This Key Event Relationship is licensed under the Creative Commons BY-SA license. This license allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, so long as attribution is given to the creator. The license allows for commercial use. If you remix, adapt, or build upon the material, you must license the modified material under identical terms.

Relationship: 2685

Title

A descriptive phrase which clearly defines the two KEs being considered and the sequential relationship between them (i.e., which is upstream, and which is downstream). More help

Decrease, sox9 expression leads to Smaller and morphologically distorted facial cartilage structures

Upstream event
The causing Key Event (KE) in a Key Event Relationship (KER). More help
Downstream event
The responding Key Event (KE) in a Key Event Relationship (KER). More help

Key Event Relationship Overview

The utility of AOPs for regulatory application is defined, to a large extent, by the confidence and precision with which they facilitate extrapolation of data measured at low levels of biological organisation to predicted outcomes at higher levels of organisation and the extent to which they can link biological effect measurements to their specific causes.Within the AOP framework, the predictive relationships that facilitate extrapolation are represented by the KERs. Consequently, the overall WoE for an AOP is a reflection in part, of the level of confidence in the underlying series of KERs it encompasses. Therefore, describing the KERs in an AOP involves assembling and organising the types of information and evidence that defines the scientific basis for inferring the probable change in, or state of, a downstream KE from the known or measured state of an upstream KE. More help

AOPs Referencing Relationship

AOP Name Adjacency Weight of Evidence Quantitative Understanding Point of Contact Author Status OECD Status
Aryl hydrocarbon receptor activation leading to early life stage mortality via sox9 repression induced impeded craniofacial development adjacent High Low Prarthana Shankar (send email) Under development: Not open for comment. Do not cite Under Review

Taxonomic Applicability

Latin or common names of a species or broader taxonomic grouping (e.g., class, order, family) that help to define the biological applicability domain of the KER.In general, this will be dictated by the more restrictive of the two KEs being linked together by the KER.  More help
Term Scientific Term Evidence Link
zebrafish Danio rerio High NCBI
rat Rattus norvegicus High NCBI
chicken Gallus gallus High NCBI
mouse Mus musculus High NCBI
Sebastiscus marmoratus Sebastiscus marmoratus High NCBI

Sex Applicability

An indication of the the relevant sex for this KER. More help
Sex Evidence
Unspecific High

Life Stage Applicability

An indication of the the relevant life stage(s) for this KER.  More help
Term Evidence
Embryo High
Development High

Key Event Relationship Description

Provides a concise overview of the information given below as well as addressing details that aren’t inherent in the description of the KEs themselves. More help
  • Sox9 is an important transcriptional regulator that has been implicated in several functions including craniofacial development, specifically via chondrogenesis or the formation of cartilage structure (Lefebvre and Dvir-Ginzberg 2017).
  • Additionally, exposure of different animals to relevant environmental pollutants leads to a significant decrease of sox9 expression (Garcia et al., 2017; Shi et al., 2017; Tussellino et al., 2016).
  • This KER provides lines of evidence linking the sox9 repression to alterations in craniofacial development and function.

Evidence Collection Strategy

Include a description of the approach for identification and assembly of the evidence base for the KER. For evidence identification, include, for example, a description of the sources and dates of information consulted including expert knowledge, databases searched and associated search terms/strings.  Include also a description of study screening criteria and methodology, study quality assessment considerations, the data extraction strategy and links to any repositories/databases of relevant references.Tabular summaries and links to relevant supporting documentation are encouraged, wherever possible. More help

Evidence Supporting this KER

Addresses the scientific evidence supporting KERs in an AOP setting the stage for overall assessment of the AOP. More help

KER 2685 concordance table: https://aopwiki.org/system/dragonfly/production/2022/10/20/71wqxtrj9g_Concordance_Table_sox9_to_craniofacial_clean.pdf

