1
|
Anthwal N, Hall RP, de la Rosa Hernandez FA, Koger M, Yohe LR, Hedrick BP, Davies KTJ, Mutumi GL, Roseman CC, Dumont ER, Dávalos LM, Rossiter SJ, Sadier A, Sears KE. Cochlea development shapes bat sensory system evolution. Anat Rec (Hoboken) 2023. [PMID: 37994725 DOI: 10.1002/ar.25353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 11/01/2023] [Accepted: 11/08/2023] [Indexed: 11/24/2023]
Abstract
Sensory organs must develop alongside the skull within which they are largely encased, and this relationship can manifest as the skull constraining the organs, organs constraining the skull, or organs constraining one another in relative size. How this interplay between sensory organs and the developing skull plays out during the evolution of sensory diversity; however, remains unknown. Here, we examine the developmental sequence of the cochlea, the organ responsible for hearing and echolocation, in species with distinct diet and echolocation types within the ecologically diverse bat super-family Noctilionoidea. We found the size and shape of the cochlea largely correlates with skull size, with exceptions of Pteronotus parnellii, whose high duty cycle echolocation (nearly constant emission of sound pulses during their echolocation process allowing for detailed information gathering, also called constant frequency echolocation) corresponds to a larger cochlear and basal turn, and Monophyllus redmani, a small-bodied nectarivorous bat, for which interactions with other sensory organs restrict cochlea size. Our findings support the existence of developmental constraints, suggesting that both developmental and anatomical factors may act synergistically during the development of sensory systems in noctilionoid bats.
Collapse
Affiliation(s)
- Neal Anthwal
- King's College London, Centre for Craniofacial and Regenerative Biology, London, UK
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, USA
| | - Ronald P Hall
- Department of Life and Environment Sciences, University of California Merced, Merced, California, USA
| | | | - Michael Koger
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, USA
| | - Laurel R Yohe
- Department of Bioinformatics and Genomics, University of North Carolina Charlotte, Charlotte, North Carolina, USA
| | - Brandon P Hedrick
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Kalina T J Davies
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - Gregory L Mutumi
- Department of Life and Environment Sciences, University of California Merced, Merced, California, USA
| | - Charles C Roseman
- Department of Evolution, Ecology, and Behavior, University of Illinois at Urbana-Champaign, Urbana-Champaign, Illinois, USA
| | - Elizabeth R Dumont
- Department of Life and Environment Sciences, University of California Merced, Merced, California, USA
| | - Liliana M Dávalos
- Department of Ecology and Evolution and Consortium for Inter-Disciplinary Environmental Research, Stony Brook University, Stony Brook, New York, USA
| | - Stephen J Rossiter
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - Alexa Sadier
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, USA
| | - Karen E Sears
- Department of Ecology and Evolutionary Biology, University of California Los Angeles, Los Angeles, California, USA
- Department of Molecular, Cellular, and Developmental Biology, University of California Los Angeles, Los Angeles, California, USA
| |
Collapse
|
2
|
Liu W, Atturo F, Aldaya R, Santi P, Cureoglu S, Obwegeser S, Glueckert R, Pfaller K, Schrott-Fischer A, Rask-Andersen H. Macromolecular organization and fine structure of the human basilar membrane - RELEVANCE for cochlear implantation. Cell Tissue Res 2015; 360:245-62. [PMID: 25663274 PMCID: PMC4412841 DOI: 10.1007/s00441-014-2098-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 12/16/2014] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Cochlear micromechanics and frequency tuning depend on the macromolecular organization of the basilar membrane (BM), which is still unclear in man. Novel techniques in cochlear implantation (CI) motivate further analyses of the BM. MATERIALS AND METHODS Normal cochleae from patients undergoing removal of life-threatening petro-clival meningioma and an autopsy specimen from a normal human were used. Laser-confocal microscopy, high resolution scanning (SEM) and transmission electron microscopy (TEM) were carried out in combination. In addition, one human temporal bone was decellularized and investigated by SEM. RESULTS The human BM consisted in four separate layers: (1) epithelial basement membrane positive for laminin-β2 and collagen IV, (2) BM "proper" composed of radial fibers expressing collagen II and XI, (3) layer of collagen IV and (4) tympanic covering layer (TCL) expressing collagen IV, fibronectin and integrin. BM thickness varied both radially and longitudinally (mean 0.55-1.16 μm). BM was thinnest near the OHC region and laterally. CONCLUSIONS There are several important similarities and differences between the morphology of the BM in humans and animals. Unlike in animals, it does not contain a distinct pars tecta (arcuate) and pectinata. Its width increases and thickness decreases as it travels apically in the cochlea. Findings show that the human BM is thinnest and probably most vibration-sensitive at the outer pillar feet/Deiter cells at the OHCs. The inner pillar and IHCs seem situated on a fairly rigid part of the BM. The gradient design of the BM suggests that its vulnerability increases apical wards when performing hearing preservation CI surgery.
