This domain is found at the N-terminal of nucleolus and neural progenitor protein (NEPRO) which may play a role in cortex development as part of the Notch signalling pathway. Downstream of Notch may repress the expression of proneural genes and inhibit neuronal differentiation thereby maintaining neural progenitors [1]. NEPRO may also play a role in preimplentation embryo development [2]. NEPRO interacts with multiple protein subunits of RMRP and is implicated in Anauxetic dysplasia 3 [3]. NEPRO is likely the human orthologue of RMP1 subunit from yeast and they share a four-helix bundle domain structure.

1: Identification of Nepro, a gene required for the maintenance of neocortex neural progenitor cells downstream of Notch. Muroyama Y, Saito T; Development. 2009;136:3889-3893. PMID:19906856

2: Nepro is localized in the nucleolus and essential for preimplantation development in mice. Hashimoto M, Sato T, Muroyama Y, Fujimura L, Hatano M, Saito T; Dev Growth Differ. 2015;57:529-538. PMID:26178919

3: An emerging ribosomopathy affecting the skeleton due to biallelic variations in NEPRO. Narayanan DL, Shukla A, Kausthubham N, Bhavani GS, Shah H, Mortier G, Girisha KM; Am J Med Genet A. 2019;179:1709-1717. PMID:31250547