Biological Plausibility
Addresses the biological rationale for a connection between KEupstream and KEdownstream.  This field can also incorporate additional mechanistic details that help inform the relationship between KEs, this is useful when it is not practical/pragmatic to represent these details as separate KEs due to the difficulty or relative infrequency with which it is likely to be measured.   More help
  • Compelling biological plausibility evidence comes from studies in multiple species showing the spatiotemporal expression of sox9 in the developing cartilage structures of the jaw.
    • In mice, sox9 mRNA is widely expressed in the condylar anlage and Meckel’s cartilage (Shibata et al. 2006), and the sox9 protein in the tissue layer of secondary cartilage (Hirouchi et al., 2018; Zhang et al., 2013) suggesting roles of sox9 in chondrogenesis. Additionally, sox9 is expressed widely during palatogenesis (Nie 2006; Watanabe et al., 2016), and is also found in the temporomandibular joint of developing mice (TMJ) (Wang et al., 2011). There is a some evidence for sox9 being expressed in the condyle cartilage, as well as the proliferative layer and in the chondrocytes of developing rats (Al-Dujaili et al., 2018; Rabie and Hägg 2002).
    • Sox9 is expressed within the developing chondrocytes of rabbits (Huang et al., 2015).
    • Sox9 is expressed in the different regions of the jaw cartilage structure of developing chickens (Hu et al., 2008), duck, and quail  (Eames and Schneider 2008).
    • In zebrafish, sox9b has spatiotemporal expression patterns in and around perichondrial cells (Burns et al., 2015), and generally in the lower jaw region of developing sox9b reporter zebrafish (Garcia et al., 2017) (Burns et al., 2016). Sox9 expression has been detected in the dentition of atlantic salmon as well (Huysseune et al., 2008).
    • Compared to mice, sox9 expression was identified earlier in the cranial analgen of opposum embryos demonstrating species-specific sox9 expression spatiotemporal patterns (Wakamatsu et al., 2014).
  • Few studies have found evidence for relationships between sox9 and molecular signaling pathways that are important for normal development of the craniofacial region. The lines of evidence provide some mechanisms by which sox9 can be involved when disruption of craniofacial cartilage takes place.
    • Fertilized chicken eggs infected with retroviruses coding BMP had sox9 expression induced in different regions of the cartilage structure (Hu et al., 2008).
    • Exogenous BMP4 added to mouse mandibular explants leads to induction of sox9 expression within 24 hours (Semba et al., 2000). Similarly rat organ cultures exposed to BMP7 for eight days had significantly increased sox9 expression as well as more bone and cartilage, as well as an induction of chondrocyte proliferation and differentiation (Cowan et al., 2006).
    • In mouse and chicken in vitro culture systems, addition of BMP induced chondrogenesis, while epidermal growth factor (EGF) repressed both chondrogenesis and also led to sox9 repression (Nonaka et al., 1999).
    • Noggin-soaked beads inserted into stage 15 or stage 20 chicken embryos had increased sox9 expression in the maxillary mesenchyme which was associated with ectopic cartilage growth in the stage 15 embryos, and loss of bones in the stage 20 animals (Celá et al., 2016).
    • Fibroblast growth factors (FGFs) which play a fundamental role in cartilage formation were added to chicken pluripotent mesenchymal cells which led to both sox repression as well as depression of cartilage matrix production (Bobick et al., 2007). In the case of one rat study, FGF10 electroporated via an expression vector increased both sox9 expression as well as the size of the Meckel’s cartilage (Terao et al., 2011).
    • Condylar cartilage explants cultured with a notch signal inhibitor had sox9 expression increased as well as a decrease of proliferation as measured by cyclic B1 expression (Serrano et al., 2014).
    • Wnt signaling inhibited by dickkopf-1 in chicken embryos had sox9 expression downregulated, in addition to defects of the maxilla and hypoplasia of the premaxilla and palatine bones (Shimomura et al., 2019).
Uncertainties and Inconsistencies
Addresses inconsistencies or uncertainties in the relationship including the identification of experimental details that may explain apparent deviations from the expected patterns of concordance. More help
  • Few studies have showed an opposite relationship between sox9 expression and the size of cartilage structures.
    • Conditional knockout of setdb1 (histone methyltransferase) specifically in the murine Meckel’s cartilage led to and enlargement of the cartilage structure as well as the proliferation of chondrocytes, however, sox9 expression was significantly repressed (Yahiro et al., 2017).
    • Experimental unilateral anterior crossbite created in rats led to decreased ratio of the hypertrophic cartilage layer in the experiment group, which was evidence for obvious cartilage degradation. This was accompanied by induction of sox9 expression (Zhang et al., 2013b).
  • One recent zebrafish study using the CRISPR-Cas9 tool, demonstrated that sox9a but not sox9b was required for normal cartilage development (Lin et al., 2021). This is inconsistent with all previous research showing the importance of both sox9a and sox9b for cartilage development in zebrafish.

