1
|
Kang H, Liu Q, Seim I, Zhang W, Li H, Gao H, Lin W, Lin M, Zhang P, Zhang Y, Gao H, Wang Y, Qin Y, Liu M, Dong L, Yang Z, Zhang Y, Han L, Fan G, Li S. A genome and single-nucleus cerebral cortex transcriptome atlas of the short-finned pilot whale Globicephala macrorhynchus. Mol Ecol Resour 2023. [PMID: 36826393 DOI: 10.1111/1755-0998.13775] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 02/09/2023] [Accepted: 02/22/2023] [Indexed: 02/25/2023]
Abstract
Cetaceans (dolphins, whales, and porpoises) have large and anatomically sophisticated brains. To expand our understanding of the cellular makeup of cetacean brains and the similarities and divergence between the brains of cetaceans and terrestrial mammals, we report a short-finned pilot whale (Globicephala macrorhynchus) single-nucleus transcriptome atlas. To achieve this goal, we assembled a chromosome-scale reference genome spanning 2.25 Gb on 22 chromosomes and profiled the gene expression of five major anatomical cortical regions of the short-finned pilot whale by single-nucleus RNA-sequencing (snRNA-seq). We identified six major cell lineages in the cerebral cortex (excitatory neurons, inhibitory neurons, oligodendrocytes, oligodendrocyte precursor cells, astrocytes, and endothelial cells), eight molecularly distinct subclusters of excitatory neurons, and four subclusters of inhibitory neurons. Finally, a comparison of snRNA-seq data from the short-finned pilot whale, human, and rhesus macaque revealed a broadly conserved cellular makeup of brain cell types. Our study provides genomic resources and molecular insights into cetacean brain evolution.
Collapse
Affiliation(s)
- Hui Kang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Qun Liu
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, Qingdao, China.,Department of Biology, University of Copenhagen, Copenhagen, Denmark.,Qingdao Key Laboratory of Marine Genomics, BGI-Qingdao, Qingdao, China
| | - Inge Seim
- Integrative Biology Laboratory, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Wenwei Zhang
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Hanbo Li
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,Lars Bolund Institute of Regenerative Medicine, Qingdao-Europe Advanced Institute for Life Sciences, BGI-Qingdao, Qingdao, China
| | - Haiyu Gao
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wenzhi Lin
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Mingli Lin
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Peijun Zhang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | | | | | - Yang Wang
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China
| | - Yating Qin
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China
| | - Mingming Liu
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Lijun Dong
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | - Zixin Yang
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| | | | - Lei Han
- State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Guangyi Fan
- BGI-Qingdao, BGI-Shenzhen, Qingdao, China.,State Key Laboratory of Agricultural Genomics, BGI-Shenzhen, Shenzhen, China
| | - Songhai Li
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, China
| |
Collapse
|
2
|
Chang YH, Sheftel BI, Jensen B. Anatomy of the heart with the highest heart rate. J Anat 2022; 241:173-190. [PMID: 35128670 PMCID: PMC9178362 DOI: 10.1111/joa.13640] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/29/2021] [Accepted: 01/24/2022] [Indexed: 11/26/2022] Open
Abstract
Shrews occupy the lower extreme of the seven orders of magnitude mammals range in size. Their hearts are large relative to body weight and heart rate can exceed a thousand beats a minute. It is not known whether traits typical of mammal hearts scale to these extremes. We assessed the heart of three species of shrew (genus Sorex) following the sequential segmental analysis developed for human hearts. Using micro‐computed tomography, we describe the overall structure and find, in agreement with previous studies, a large and elongate ventricle. The atrial and ventricular septums and the atrioventricular (AV) and arterial valves are typically mammalian. The ventricular walls comprise mostly compact myocardium and especially the right ventricle has few trabeculations on the luminal side. A developmental process of compaction is thought to reduce trabeculations in mammals, but in embryonic shrews the volume of trabeculations increase for every gestational stage, only slower than the compact volume. By expression of Hcn4, we identify a sinus node and an AV conduction axis which is continuous with the ventricular septal crest. Outstanding traits include pulmonary venous sleeve myocardium that reaches farther into the lungs than in any other mammals. Typical proportions of coronary arteries‐to‐aorta do not scale and the shrew coronary arteries are proportionally enormous, presumably to avoid the high resistance to blood flow of narrow vessels. In conclusion, most cardiac traits do scale to the miniscule shrews. The shrew heart, nevertheless, stands out by its relative size, elongation, proportionally large coronary vessels, and extent of pulmonary venous myocardium.
