Editing Cartilage (section)

=== Development ===
{{Main|Chondrogenesis}}

In [[embryogenesis]], the [[skeletal]] system is derived from the [[mesoderm]] germ layer. Chondrification (also known as chondrogenesis) is the process by which cartilage is formed from condensed [[mesenchyme]] tissue, which differentiates into [[chondroblast]]s and begins secreting the molecules ([[aggrecan]] and collagen type&nbsp;II) that form the extracellular matrix. In all vertebrates, cartilage is the main skeletal tissue in early ontogenetic stages;<ref>{{cite journal |last1=Buffrénil |first1=Vivian de |last2=Quilhac |first2=Alexandra |title=An Overview of the Embryonic Development of the Bony Skeleton |journal=Vertebrate Skeletal Histology and Paleohistology |date=2021 |pages=29–38 |doi=10.1201/9781351189590-2 |url=https://www.taylorfrancis.com/chapters/edit/10.1201/9781351189590-2/overview-embryonic-development-bony-skeleton-vivian-de-buffr%C3%A9nil-alexandra-quilhac |publisher=CRC Press|isbn=9781351189590 |s2cid=236422314 }}</ref><ref>{{cite journal |last1=Quilhac |first1=Alexandra |title=An Overview of Cartilage Histology |journal=Vertebrate Skeletal Histology and Paleohistology |date=2021 |pages=123–146 |doi=10.1201/9781351189590-7 |url=https://www.taylorfrancis.com/chapters/edit/10.1201/9781351189590-7/overview-cartilage-histology-alexandra-quilhac |publisher=CRC Press|isbn=9781351189590 |s2cid=236413810 }}</ref> in osteichthyans, many cartilaginous elements subsequently ossify through [[endochondral]] and perichondral ossification.<ref>{{cite journal |last1=Cervantes-Diaz |first1=Fret |last2=Contreras |first2=Pedro |last3=Marcellini |first3=Sylvain |title=Evolutionary origin of endochondral ossification: the transdifferentiation hypothesis |journal=Development Genes and Evolution |date=March 2017 |volume=227 |issue=2 |pages=121–127 |doi=10.1007/s00427-016-0567-y|pmid=27909803 |s2cid=21024809 }}</ref>

Following the initial chondrification that occurs during embryogenesis, cartilage growth consists mostly of the maturing of immature cartilage to a more mature state. The division of cells within cartilage occurs very slowly, and thus growth in cartilage is usually not based on an increase in size or mass of the cartilage itself.<ref>{{cite journal | vauthors = Asanbaeva A, Masuda K, Thonar EJ, Klisch SM, Sah RL | title = Cartilage growth and remodeling: modulation of balance between proteoglycan and collagen network in vitro with beta-aminopropionitrile | journal = Osteoarthritis and Cartilage | volume = 16 | issue = 1 | pages = 1–11 | date = January 2008 | pmid = 17631390 | doi = 10.1016/j.joca.2007.05.019 | url = https://digitalcommons.calpoly.edu/cgi/viewcontent.cgi?article=1015&context=meng_fac | doi-access = free }}</ref> It has been identified that non-coding RNAs (e.g. miRNAs and long non-coding RNAs) as the most important epigenetic modulators can affect the chondrogenesis. This also justifies the non-coding RNAs' contribution in various cartilage-dependent pathological conditions such as arthritis, and so on.<ref>{{cite journal | vauthors = Razmara E, Bitaraf A, Yousefi H, Nguyen TH, Garshasbi M, Cho WC, Babashah S | title = Non-Coding RNAs in Cartilage Development: An Updated Review | journal = International Journal of Molecular Sciences | volume = 20 | issue = 18 | pages = 4475 | date = September 2019 | pmid = 31514268 | pmc = 6769748 | doi = 10.3390/ijms20184475 | doi-access = free }}</ref>