Known modulating factors

This table captures specific information on the MF, its properties, how it affects the KER and respective references.1.) What is the modulating factor? Name the factor for which solid evidence exists that it influences this KER. Examples: age, sex, genotype, diet 2.) Details of this modulating factor. Specify which features of this MF are relevant for this KER. Examples: a specific age range or a specific biological age (defined by...); a specific gene mutation or variant, a specific nutrient (deficit or surplus); a sex-specific homone; a certain threshold value (e.g. serum levels of a chemical above...) 3.) Description of how this modulating factor affects this KER. Describe the provable modification of the KER (also quantitatively, if known). Examples: increase or decrease of the magnitude of effect (by a factor of...); change of the time-course of the effect (onset delay by...); alteration of the probability of the effect; increase or decrease of the sensitivity of the downstream effect (by a factor of...) 4.) Provision of supporting scientific evidence for an effect of this MF on this KER. Give a list of references.  More help
Response-response Relationship
Provides sources of data that define the response-response relationships between the KEs.  More help
Time-scale
Information regarding the approximate time-scale of the changes in KEdownstream relative to changes in KEupstream (i.e., do effects on KEdownstream lag those on KEupstream by seconds, minutes, hours, or days?). More help
Known Feedforward/Feedback loops influencing this KER
Define whether there are known positive or negative feedback mechanisms involved and what is understood about their time-course and homeostatic limits. More help

Domain of Applicability

A free-text section of the KER description that the developers can use to explain their rationale for the taxonomic, life stage, or sex applicability structured terms. More help
  • Evidence suggests that sox9 and its function in craniofacial development (and thus its repression leading to craniofacial malformations), is an evolutionarily conserved phenomenon. This relationship appears to exist in almost all vertebrates and invertebrates that encode one or more versions of the sox9 gene.

References

List of the literature that was cited for this KER description. More help

Al-Dujaili M, Milne TJ, Cannon RD, Farella M. 2018. Postnatal expression of chondrogenic and osteogenic regulatory factor mrna in the rat condylar cartilage. Arch Oral Biol. 93:126-132.

Bobick BE, Thornhill TM, Kulyk WM. 2007. Fibroblast growth factors 2, 4, and 8 exert both negative and positive effects on limb, frontonasal, and mandibular chondrogenesis via mek-erk activation. J Cell Physiol. 211(1):233-243.

Burns FR, Lanham KA, Xiong KM, Gooding AJ, Peterson RE, Heideman W. 2016. Analysis of the zebrafish sox9b promoter: Identification of elements that recapitulate organ-specific expression of sox9b. Gene. 578(2):281-289.

Burns FR, Peterson RE, Heideman W. 2015. Dioxin disrupts cranial cartilage and dermal bone development in zebrafish larvae. Aquat Toxicol. 164:52-60.

Celá P, Buchtová M, Veselá I, Fu K, Bogardi JP, Song Y, Barlow A, Buxton P, Medalová J, Francis-West P et al. 2016. Bmp signaling regulates the fate of chondro-osteoprogenitor cells in facial mesenchyme in a stage-specific manner. Dev Dyn. 245(9):947-962.

Chen J, Sobue T, Utreja A, Kalajzic Z, Xu M, Kilts T, Young M, Wadhwa S. 2011. Sex differences in chondrocyte maturation in the mandibular condyle from a decreased occlusal loading model. Calcif Tissue Int. 89(2):123-129.

Chen J, Sorensen KP, Gupta T, Kilts T, Young M, Wadhwa S. 2009. Altered functional loading causes differential effects in the subchondral bone and condylar cartilage in the temporomandibular joint from young mice. Osteoarthritis Cartilage. 17(3):354-361.

