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Updated: Oct 11, 2026

SUMO-Binding Entities (SUBEs) as Tools for the Enrichment, Isolation, Identification, and Characterization of the SUMO Proteome in Liver Cancer
Published on: November 1, 2019
Serine base-exchange in rat liver nuclei
A Dygas1, K Przybyłek, A Meljon
1Nencki Institute of Experimental Biology, Department of Molecular and Cellular Neurobiology, 3 Pasteur Street, 02-093, Warsaw, Poland. adygas@nencki.gov.pl
Abstract:
It has been shown that the incorporation of [(14)C]serine into phosphatidylserine (PS) in isolated rat liver nuclei is intrinsic to this organelle as attested by marker enzyme activity. Serine incorporation into PS was the highest in nuclei depleted of the outer membrane of the nuclear envelope (nucleoplasts) and negligible in the outer membrane. Trypsin treatment of nucleoplasts caused a strong inactivation of PS synthesis and only a moderate one of the NAD pyrophosphorylase activity, the marker enzyme of the inner nuclear membrane. We suggest that the serine base-exchange enzyme is located in the inner membrane of the nuclear envelope and accessible from the periplasmic surface of this membrane.
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