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bioRxiv · 10.64898/2026.06.08.730829

Chromosomal requirements for formation of multivalent human nucleoli

Giemza, K.·Mangan, H.·McStay, B.
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Abstract

Human nucleoli are multivalent, involving contributions from up to ten NOR-bearing acrocentric chromosome p-arms. Precision mega-base scale chromosome engineering defines the requirements for this major genome organisational event. NOR deletions reveal that p-arm nucleolar association is rDNA independent. Deletion of all NOR-distal or proximal sequences individually have only a marginal effect on nucleolar association. Finally, deletion of an entire p-arm, while leaving centromere function intact, destroys the nucleolar association potential of that acrocentric. We propose that formation of multivalent nucleoli is not a nucleolar fusion event per se; rather it is driven by the surrounding chromosomal context of NORs.

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Giemza, K., Mangan, H., McStay, B.. 2026-06-08. Chromosomal requirements for formation of multivalent human nucleoli. https://doi.org/10.64898/2026.06.08.730829

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