Cowan CM, Cheng S, Ting K, Soo C, Walder B, Wu B, Kuroda S, Zhang X. 2006. Nell-1 induced bone formation within the distracted intermaxillary suture. Bone. 38(1):48-58.

Dutra EH, O'Brien MH, Chen PJ, Wei M, Yadav S. 2021. Intermittent parathyroid hormone [1-34] augments chondrogenesis of the mandibular condylar cartilage of the temporomandibular joint. Cartilage. 12(4):475-483.

Eames BF, Schneider RA. 2008. The genesis of cartilage size and shape during development and evolution. Development. 135(23):3947-3958.

Garcia GR, Goodale BC, Wiley MW, La Du JK, Hendrix DA, Tanguay RL. 2017. In vivo characterization of an ahr-dependent long noncoding rna required for proper sox9b expression. Mol Pharmacol. 91(6):609-619.

Gordon CT, Attanasio C, Bhatia S, Benko S, Ansari M, Tan TY, Munnich A, Pennacchio LA, Abadie V, Temple IK et al. 2014. Identification of novel craniofacial regulatory domains located far upstream of sox9 and disrupted in pierre robin sequence. Hum Mutat. 35(8):1011-1020.

Hirouchi H, Kitamura K, Yamamoto M, Odaka K, Matsunaga S, Sakiyama K, Abe S. 2018. Developmental characteristics of secondary cartilage in the mandibular condyle and sphenoid bone in mice. Arch Oral Biol. 89:84-92.

Hu D, Colnot C, Marcucio RS. 2008. Effect of bone morphogenetic protein signaling on development of the jaw skeleton. Dev Dyn. 237(12):3727-3737.

Huang L, Li M, Li H, Yang C, Cai X. 2015. Study of differential properties of fibrochondrocytes and hyaline chondrocytes in growing rabbits. Br J Oral Maxillofac Surg. 53(2):187-193.

Huysseune A, Takle H, Soenens M, Taerwe K, Witten PE. 2008. Unique and shared gene expression patterns in atlantic salmon (salmo salar) tooth development. Dev Genes Evol. 218(8):427-437.

Koskinen J, Karlsson J, Olsson PE. 2009. Sox9a regulation of ff1a in zebrafish (danio rerio) suggests an involvement of ff1a in cartilage development. Comp Biochem Physiol A Mol Integr Physiol. 153(1):39-43.

Lefebvre V, Dvir-Ginzberg M. 2017. Sox9 and the many facets of its regulation in the chondrocyte lineage. Connect Tissue Res. 58(1):2-14.

Lekvijittada K, Hosomichi J, Maeda H, Hong H, Changsiripun C, Kuma YI, Oishi S, Suzuki JI, Yoshida KI, Ono T. 2021. Intermittent hypoxia inhibits mandibular cartilage growth with reduced tgf-β and sox9 expressions in neonatal rats. Sci Rep. 11(1):1140.

Lin Q, He Y, Gui J-F, Mei J. 2021. Sox9a, not sox9b is required for normal cartilage development in zebrafish. Aquaculture and Fisheries. 6(3):254-259.

Ng AF, Yang YO, Wong RW, Hägg EU, Rabie AB. 2006. Factors regulating condylar cartilage growth under repeated load application. Front Biosci. 11:949-954.

Nie X. 2006. Sox9 mrna expression in the developing palate and craniofacial muscles and skeletons. Acta Odontol Scand. 64(2):97-103.

Nonaka K, Shum L, Takahashi I, Takahashi K, Ikura T, Dashner R, Nuckolls GH, Slavkin HC. 1999. Convergence of the bmp and egf signaling pathways on smad1 in the regulation of chondrogenesis. Int J Dev Biol. 43(8):795-807.

Rabie AB, Hägg U. 2002. Factors regulating mandibular condylar growth. Am J Orthod Dentofacial Orthop. 122(4):401-409.

Semba I, Nonaka K, Takahashi I, Takahashi K, Dashner R, Shum L, Nuckolls GH, Slavkin HC. 2000. Positionally-dependent chondrogenesis induced by bmp4 is co-regulated by sox9 and msx2. Dev Dyn. 217(4):401-414.

