Ontology describing the anatomy of Danio rerio from a single cell to adult fish. The namespace of the ontology is zebrafish_anatomical_ontology the prefix is ZFA. Updates to ZFA are released every other month. A subset of the ZFS http://purl.obolibrary.org/obo/zfs.obo is packaged with this ontology.
Definition of the zebrafish intervertebral ligament from the ZFA: "Ligament that connects adjacent vertebra. The intervertebral ligament (IVL) connects the posterior vertebral end plate to the anterior vertebral end plate of adjacent vertebra. For example the IVL connects the posterior end plate of vertebra 14 to the anterior end plate of vertebra 15. It is typically composed of three distinct layers: the notochord sheet which is mainly type II collagen; the outer elastin layer; and a layer of type I collagen fiber bundles.(1)"
Description and comparison of mammalian and teleost intervertebral discs from ZDB-PUB-210902-3:
"Intervertebral discs (IVDs) connect consecutive vertebral bodies; their main function is mechanical, and they act as shock-absorbing cushions. Mammalian discs have an exquisite three-dimensional (3D) architecture comprised of the outer annulus fibrosus (AF) made from fibrocartilage and an inner region, the nucleus pulposus (NP). The NP is derived from the notochord; it contains chondrocyte-like cells and a gelatinous matrix composed of collagen type 2 and proteoglycans that are vital for the function of the discs and serve as a fluid-filled shock-absorbing cushion."
"In teleosts, the connections of the endplates of vertebral bodies are similar in design and function to mammalian IVD (hereafter called IVD). Centrally located vacuolated notochord cells with the same function as NP (hereafter called the NP) are surrounded by a strong composite ligament that functions like the AF (hereafter called the AF). The ligament is composed of, from inside to outside, collagen type II embedded in a matrix resembling cartilage, elastin, and collagen type 1 fiber bundles."
"In adult teleosts, vacuolated notochord cells turn into fibrous, keratinized, connective tissue (the septum and notochord strand) and extracellular vacuoles.
Disc damage and subsequent vertebral body fusion have been reported in farmed Atlantic salmon, suggesting that zebrafish could be a potential degenerative model for IVD"
Definition of the zebrafish intervertebral ligament from the ZFA: "Ligament that connects adjacent vertebra. The intervertebral ligament (IVL) connects the posterior vertebral end plate to the anterior vertebral end plate of adjacent vertebra. For example the IVL connects the posterior end plate of vertebra 14 to the anterior end plate of vertebra 15. It is typically composed of three distinct layers: the notochord sheet which is mainly type II collagen; the outer elastin layer; and a layer of type I collagen fiber bundles.(1)"
Description and comparison of mammalian and teleost intervertebral discs from ZDB-PUB-210902-3: "Intervertebral discs (IVDs) connect consecutive vertebral bodies; their main function is mechanical, and they act as shock-absorbing cushions. Mammalian discs have an exquisite three-dimensional (3D) architecture comprised of the outer annulus fibrosus (AF) made from fibrocartilage and an inner region, the nucleus pulposus (NP). The NP is derived from the notochord; it contains chondrocyte-like cells and a gelatinous matrix composed of collagen type 2 and proteoglycans that are vital for the function of the discs and serve as a fluid-filled shock-absorbing cushion." "In teleosts, the connections of the endplates of vertebral bodies are similar in design and function to mammalian IVD (hereafter called IVD). Centrally located vacuolated notochord cells with the same function as NP (hereafter called the NP) are surrounded by a strong composite ligament that functions like the AF (hereafter called the AF). The ligament is composed of, from inside to outside, collagen type II embedded in a matrix resembling cartilage, elastin, and collagen type 1 fiber bundles." "In adult teleosts, vacuolated notochord cells turn into fibrous, keratinized, connective tissue (the septum and notochord strand) and extracellular vacuoles. Disc damage and subsequent vertebral body fusion have been reported in farmed Atlantic salmon, suggesting that zebrafish could be a potential degenerative model for IVD"
This 2009 publication describes the development of the zebrafish intervertebral disc: https://zfin.org/ZDB-PUB-090407-22
Examples: Illustration in panel A https://zfin.org/ZDB-IMAGE-210327-79 Figure: https://zfin.org/ZDB-IMAGE-230529-54