Collapse
Affiliation(s)
- Yun Hee Chang
- Department of Medical Biology University of Amsterdam, Amsterdam, Cardiovascular Sciences, Amsterdam UMC Amsterdam The Netherlands
| | - Boris I. Sheftel
- A.N. Severtsov Institute of Ecology and Evolution RAS (Russian Academy of Sciences) Moscow Russian Federation
| | - Bjarke Jensen
- Department of Medical Biology University of Amsterdam, Amsterdam, Cardiovascular Sciences, Amsterdam UMC Amsterdam The Netherlands
| |
Collapse
|
3
|
Latorre R, Graïc JM, Raverty SA, Soria F, Cozzi B, López-Albors O. The Heart of the Killer Whale: Description of a Plastinated Specimen and Review of the Available Literature. Animals (Basel) 2022; 12:ani12030347. [PMID: 35158671 PMCID: PMC8833494 DOI: 10.3390/ani12030347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 02/06/2023] Open
Abstract
Simple Summary The killer whale (Orcinus orca, Linnaeus, 1958) is an odontocete and is the largest member of the family Delphinidae. Free-ranging animals are capable of considerable physical efforts, either as acute bursts or sustained speeds during foraging, diving or protracted long-distance migrations. In this article, the morphology of a plastinated heart of a killer whale and functional adaptations of the gross anatomy in the context of a variety of physiologic demands is evaluated. The four chambers, their content, respective openings and communicating passages are defined based on a specimen used for plastination and thus available for extended and detailed anatomic studies. Abstract The killer whale (Orcinus orca, Linnaeus, 1958) is the largest extant delphinid. Despite its worldwide distribution in the wild and in dolphinariums, its anatomy remains relatively poorly described. In the present study, we describe the detailed morphology of a plastinated killer whale heart. The gross description of the arteries and veins reaching the organ and its coronary vessels are reported. Additional endoscopy and CT (computed tomography) scanning were performed to provide extensive measurements of its parts. In many aspects, the killer whale heart conformed to other delphinid heart descriptions, including position, relative size and shape and specific features such as extensive papillary muscles, trabecular endocardium and trabecula septomarginalis. These characteristics are representative of the delphinid family, suggesting that its functions and capacities are similar to that of other, smaller, dolphins and help understand the conditions in which these predators exert their remarkable physical performance necessary for their survival.
Collapse
Affiliation(s)
- Rafael Latorre
- Department of Anatomy and Comparative Pathology, University of Murcia, 30100 Murcia, Spain; (R.L.); (O.L.-A.)
| | - Jean-Marie Graïc
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy;
- Correspondence:
| | - Stephen A. Raverty
- Animal Health Center, British Columbia Ministry of Agriculture, Abbotsford, BC V3G 2M3, Canada;
| | - Federico Soria
- Department of Endoscopy-Endourology, Jesús Usón Minimally Invasive Surgery Centre, 10071 Cáceres, Spain;
| | - Bruno Cozzi
- Department of Comparative Biomedicine and Food Science, University of Padova, 35020 Padova, Italy;
| | - Octavio López-Albors
- Department of Anatomy and Comparative Pathology, University of Murcia, 30100 Murcia, Spain; (R.L.); (O.L.-A.)
| |
Collapse
|
4
|
Abstract
In the 1950s, Arthur C. Guyton removed the heart from its pedestal in cardiovascular physiology by arguing that cardiac output is primarily regulated by the peripheral vasculature. This is counterintuitive, as modulating heart rate would appear to be the most obvious means of regulating cardiac output. In this Review, we visit recent and classic advances in comparative physiology in light of this concept. Although most vertebrates increase heart rate when oxygen demands rise (e.g. during activity or warming), experimental evidence suggests that this tachycardia is neither necessary nor sufficient to drive a change in cardiac output (i.e. systemic blood flow, Q̇ sys) under most circumstances. Instead, Q̇ sys is determined by the interplay between vascular conductance (resistance) and capacitance (which is mainly determined by the venous circulation), with a limited and variable contribution from heart function (myocardial inotropy). This pattern prevails across vertebrates; however, we also highlight the unique adaptations that have evolved in certain vertebrate groups to regulate venous return during diving bradycardia (i.e. inferior caval sphincters in diving mammals and atrial smooth muscle in turtles). Going forward, future investigation of cardiovascular responses to altered metabolic rate should pay equal consideration to the factors influencing venous return and cardiac filling as to the factors dictating cardiac function and heart rate.