Serrano MJ, So S, Hinton RJ. 2014. Roles of notch signalling in mandibular condylar cartilage. Arch Oral Biol. 59(7):735-740.

Shi G, Cui Q, Pan Y, Sheng N, Sun S, Guo Y, Dai J. 2017. 6:2 chlorinated polyfluorinated ether sulfonate, a pfos alternative, induces embryotoxicity and disrupts cardiac development in zebrafish embryos. Aquat Toxicol. 185:67-75.

Shi X, He C, Zuo Z, Li R, Chen D, Chen R, Wang C. 2012. Pyrene exposure influences the craniofacial cartilage development of sebastiscus marmoratus embryos. Mar Environ Res. 77:30-34.

Shibata S, Suda N, Suzuki S, Fukuoka H, Yamashita Y. 2006. An in situ hybridization study of runx2, osterix, and sox9 at the onset of condylar cartilage formation in fetal mouse mandible. J Anat. 208(2):169-177.

Shimomura T, Kawakami M, Tatsumi K, Tanaka T, Morita-Takemura S, Kirita T, Wanaka A. 2019. The role of the wnt signaling pathway in upper jaw development of chick embryo. Acta Histochem Cytochem. 52(1):19-26.

Terao F, Takahashi I, Mitani H, Haruyama N, Sasano Y, Suzuki O, Takano-Yamamoto T. 2011. Fibroblast growth factor 10 regulates meckel's cartilage formation during early mandibular morphogenesis in rats. Dev Biol. 350(2):337-347.

Tussellino M, Ronca R, Carotenuto R, Pallotta MM, Furia M, Capriglione T. 2016. Chlorpyrifos exposure affects fgf8, sox9, and bmp4 expression required for cranial neural crest morphogenesis and chondrogenesis in xenopus laevis embryos. Environ Mol Mutagen. 57(8):630-640.

Wakamatsu Y, Nomura T, Osumi N, Suzuki K. 2014. Comparative gene expression analyses reveal heterochrony for sox9 expression in the cranial neural crest during marsupial development. Evol Dev. 16(4):197-206.

Wang X, Sun H, Zhu Y, Tang Y, Xue X, Nie P, Zhu M, Wang B. 2019. Bilateral intermittent nasal obstruction in adolescent rats leads to the growth defects of mandibular condyle. Arch Oral Biol. 106:104473.

Wang Y, Liu C, Rohr J, Liu H, He F, Yu J, Sun C, Li L, Gu S, Chen Y. 2011. Tissue interaction is required for glenoid fossa development during temporomandibular joint formation. Dev Dyn. 240(11):2466-2473.

Watanabe M, Kawasaki K, Kawasaki M, Portaveetus T, Oommen S, Blackburn J, Nagai T, Kitamura A, Nishikawa A, Kodama Y et al. 2016. Spatio-temporal expression of sox genes in murine palatogenesis. Gene Expr Patterns. 21(2):111-118.

Wu Y, Zuo Z, Chen M, Zhou Y, Yang Q, Zhuang S, Wang C. 2018. The developmental effects of low-level procymidone towards zebrafish embryos and involved mechanism. Chemosphere. 193:928-935.

Xiong KM, Peterson RE, Heideman W. 2008. Aryl hydrocarbon receptor-mediated down-regulation of sox9b causes jaw malformation in zebrafish embryos. Mol Pharmacol. 74(6):1544-1553.

Yahiro K, Higashihori N, Moriyama K. 2017. Histone methyltransferase setdb1 is indispensable for meckel's cartilage development. Biochem Biophys Res Commun. 482(4):883-888.

Zhang H, Zhao X, Zhang Z, Chen W, Zhang X. 2013a. An immunohistochemistry study of sox9, runx2, and osterix expression in the mandibular cartilages of newborn mouse. Biomed Res Int. 2013:265380.

Zhang X, Dai J, Lu L, Zhang J, Zhang M, Wang Y, Guo M, Wang X, Wang M. 2013b. Experimentally created unilateral anterior crossbite induces a degenerative ossification phenotype in mandibular condyle of growing sprague-dawley rats. J Oral Rehabil. 40(7):500-508.