Biallelic Loss of Molecular Chaperone Molecule AIP Results in a Novel Severe Multisystem Disease Defined by Defective Proteostasis

Korbonits, M.; Wang, X.; Barry, S.; Lim, C.; Suleyman, O.; De-Tito, S.; Begum, N.; Vignola, M. L.; Hall, C.; Perna, L.; Chapple, P.; Henson, S.; Morales, V.; Bianchi, K.; Edvardsson, V. O.; Ragnarsson, K. A.; Kristinsdottir, V. E.; Debeer, A.; Sleyp, Y.; Zinchenko, R.; Anderson, G.; Duchen, M.; Singh, K.; Chung, C.-Y.; Yuan, Y.; Patel, S.; Aksoy, E.; Borovikov, A. O.; Bjornsson, H. T.; Van Esch, H.; Czibik, G.; Tooze, S.; Brennan, C. H.; Haworth, O.

doi:10.1101/2024.08.08.604602

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bioRxiv · 10.1101/2024.08.08.604602

Biallelic Loss of Molecular Chaperone Molecule AIP Results in a Novel Severe Multisystem Disease Defined by Defective Proteostasis

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Abstract

Children born with deleterious biallelic variants of the chaperone aryl hydrocarbon receptor interacting protein (AIP) have a novel pediatric metabolic disease presenting a severe, complex clinical phenotype characterized by failure to develop following birth. Analysis of Aip knockout mouse embryonic fibroblasts and patient-derived dermal fibroblasts revealed that AIP was required to support proteostasis; including proteasome activity, induction of autophagy and lysosome function. aip knockout zebrafish, recapitulated the phenotype of the children; dying at an early stage of development when autophagy is required to adapt to periods of starvation. Our results demonstrate that AIP plays a crucial role in initiating autophagy and maintaining proteostasis in vitro and in vivo. One Sentence SummaryHomozygous loss of the chaperone AIP results in a novel pediatric disease exhibiting multiple features of a lysosomal storage disease.

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Korbonits, M., Wang, X., Barry, S., Lim, C., Suleyman, O., De-Tito, S., Begum, N., Vignola, M. L., Hall, C., Perna, L., Chapple, P., Henson, S., Morales, V., Bianchi, K., Edvardsson, V. O., Ragnarsson, K. A., Kristinsdottir, V. E., Debeer, A., Sleyp, Y., Zinchenko, R., Anderson, G., Duchen, M., Singh, K., Chung, C.-Y., Yuan, Y., Patel, S., Aksoy, E., Borovikov, A. O., Bjornsson, H. T., Van Esch, H., Czibik, G., Tooze, S., Brennan, C. H., Haworth, O.. 2024-08-08. Biallelic Loss of Molecular Chaperone Molecule AIP Results in a Novel Severe Multisystem Disease Defined by Defective Proteostasis. https://doi.org/10.1101/2024.08.08.604602

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