Collapse
Affiliation(s)
- William Joyce
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark .,Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON K1N 6N5, Canada
| | - Tobias Wang
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark
| |
Collapse
|
5
|
Joyce W, Crossley DA, Wang T, Jensen B. Smooth Muscle in Cardiac Chambers is Common in Turtles and Extensive in the Emydid Turtle, Trachemys scripta. Anat Rec (Hoboken) 2019; 303:1327-1336. [PMID: 31509333 PMCID: PMC7216914 DOI: 10.1002/ar.24257] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/24/2019] [Accepted: 06/28/2019] [Indexed: 02/03/2023]
Abstract
A prominent layer of smooth muscle lining the luminal side of the atria of freshwater turtles (Emydidae) was described more than a century ago. We recently demonstrated that this smooth muscle provides a previously unrecognized mechanism to change cardiac output in the emydid red-eared slider (Trachemys scripta) that possibly contributes to their tremendous diving capacity. The purpose of the present immunohistochemical study was firstly to screen major groups of vertebrates for the presence of cardiac smooth muscle. Secondly, we investigated the phylogenetic distribution of cardiac smooth muscle within the turtle order (Testudines), including terrestrial and aquatic species. Atrial smooth muscle was not detected in a range of vertebrates, including Xenopus laevis, Alligator mississippiensis, and Caiman crocodilus, all of which have pronounced diving capacities. However, we confirmed earlier reports that traces of smooth muscle are found in human atrial tissue. Only within the turtles (eight species) was there substantial amounts of nonvascular smooth muscle in the heart. This amount was greatest in the atria, while the amount in proportion to cardiac muscle was greater in the sinus venosus than in other chambers. T. scripta had more smooth muscle in the sinus venosus and atria than the other turtles. In some specimens, there was some smooth muscle in the ventricle and the pulmonary vein. Our study demonstrates that cardiac smooth muscle likely appeared early in turtle evolution and has become extensive within the Emydidae family, possibly in association with diving. Across other tetrapod clades, cardiac smooth muscle might not associate with diving. Anat Rec, 303:1327-1336, 2020. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association for Anatomy.
Collapse
Affiliation(s)
- William Joyce
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark
| | - Dane A Crossley
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam 1105AZ, the Netherlands
| | - Tobias Wang
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
| | - Bjarke Jensen
- Department of Medical Biology, University Medical Center Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
6
|
Joyce W, Axelsson M, Wang T. Contraction of atrial smooth muscle reduces cardiac output in perfused turtle hearts. ACTA ACUST UNITED AC 2019; 222:jeb.199828. [PMID: 30787139 DOI: 10.1242/jeb.199828] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 02/18/2019] [Indexed: 11/20/2022]
Abstract
Unusual undulations in resting tension (tonus waves) were described in isolated atria from freshwater turtles more than a century ago. These tonus waves were soon after married with the histological demonstration of a rich layer of smooth muscle on the luminal side of the atrial wall. Research thereafter waned and the functional significance of this smooth muscle has remained obscure. Here, we provide evidence that contraction of the smooth muscle in the atria may be able to change cardiac output in turtle hearts. In in situ perfused hearts of the red-eared slider turtle (Trachemys scripta elegans), we demonstrated that activation of smooth muscle contraction with histamine (100 nmol kg-1 bolus injected into perfusate) reduced cardiac output by decreasing stroke volume (>50% decrease in both parameters). Conversely, inhibition of smooth muscle contraction with wortmannin (10 µmol l-1 perfusion) approximately doubled baseline stroke volume and cardiac output. We suggest that atrial smooth muscle provides a unique mechanism to control cardiac filling that could be involved in the regulation of stroke volume during diving.
Collapse
Affiliation(s)
- William Joyce
- Department of Bioscience, Section for Zoophysiology, Aarhus University, 8000 Aarhus C, Denmark
| | - Michael Axelsson
- Department of Biological and Environmental Sciences, University of Gothenburg, SE 405 30 Gothenburg, Sweden
| | - Tobias Wang
- Department of Bioscience, Section for Zoophysiology, Aarhus University, 8000 Aarhus C, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus C, Denmark
| |
Collapse
|