Collapse
Affiliation(s)
- Wei Liu
- Department of Surgical Sciences, Head and Neck Surgery, section of Otolaryngology, Uppsala University Hospital, 751 85, Uppsala, Sweden,
| | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Abstract
The role of the cochlea is to transduce complex sound waves into electrical neural activity in the auditory nerve. Hair cells of the organ of Corti are the sensory cells of hearing. The inner hair cells perform the transduction and initiate the depolarization of the spiral ganglion neurons. The outer hair cells are accessory sensory cells that enhance the sensitivity and selectivity of the cochlea. Neural feedback loops that bring efferent signals to the outer hair cells assist in sharpening and amplifying the signals. The stria vascularis generates the endocochlear potential and maintains the ionic composition of the endolymph, the fluid in which the apical surface of the hair cells is bathed. The mechanical characteristics of the basilar membrane and its related structures further enhance the frequency selectivity of the auditory transduction mechanism. The tectorial membrane is an extracellular matrix, which provides mass loading on top of the organ of Corti, facilitating deflection of the stereocilia. This review deals with the structure of the normal mature mammalian cochlea and includes recent data on the molecular organization of the main cell types within the cochlea.
Collapse
Affiliation(s)
- Yehoash Raphael
- Kresge Hearing Research Institute, The University of Michigan, MSRB 3, Rm 9303, 1150 W. Medical Center Drive, Ann Arbor, MI 48109-0648, USA.
| | | |
Collapse
|
5
|
Kössl M, Vater M. The cochlear frequency map of the mustache bat, Pteronotus parnellii. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1985; 157:687-97. [PMID: 3837108 DOI: 10.1007/bf01351362] [Citation(s) in RCA: 112] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The frequency-place map of the cochlea of mustache bats was constructed by the analysis of HRP-transport patterns in spiral ganglion cells following iontophoretic tracer injections into cochlear nucleus regions responsive to different frequencies. The cochlea consists of 5 half turns (total length 14.3 mm) and the representation of certain frequency bands can be assigned to specific cochlear regions: The broad high frequency range between 70 and 111 kHz is represented in the most basal half turn within only 3.2 mm. This region is terminated apically by a distinct narrowing of the scala vestibuli that coincides with a pronounced increase in basilar membrane (BM) thickness. The narrow intermediate frequency range between 54 and 70 kHz is expanded onto 50% of cochlear length between 4.0 and 11.1 mm distance from apex. The frequency range around 60 kHz, where the tuning characteristics of the auditory system are exceptionally sharp, is located in the center of this expanded BM-region in the second half turn within a maximum of innervation density. These data can account for the vast overrepresentation of neurons sharply tuned to about 60 kHz at central stations of the auditory pathway. In the cochlear region just basal to the innervation maximum, where label from injections at 66 and 70 kHz was found, a number of morphological specializations coincide: the BM is maximally thickened, innervation density is low, the spiral ligament is locally enlarged, and the 'thick lining', a dense covering of the scala tympani throughout the basal halfturn, suddenly disappears. Low frequencies up to 54 kHz are represented within the apical half turns over a 4 mm span of the basilar membrane. The data are compared to the cochlea of horseshoe bats and the possible functional role of the morphological discontinuities for sharp tuning and the generation of otoacoustic emissions is discussed.
Collapse
|