Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2023 Jan 3;13(1):a041303.
doi: 10.1101/cshperspect.a041303.

Retinal Degeneration Animal Models in Bardet-Biedl Syndrome and Related Ciliopathies

Affiliations
Review

Retinal Degeneration Animal Models in Bardet-Biedl Syndrome and Related Ciliopathies

Clarisse Delvallée et al. Cold Spring Harb Perspect Med. .

Abstract

Retinal degeneration due to photoreceptor ciliary-related proteins dysfunction accounts for more than 25% of all inherited retinal dystrophies. The cilium, being an evolutionarily conserved and ubiquitous organelle implied in many cellular functions, can be investigated by way of many models from invertebrate models to nonhuman primates, all these models have massively contributed to the pathogenesis understanding of human ciliopathies. Taking the Bardet-Biedl syndrome (BBS) as an emblematic example as well as other related syndromic ciliopathies, the contribution of a wide range of models has enabled to characterize the role of the BBS proteins in the archetypical cilium but also at the level of the connecting cilium of the photoreceptors. There are more than 24 BBS genes encoding for proteins that form different complexes such as the BBSome and the chaperone proteins complex. But how they lead to retinal degeneration remains a matter of debate with the possible accumulation of proteins in the inner segment and/or accumulation of unwanted proteins in the outer segment that cannot return in the inner segment machinery. Many BBS proteins (but not the chaperonins for instance) can be modeled in primitive organisms such as Paramecium, Chlamydomonas reinardtii, Trypanosoma brucei, and Caenorhabditis elegans These models have enabled clarifying the role of a subset of BBS proteins in the primary cilium as well as their relations with other modules such as the intraflagellar transport (IFT) module, the nephronophthisis (NPHP) module, or the Meckel-Gruber syndrome (MKS)/Joubert syndrome (JBTS) module mostly involved with the transition zone of the primary cilia. Assessing the role of the primary cilia structure of the connecting cilium of the photoreceptor cells has been very much studied by way of zebrafish modeling (Danio rerio) as well as by a plethora of mouse models. More recently, large animal models have been described for three BBS genes and one nonhuman primate model in rhesus macaque for BBS7 In completion to animal models, human cell models can now be used notably thanks to gene editing and the use of induced pluripotent stem cells (iPSCs). All these models are not only important for pathogenesis understanding but also very useful for studying therapeutic avenues, their pros and cons, especially for gene replacement therapy as well as pharmacological triggers.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Schematic representation of a primary cilium. The transversal section at the axoneme level shows the 9 + 0 structure of the microtubule cytoskeleton composed of tubulin A and B. The basal body corresponds to a derived centriole that serves as a platform for the formation of the cilium. The transition zone is a specialized region that regulates the protein entry inside and outside the cilium. Ciliary proteins and signaling receptors are transported between the base and the apex of the cilium by the intraflagellar transport (IFT) proteins that interact with the molecular motors (kinesin and dynein). (Figure adapted from Delvallée 2020, p. 6, with permission from the author.)
Figure 2.
Figure 2.
Abacus of ciliopathies. Representation of the major clinical features depending on the considered ciliopathy. (LCA) Leber's congenital amaurosis, (NPHP) nephronophthisis, (ALMS) Alström syndrome, (MORM) mental retardation, obesity, retinal dystrophy, and micropenis, (BBS) Bardet–Biedl syndrome, (OFD) oro-facial-digital. (Figure adapted from Delvallée 2020, p. 30, with permission from the author.)
Figure 3.
Figure 3.
Incidence of genes related to Bardet–Biedl syndrome (BBS) and localization of corresponding proteins in a generic primary cilium. (A) Diagram representing the proportion of patient carriers of mutation in each BBS gene among the 80% of patients with a solved genetic diagnosis. BBS1 and BBS10 are the two major BBS contributors. (Panel A created from data in Forsyth and Gunay-Aygun 1993; updated July 23, 2020.) (B) Schematic representation showing the location of 22 out of the 24 BBS proteins (identified to date) in various zones of a primary cilium. (Panel B adapted from Delvallée 2020, pp. 16–17, with permission from the author.)

Similar articles

Cited by

References

    1. Airik R, Slaats GG, Guo Z, Weiss AC, Khan N, Ghosh A, Hurd TW, Bekker-Jensen S, Schrøder JM, Elledge SJ, et al. 2014. Renal-retinal ciliopathy gene Sdccag8 regulates DNA damage response signaling. J Am Soc Nephrol 25: 2573–2583. 10.1681/ASN.2013050565 - DOI - PMC - PubMed
    1. Ajzenberg H, Slaats GG, Stokman MF, Arts HH, Logister I, Kroes HY, Renkema KY, van Haelst MM, Terhal PA, van Rooij IA, et al. 2015. Non-invasive sources of cells with primary cilia from pediatric and adult patients. Cilia 4: 8. 10.1186/s13630-015-0017-x - DOI - PMC - PubMed
    1. Aleman TS, O'Neil EC, O'Connor K, Jiang YY, Aleman IA, Bennett J, Morgan JIW, Toussaint BW. 2021. Bardet–Biedl syndrome-7 (BBS7) shows treatment potential and a cone-rod dystrophy phenotype that recapitulates the non-human primate model. Ophthalmic Genet 42: 252–265. 10.1080/13816810.2021.1888132 - DOI - PMC - PubMed
    1. Álvarez-Satta M, Castro-Sánchez S, Valverde D. 2017. Bardet–Biedl syndrome as a chaperonopathy: dissecting the major role of chaperonin-like BBS proteins (BBS6-BBS10-BBS12). Front Mol Biosci 4: 55. 10.3389/fmolb.2017.00055 - DOI - PMC - PubMed
    1. Azari AA, Aleman TS, Cideciyan AV, Schwartz SB, Windsor EAM, Sumaroka A, Cheung AY, Steinberg JD, Roman AJ, Stone EM, et al. 2006. Retinal disease expression in Bardet–Biedl syndrome-1 (BBS1) is a spectrum from maculopathy to retina-wide degeneration. Invest Ophthalmol Vis Sci 47: 5004–5010. 10.1167/iovs.06-0517 - DOI - PubMed

MeSH terms

Substances

LinkOut - more resources