, New York, New York 10021, USA
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Kidd S, Lieber T, Young MW. Ligand-induced cleavage and regulation of nuclear entry of Notch in Drosophila melanogaster embryos. Genes Dev 1998; 12:3728-40. [PMID: 9851979 PMCID: PMC317253 DOI: 10.1101/gad.12.23.3728] [Citation(s) in RCA: 193] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/1998] [Accepted: 10/20/1998] [Indexed: 11/24/2022]
Abstract
Notch, a transmembrane protein found in a wide range of organisms, is a component of a pathway that mediates cell-fate decisions that involve intercellular communication. In this paper, we show that in Drosophila melanogaster, Notch (N) is processed in a ligand-dependent fashion to generate phosphorylated, soluble intracellular derivatives. Suppressor of Hairless [Su(H)] is predominantly associated with soluble intracellular N. It has been demonstrated by others that N has access to the nucleus, and we show that when tethered directly to DNA, the cytoplasmic domain of N can activate transcription. Conversely, a viral activator fused to Su(H) can substitute for at least some N functions during embryogenesis. We suggest that one function of soluble forms of N is to bind to Su(H), and in the nucleus, to act directly as a transcriptional transactivator of the latter protein. Although N has functional nuclear localization signals, the N/Su(H) complex accumulates in the cytoplasm and on membranes suggesting that its nuclear entry is regulated. Localization studies in cultured cells and embryos suggest that Su(H) plays a role in this regulation, with the relative levels of Delta, N and Su(H) determining whether a N/Su(H) complex enters the nucleus.
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Affiliation(s)
- S Kidd
- Laboratory of Genetics, The Rockefeller University, New York, New York 10021-6399 USA
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Sangoram AM, Saez L, Antoch MP, Gekakis N, Staknis D, Whiteley A, Fruechte EM, Vitaterna MH, Shimomura K, King DP, Young MW, Weitz CJ, Takahashi JS. Mammalian circadian autoregulatory loop: a timeless ortholog and mPer1 interact and negatively regulate CLOCK-BMAL1-induced transcription. Neuron 1998; 21:1101-13. [PMID: 9856465 DOI: 10.1016/s0896-6273(00)80627-3] [Citation(s) in RCA: 284] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We report the cloning and mapping of mouse (mTim) and human (hTIM) orthologs of the Drosophila timeless (dtim) gene. The mammalian Tim genes are widely expressed in a variety of tissues; however, unlike Drosophila, mTim mRNA levels do not oscillate in the suprachiasmatic nucleus (SCN) or retina. Importantly, hTIM interacts with the Drosophila PERIOD (dPER) protein as well as the mouse PER1 and PER2 proteins in vitro. In Drosophila (S2) cells, hTIM and dPER interact and translocate into the nucleus. Finally, hTIM and mPER1 specifically inhibit CLOCK-BMAL1-induced transactivation of the mPer1 promoter. Taken together, these results demonstrate that mTim and hTIM are mammalian orthologs of timeless and provide a framework for a basic circadian autoregulatory loop in mammals.
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Affiliation(s)
- A M Sangoram
- Department of Neurobiology and Physiology and National Science Foundation, Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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Abstract
Molecular and genetic characterizations of circadian rhythms in Drosophila indicate that function of an intracellular pacemaker requires the activities of proteins encoded by three genes: period (per), timeless (tim), and doubletime (dbt). RNA from two of these genes, per and tim, is expressed with a circadian rhythm. Heterodimerization of PER and TIM proteins allows nuclear localization and suppression of further RNA synthesis by a PER/TIM complex. These protein interactions promote cyclical gene expression because heterodimers are observed only at high concentrations of per and tim RNA, separating intervals of RNA accumulation from times of PER/TIM complex activity. Light resets these molecular cycles by eliminating TIM. The product of dbt also regulates accumulation of per and tim RNA, and it may influence action of the PER/TIM complex. The recent discovery of PER homologues in mice and humans suggests that a related mechanism controls mammalian circadian behavioral rhythms.
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Affiliation(s)
- M W Young
- National Science Foundation Science and Technology Center for Biological Timing, Rockefeller University, New York, New York 10021, USA.
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Takumi T, Taguchi K, Miyake S, Sakakida Y, Takashima N, Matsubara C, Maebayashi Y, Okumura K, Takekida S, Yamamoto S, Yagita K, Yan L, Young MW, Okamura H. A light-independent oscillatory gene mPer3 in mouse SCN and OVLT. EMBO J 1998; 17:4753-9. [PMID: 9707434 PMCID: PMC1170804 DOI: 10.1093/emboj/17.16.4753] [Citation(s) in RCA: 193] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A new member of the mammalian period gene family, mPer3, was isolated and its expression pattern characterized in the mouse brain. Like mPer1, mPer2 and Drosophila period, mPer3 has a dimerization PAS domain and a cytoplasmic localization domain. mPer3 transcripts showed a clear circadian rhythm in the suprachiasmatic nucleus (SCN). Expression of mPer3 was not induced by exposure to light at any phase of the clock, distinguishing this gene from mPer1 and mPer2. Cycling expression of mPer3 was also found outside the SCN in the organum vasculosum lamina terminalis (OVLT), a potentially key region regulating rhythmic gonadotropin production and pyrogen-induced febrile phenomena. Thus, mPer3 may contribute to pacemaker functions both inside and outside the SCN.
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Affiliation(s)
- T Takumi
- Department of Anatomy and Brain Science, Kobe University School of Medicine, Chuo-ku, Kobe 650-0017, Japan
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Abstract
We have isolated three alleles of a novel Drosophila clock gene, double-time (dbt). Short- (dbtS) and long-period (dbtL) mutants alter both behavioral rhythmicity and molecular oscillations from previously identified clock genes, period and timeless. A third allele, dbtP, causes pupal lethality and eliminates circadian cycling of per and tim gene products in larvae. In dbtP mutants, PER proteins constitutively accumulate, remain hypophosphorylated, and no longer depend on TIM proteins for their accumulation. We propose that the normal function of DOUBLETIME protein is to reduce the stability and thus the level of accumulation of monomeric PER proteins. This would promote a delay between per/tim transcription and PER/TIM complex function, which is essential for molecular rhythmicity.
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Affiliation(s)
- J L Price
- Laboratory of Genetics and National Science Foundation Science and Technology Center for Biological Timing, The Rockefeller University, New York, New York 10021, USA
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